Kinetic Isotope Effects
|
|
- Maurice Harrison
- 5 years ago
- Views:
Transcription
1 1 Experiment 31 Kinetic Isotope Effects Isotopic substitution is a useful technique for the probing of reaction mechanisms. The change of an isotope may affect the reaction rate in a number of ways, providing clues to the pathway of the reaction. The advantage of isotopic substitution is that this is the least disturbing structural change that can be effected in a molecule. Typically, the isotopic substitution is made with an atom that takes part in the reaction. This will produce a primary isotope effect. If the substitution is made with an atom that does not directly participate in the reaction, a secondary isotope effect exists. Each effect can give different mechanistic information. 1 Primary and secondary alkyl halides undergo elimination reactions under basic conditions. It is generally considered that an E2 mechanism is involved, in which the breakage of the C H bond to the halide group and the departure of the halide leaving group occur simultaneously in the bimolecular transition state. For example; If the protium is replaced by the heavier isotope deuterium, a slower rate of elimination will be observed because the C D bond has lower zero-point energy than the C H bond and a higher activation energy for bond cleavage is therefore required. The change in reaction rate that occurs upon isotope substitution is known as kinetic isotope effect.
2 2 Chem 463 Organic The elimination reactions of 2-phenethyl bromide and 2-phenethyl-2,2-d 2 bromide under identical conditions of attacking base, temperature and solvent will be examined. A large excess of the base sodium ethoxide will be used so that the reaction will be pseudo first order with respect to the bromide. The kinetics of the reactions will be followed by recording the increase in the UV absorbance of the styrene produced. The rate of production of styrene is given by: dx / kc ( 0 x)[naoet] k( c0 x) dt 1 where x is the concentration of styrene at time = t, k is the second order rate constant, c 0 is the initial concentration of the bromide. When the concentration of the base is significantly greater than the initial concentration of the bromide, there is little change in the concentration of the base as the reaction progresses, and the reaction may be considered as a pseudo first order reaction, with a pseudo first order rate constant k /. The pseudo first order rate constant is related to the second order rate constant by: k / = k[naoet]. Integration and manipulation of equation 1 provides us with equation 2: ln(a A ) kt inf t / 2 which is the standard equation for a pseudo first order reaction. The manipulation recognizes that absorbance is directly related to concentration (Beer s Law), and A t and A inf are the absorbances at time = t and infinite time, respectively. We are now able to determine k / from the absorbance of the styrene produced. If we determine both k / H and k/ D, the isotope effect k/ H /k/ D may now be calculated. The protonated bromide was purchased commercially. The deuterated bromide was prepared via the following route, modified from the method described in reference 2(a).
3 3 The isotope effect is not limited to the compound under study. Isotopic substitution in the solvent used in the reaction will also give rise to a solvent effect, if the solvent is involved in the reaction. Measurements of these isotope effects can give information about mechanisms such as hydrolysis. The uncatalyzed hydrolysis of acetic anhydride in water is a reaction that may be studied by the kinetic solvent isotope effect. The equation, in protonated water is: A kinetic solvent isotope effect will be observed if any of the following change on going from reactant to transition states: a difference in bulk solvent properties, a difference in solute/solvent interactions, a difference in the zero-point energy of the O H (O D) bond in the reacting solvent, or a difference in the zero-point energy of solute bonds that have exchanged with the solvent. A primary kinetic solvent isotope effect will be observed if a proton (deuteron) is transferred from the solvent in the rate-determining step of a reaction. This is the case here. The proposed transition state for the hydrolysis of acetic anhydride is shown at right. The rate-determining step of the mechanism is the initial attack of water on a carbonyl group of the anhydride. This step is an example of general base assisted nucleophilic attack. The first water molecule acts as a nucleophile, attacking the carbon of the carbonyl group. The second molecule of water acts as a general base, assisting in the removal of a proton from the nucleophilic molecule. In this structure, H a provides a primary kinetic isotope effect, and H b contributes a secondary effect. H c does not contribute an isotope effect. The kinetics of this reaction in D 2 O and H 2 O will be measured by by UV spectroscopy. There is a large excess of water in the reaction, and the pseudo first order rate equation can be used to determine the rate constant of the reaction. These reactions are relatively fast, and the kinetics software package on the Cary UV instrument will be used to record the changing absorbances of acetic anhydride at 228 nm.
4 4 Chem 463 Organic What to Do? Experimental To complete the basic experiment, the two bromides are obtained as unknowns, and their kinetics are studied. To complete the full report, the deuterated bromide is synthesized from the alcohol, the E2 reaction is studied, and the solvent isotope effect is also studied. Preparation of the Mesylate To a solution of the deuterated 2-phenylethanol (500 mg), triethylamine (500 mg) and N,N-4-dimethylaminopyridine (40 mg) in dichloromethane (10 ml), slowly add methanesulfonyl chloride (1.0 g) with stirring. After the addition is complete, continue the stirring for 1 hour. When the reaction is complete, dilute the reaction mixture with dichloromethane (25 ml), and wash the organic solution with 10% hydrochloric acid (2 x 25 ml), and water (25 ml). Dry (MgSO 4 ), filter and concentrate the organic solution to yield the mesylate. Record the yield, IR and 1 H NMR spectrum of the product. Preparation of the Bromide Prepare a mixture of the mesylate, lithium bromide (2 eq), and acetone (4 ml/mmol mesylate). Reflux the mixture for 4 hours (or longer), and allow it to stand overnight at room temperature. Remove the acetone on the rotary evaporator, and add water (25 ml) to the residue. Extract the aqueous solution with ether (3 x 20 ml). Dry (MgSO 4 ), filter and concentrate the organic solution to yield the crude bromide. Purify the bromide by bulb-to-bulb distillation under aspirator vacuum. Record the yield of the deuterated bromide. For both bromides record the IR, 1 H and 13 C NMR, and submit a small amount of the bromide for analysis by mass spectrometry (we may use the gc-ms). Estimate the % deuteration in the product. Bromides as Unknowns Record the IR, 1 H and 13 C NMR spectra, and obtain the mass spectra of the two bromides provided as unknowns. It is not necessary to positively identify the two compounds before beginning the kinetic study. Kinetics of the E2 Reaction Prepare 250 ml of 10-2 M sodium ethoxide solution by carefully dissolving small pieces of sodium in ethanol. Take care to minimize the exposure of this solution to the atmosphere! Place the stoppered solution in a constant temperature bath at 60 o C and allow to equilibrate. Prepare 10 ml of a solution of 2-phenethyl bromide in ethanol by transferring 12 L (equivalent to 16.2 mg) of the bromide to a volumetric flask, and making up to the mark with ethanol. Transfer 1 ml of this solution to a 100 ml volumetric flask, stopper and allow to equilibrate in the 60 o C constant temperature bath. Repeat for the other bromide, as the kinetics are studied simultaneously. Add the sodium ethoxide solution to the 100 ml volumetric flask containing the bromide and make up to the mark with the ethoxide solution. Thoroughly mix the solution and return it to the constant temperature bath. Note the time of addition (t = 0). At time intervals of 15 minutes remove a small amount of the reaction mixture and record its absorbance (A) at 240 nm against the 10-2 M sodium ethoxide solution as a reference. Record the reference once only at the start of the experiment. The styrene produced in the elimination reaction absorbs strongly at this wavelength
5 5 whereas the absorbance due to 2-phenethyl bromide is only minimal. Continue to monitor the reaction for 2 3 hours. Keep the reaction mixture in the constant temperature bath and record the absorbance readings after 48 and 96 hours to obtain A inf. Calculate the pseudo first order rate constant k / H (or k/ D ). Solvent Isotope Effect For each kinetic run, pipette 3.0 ml of the supplied potassium chloride solutions (0.02 M in H 2 O or D 2 O, equivalent to 16.9 mg in 10 ml) into a quartz cuvette. To start the reaction, inject 20 L of the standard acetic anhydride solution (2.0 M in acetonitrile, equivalent to 208 mg in 2.0 ml) into the cuvette, gently (and quickly) shake the cuvette to mix the reagents. Place the cuvette into the sample beam of the Cary UV instrument, and record the decay of the absorbance of acetic anhydride at 228 nm. Use the kinetics software on the Cary to compute the rate constant. Record the absorbance for either 30 minutes (H 2 O), or 120 minutes (D 2 O). Repeat the kinetic run for each isotope, and average the rate constants. Report Analyze all spectra recorded, and discuss the differences between protonated and deuterated compounds. Calculate the isotope effect k / H /k/ D for both the E2 reaction and the acetic anhydride hydrolysis. Comment on the results of the experiment, on any assumptions made in the kinetic study, and relate the results to the mechanism of the reaction. References 1. Lowry, T.H.; Richardson, K.S. Mechanism and Theory in Organic Chemistry, 3 nd Ed., Harper and Row, 1987 pp Carey, F.A.; Sundberg, R.J. Advanced Organic Chemistry Part A, 2 nd Ed., Plenum Press, pp (a) Saunders, W.H.; Edison, D.H. J. Am. Chem. Soc. 1960, 82, (b) Saunders, W.H.; Williams, R.A. J. Am. Chem. Soc. 1957, 79, (c) Saunders, W.H.; Bushman, D.G.; Cockerill, A.F J. Am. Chem. Soc. 1968, 90, The kinetic solvent isotope experiment is adapted from El Seoud, O.A.; Bazito, R.C.; Sumodjo, P.T J. Chem. Ed. 1997, 74,
Sodium Borohydride Reduction of Benzoin
Sodium Borohydride Reduction of Benzoin Introduction The most common and useful reducing agents for reducing aldehydes, ketones, and other functional groups are metal hydride reagents. The two most common
More informationExperiment 3. Condensation Reactions of Ketones and Aldehydes: The Aldol Condensation Reaction.
Experiment 3. Condensation Reactions of Ketones and Aldehydes: The Aldol Condensation Reaction. References: Brown & Foote, Chapters 16, 19, 23 INTRODUCTION: This experiment continues the saga of carbon-carbon
More informationExperiment : Reduction of Ethyl Acetoacetate
Experiment 7-2007: eduction of Ethyl Acetoacetate EXPEIMENT 7: eduction of Carbonyl Compounds: Achiral and Chiral eduction elevant sections in the text: Fox & Whitesell, 3 rd Ed. Chapter 12, pg.572-584.
More informationChemistry 283g Experiment 4
Chemistry 283g xperiment 4 XPRIMNT 4: lectrophilic Aromatic Substitution: A Friedel-Craft Acylation Reaction Relevant sections in the text: Fox & Whitesell, 3 rd d. Chapter 11, especially pg. 524-526,
More informationMultistep Synthesis of 5-isopropyl-1,3-cyclohexanedione
Multistep Synthesis of 5-isopropyl-1,3-cyclohexanedione The purpose of this experiment was to synthesize 5-isopropyl-1,3-cyclohexanedione from commercially available compounds. To do this, acetone and
More information2017 Reaction of cinnamic acid chloride with ammonia to cinnamic acid amide
217 Reaction of cinnamic acid chloride with ammonia to cinnamic acid amide O O Cl NH 3 NH 2 C 9 H 7 ClO (166.6) (17.) C 9 H 9 NO (147.2) Classification Reaction types and substance classes reaction of
More information12AL Experiment 11 (3 days): Nucleophilic Substitution Reactions
12AL Experiment 11 (3 days): Nucleophilic Substitution Reactions Instructor note: Day 1 (half of the class); Day 2 (other half); Day 3 (everyone to finish up any separation & purification steps etc). Initial
More informationTOSYLHYDRAZONE CLEAVAGE OF AN α,β-epoxy KETONE; OXIDATIVE KMnO 4 CLEAVAGE OF AN ALKYNE EXPERIMENT A
1 EXPERIMENT A EPOXIDATION OF AN α,β-unsaturated KETONE; TOSYLYDRAZONE CLEAVAGE OF AN α,β-epoxy KETONE; OXIDATIVE KMnO 4 CLEAVAGE OF AN ALKYNE The goal of this experiment is the correct assignment of the
More information4023 Synthesis of cyclopentanone-2-carboxylic acid ethyl ester from adipic acid diethyl ester
NP 4023 Synthesis of cyclopentanone-2-carboxylic acid ethyl ester from adipic acid diethyl ester NaEt C 10 H 18 4 Na C 2 H 6 C 8 H 12 3 (202.2) (23.0) (46.1) (156.2) Classification Reaction types and substance
More informationCHEM 344 Fall 2015 Final Exam (100 pts)
CHEM 344 Fall 2015 Final Exam (100 pts) Name: TA Name: DO NOT REMOVE ANY PAGES FROM THIS EXAM PACKET. Have a swell winter break. Directions for drawing molecules, reactions, and electron-pushing mechanisms:
More informationGRIGNARD REACTION Synthesis of Benzoic Acid
1 GRIGNARD REACTION Synthesis of Benzoic Acid In the 1920 s, the first survey of the acceleration of chemical transformations by ultrasound was published. Since then, many more applications of ultrasound
More informationORG1 Syntheses of Acetaminophen and Aspirin
RG1 Syntheses of Acetaminophen and Aspirin Estimated Time Required: 60 minutes Introduction Ethanoylation (better known as acetylation) is the introduction of an acetyl functional group onto a suitable
More informationSupporting Information. for. Angew. Chem. Int. Ed. Z Wiley-VCH 2003
Supporting Information for Angew. Chem. Int. Ed. Z53001 Wiley-VCH 2003 69451 Weinheim, Germany 1 Ordered Self-Assembly and Electronic Behavior of C 60 -Anthrylphenylacetylene Hybrid ** Seok Ho Kang 1,
More informationSYNTHESIS OF 1-BROMOBUTANE Experimental procedure at macroscale (adapted from Williamson, Minard & Masters 1 )
SYNTHESIS OF 1-BROMOBUTANE Experimental procedure at macroscale (adapted from Williamson, Minard & Masters 1 ) Introduction 1-bromobutane is a primary alkyl halide (primary alkyl) and therefore it is produced
More informationR R CH. Some reactions of alcohols vary depending on their classification as 1º, 2º, or 3º alcohols.
Experiment: Alcohol Reactions Alcohols are important organic molecules characterized by an alkyl group covalently bonded to a hydroxyl group. They may be classified as primary, secondary, or tertiary,
More informationTerpenoids: Investigations in Santonin Chemistry
1 Experiment 8 Terpenoids: Investigations in Santonin Chemistry Santonin, (I) is a well-known sesquiterpenoid that has received much study in the past. Because it is a highly functionalized compound, and
More informationSupporting Information for
Electronic Supplementary Material (ESI) for New Journal of Chemistry. This journal is The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017 Supporting Information for
More informationExperiment 12: Grignard Synthesis of Triphenylmethanol
1 Experiment 12: Grignard Synthesis of Triphenylmethanol Reactions that form carbon-carbon bonds are among the most useful to the synthetic organic chemist. In 1912, Victor Grignard received the Nobel
More informationExperiment 1: Preparation of Vanillyl Alcohol
Experiment 1: Preparation of Vanillyl Alcohol INTRDUCTIN A common method for preparing alcohols is the reduction of aldehydes to form primary alcohols [equation (1)] or of ketones to produce secondary
More informationREACTIONS: Reduction of a ketone, acetylation of an alcohol, and a kinetic resolution using a lipase.
CHEM 51LD EXP #2 FALL 2013 SYNTHESIS F ENANTIPURE ALCHLS AND ESTERS USING A LIPASE-BASED KINETIC RESLUTIN REACTINS: Reduction of a ketone, acetylation of an alcohol, and a kinetic resolution using a lipase.
More informationWorking with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training
More informationThe Synthesis of Triphenylmethano. will synthesize Triphenylmethanol, a white crystalline aromatic
HEM 333L rganic hemistry Laboratory Revision 2.0 The Synthesis of Triphenylmethano ol In this laboratory exercise we will synthesize Triphenylmethanol, a white crystalline aromatic compound. Triphenylmethanol
More informationTriazabicyclodecene: an Effective Isotope. Exchange Catalyst in CDCl 3
Triazabicyclodecene: an Effective Isotope Exchange Catalyst in CDCl 3 Supporting Information Cyrille Sabot, Kanduluru Ananda Kumar, Cyril Antheaume, Charles Mioskowski*, Laboratoire de Synthèse Bio-rganique,
More informationReview Experiments Formation of Polymers Reduction of Vanillin
Review Experiments Formation of Polymers What is a polymer? What is polymerization? What is the difference between an addition polymerization and a condensation polymerization? Which type of polymerization
More informationElectronic supporting information for
Electronic Supplementary Material (ESI) for Organic & Biomolecular Chemistry. This journal is The Royal Society of Chemistry 2016 Electronic supporting information for The effects of an ionic liquid on
More informationExperiment 2 Solvent-free Aldol Condensation between 3,4-dimethoxybenzaldehyde and 1-indanone
Experiment 2 Solvent-free Aldol Condensation between 3,4-dimethoxybenzaldehyde and 1-indanone Chemical Concepts Carbonyl chemistry, base catalyzed aldol reaction, melting point, recrystallization Green
More informationMolecular Imaging of Labile Iron(II) Pools in Living Cells with a Turn-on Fluorescent Probe
Supporting Information for Molecular Imaging of Labile Iron(II) Pools in Living Cells with a Turn-on Fluorescent Probe Ho Yu Au-Yeung, Jefferson Chan, Teera Chantarojsiri and Christopher J. Chang* Departments
More informationAs you can see from the reactions below for the reduction of camphor, there are two possible products, borneol and isoborneol.
E19-1 Experiment 19 Fig. 19-1 REDUTIN WIT NaB 4 : STERI AND NJUGATIN EFFETS (3 Experiments) erbert. Brown (1912-2004) Received Nobel prize for synthetic organic chemistry work with boron compounds. http://nobelprize.org/chemistry/laureates/1979/brown-autobio.html
More informationSupporting Information
Supporting Information Incorporation of a Sugar Unit into a C C N Pincer Pd Complex Using Click Chemistry and Its Dynamic Behavior in Solution and Catalytic Ability toward the Suzuki Miyaura Coupling in
More informationPERIODIC RELATIONSHIPS
PERIODIC RELATIONSHIPS OBJECTIVES: Gaining insight into property and reactivity trends within families and across periods for the chemical elements through experimental observation. SKILLS: Observations,
More informationAn Efficient Total Synthesis and Absolute Configuration. Determination of Varitriol
An Efficient Total Synthesis and Absolute Configuration Determination of Varitriol Ryan T. Clemens and Michael P. Jennings * Department of Chemistry, University of Alabama, 500 Campus Dr. Tuscaloosa, AL
More informationSupplementary Material (ESI) for Chemical Communication
Supplementary Material (ESI) for Chemical Communication Syntheses and Characterization of Polymer-Supported Organotrifluoroborates: Applications in Radioiodination Reactions Li Yong; Min-Liang Yao; James
More informationNucleophilic Addition to Carbonyl: Grignard Reaction with a Ketone
Experiment 7 Nucleophilic Addition to Carbonyl: Grignard eaction with a Ketone prepared by Jan William Simek, California Polytechnic State University modified by Hyunwoo Kim, Sunkyu Han and Eunyoung Yoon,
More informationWorking with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training
More informationChemistry 254 Lab Experiment 1: Qualitative Organic Analysis Summer 2004
Chemistry 254 Lab Experiment 1: Qualitative Organic Analysis Summer 2004 Introduction: Qualitative organic analysis, the identification and characterization of unknown compounds, in an important part of
More information3. Two unknown samples are found to have the same R f value under identical TLC conditions. Are they the same compound? Explain.
I. Techniques in Organic Lab and TLC Analysis a. Thin-Layer Chromatography 2. A TLC plate displays the compound spot approximately 3.2 cm above the base line upon visualization; the solvent ran 4.1 cm
More informationComplex Promoted by Electron-Deficient Alkenes. Brian V. Popp and Shannon S. Stahl*
Oxidatively-Induced Reductive Elimination of Dioxygen from an η 2 -Peroxopalladium(II) Complex Promoted by Electron-Deficient Alkenes Brian V. Popp and Shannon S. Stahl* Department of Chemistry, University
More informationReactive fluorescent dye functionalized cotton fabric as a Magic Cloth for selective sensing and reversible separation of Cd 2+ in water
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry C. This journal is The Royal Society of Chemistry 2015 Supplementary Information Reactive fluorescent dye functionalized cotton
More informationPAPER No. : 5; Organic Chemistry-II MODULE No. : 13; Mixed S N 1 and S N 2 Reactions
Subject Chemistry Paper No and Title Module No and Title Module Tag 5; Organic Chemistry-II 13; Mixed S N 1 and S N 2 Reactions CHE_P5_M13 TABLE OF CONTENTS 1. Learning Outcomes 2. Introduction 3. Nature
More informationExperiment 7 - Preparation of 1,4-diphenyl-1,3-butadiene
Experiment 7 - Preparation of 1,4-diphenyl-1,3-butadiene OBJECTIVE To provide experience with the Wittig Reaction, one of the most versatile reactions available for the synthesis of an alkene. INTRODUCTION
More informationChem 2115 Experiment # 6 PERIODIC RELATIONSHIPS
Chem 2115 Experiment # 6 PERIODIC RELATIONSHIPS OBJECTIVES: Gaining insight into property and reactivity trends within families and across periods for the chemical elements through experimental observation.
More informationHonors Cup Synthetic Proposal
onors Cup Synthetic Proposal Section: 270-V Group Members: Azhar Carim, Ian Cross, Albert Tang Title: Synthesis of indigo from -(2-bromoethyl)-2-nitrobenzamide Introduction: Indigo has been used as a dye
More informationTetrahydrofuran (THF) was distilled from benzophenone ketyl radical under an argon
SUPPLEMENTARY METHODS Solvents, reagents and synthetic procedures All reactions were carried out under an argon atmosphere unless otherwise specified. Tetrahydrofuran (THF) was distilled from benzophenone
More informationExperiment DE: Part II Fisher Esterification and Identification of an Unknown Alcohol
Experiment DE: Part II Fisher Esterification and Identification of an Unknown Alcohol Fisher Esterification of an Alcohol (Fraction A) On the Chem 113A website, under "Techniques" and "Videos" review the
More informationSupporting Information For:
Supporting Information For: Peptidic α-ketocarboxylic Acids and Sulfonamides as Inhibitors of Protein Tyrosine Phosphatases Yen Ting Chen, Jian Xie, and Christopher T. Seto* Department of Chemistry, Brown
More informationREACTIONS: Reduction of a ketone, acetylation of an alcohol, and a kinetic resolution using a lipase.
CHEM 51LD EXPERIMENT 2 SYNTHESIS F ENANTIPURE ALCHLS AND ESTERS USING A LIPASE-BASED KINETIC RESLUTIN REACTINS: Reduction of a ketone, acetylation of an alcohol, and a kinetic resolution using a lipase.
More informationExpt 9: The Aldol Condensation
Expt 9: The Aldol Condensation INTRDUCTIN Reactions that form carbon-carbon bonds are particularly important in organic chemistry as they allow the synthesis of more complex structures from simpler molecules.
More informationA supramolecular approach for fabrication of photo- responsive block-controllable supramolecular polymers
Electronic Supplementary Material (ESI) for Polymer Chemistry. This journal is The Royal Society of Chemistry 2014 Supporting Information A supramolecular approach for fabrication of photo- responsive
More informationChemistry 283g- Experiment 3
EXPERIMENT 3: xidation of Alcohols: Solid-Supported xidation and Qualitative Tests Relevant sections in the text: Fox & Whitesell, 3 rd Ed. pg. 448-452. A portion of this experiment is based on a paper
More information(1) You are allowed 10 minutes to read this paper, and 3 hours to complete the questions.
FINAL PAPER PART A 1994 AUSTRALIAN CEMISTRY LYMPIAD Please note that this answer book will be photocopied when returned and then split so that answers are sent to the appropriate markers. For this reason
More informationSUPPLEMENTARY INFORMATION
Synthetic chemistry ML5 and ML4 were identified as K P.(TREK-) activators using a combination of fluorescence-based thallium flux and automated patch-clamp assays. ML5, ML4, and ML5a were synthesized using
More informationFree Radical Chlorination
Free Radical Chlorination Although saturated hydrocarbons are inert to most acidic and basic reagents, they can be halogenated in the presence of a free radical initiator. The process is a chain reaction,
More information12BL Experiment 7: Vanillin Reduction
12BL Experiment 7: Vanillin Reduction Safety: Proper lab goggles/glasses must be worn (even over prescription glasses). WEAR GLOVES and please handle the following chemicals with care: Hydrochloric acid
More informationChemical Kinetics. Reaction rate and activation energy of the acid hydrolysis of ethyl acetate LEC 05. What you need: What you can learn about
LEC 05 Chemical Kinetics Reaction rate and activation energy of the acid hydrolysis What you can learn about Reaction rate Rate law for first and second order reactions Reactions with pseudo-order Arrhenius
More informationStereoselective Synthesis of a Topologically Chiral Molecule: The Trefoil Knot
Stereoselective Synthesis of a Topologically Chiral Molecule: The Trefoil Knot Laure-Emmanuelle Perret-Aebi, Alexander von Zelewsky 1, Christiane Dietrich- Buchecker and Jean-Pierre Sauvage Bis-5,6-pinene
More informationSupporting Information
Supporting Information Wiley-VCH 2012 69451 Weinheim, Germany Concise Syntheses of Insect Pheromones Using Z-Selective Cross Metathesis** Myles B. Herbert, Vanessa M. Marx, Richard L. Pederson, and Robert
More informationSUPPLEMENTARY INFORMATION
SUPPLEMENTARY INFORMATION Supporting Information Kinetic Resolution of Constitutional Isomers Controlled by Selective Protection inside a Supramolecular Nanocapsule Simin Liu, Haiying Gan, Andrew T. Hermann,
More informationTo understand concept of limiting reagents. To learn how to do a vacuum filtration. To understand the concept of recrystallization.
E x p e r i m e n t Synthesis of Aspirin Experiment : http://genchemlab.wordpress.com/-aspirin/ objectives To synthesize aspirin. To understand concept of limiting reagents. To determine percent yield.
More informationExperiment 24. Chemical recycling of poly(ethylene) terephthalate (PET)
Methods of pollution control and waste management Experiment 24 Chemical recycling of poly(ethylene) terephthalate (PET) Manual Department of Chemical Technology The aim of this experiment is to gain knowledge
More informationExperiment 7: Synthesis of an Alkyne from an Alkene
Experiment 7: Synthesis of an Alkyne from an Alkene Part A: Synthesis of meso-stilbene dibromide Part B: Synthesis of diphenylacetylene Reading: Carey & Guiliano Ch. 9 pgs 368-372 Note: This is exp #8
More informationElectronic Supplementary Information
Electronic Supplementary Material (ESI) for Journal of Materials Chemistry A. This journal is The Royal Society of Chemistry 2014 Electronic Supplementary Information Micro- and mesoporous poly(schiff-base)s
More informationRule 2. Rule 1. Rule 4. Rule 3. Rule 5. Rule 6. Rule 7. Rule 8
Rule 1 Follow the directions in your course reader, of your teaching assistant and of your instructor. They are usually much more experienced doing chemistry. Rule 3 When in doubt, ask. This will make
More information12AL Experiment 9: Markovnikov s Rule
12AL Experiment 9: Markovnikov s Rule Safety: Proper lab goggles/glasses must be worn (even over prescription glasses). WEAR GLOVES this lab utilizes hydrogen peroxide which can burn your skin and multiple
More informationAspirin Synthesis H 3 PO 4
Aspirin Synthesis Experiment 10 Aspirin is the common name for the compound acetylsalicylic acid, widely used as a fever reducer and as a pain killer. Salicylic acid, whose name comes from Salix, the willow
More informationSupporting Information
Supporting Information Efficient Temperature Sensing Platform Based on Fluorescent Block Copolymer Functionalized Graphene Oxide Hyunseung Yang, Kwanyeol Paek, and Bumjoon J. Kim * : These authors contributed
More informationSupporting Information
Supporting Information for Macromol. Chem. Phys, DOI: 10.1002/macp.201700302 Phase Segregation in Supramolecular Polymers Based on Telechelics Synthesized via Multicomponent Reactions Ansgar Sehlinger,
More informationCHEMISTRY Organic Chemistry Laboratory II Spring 2019 Lab #2: Grignard Reaction: Preparation of Triphenylmethanol
CHEMISTRY 244 - Organic Chemistry Laboratory II Spring 2019 Lab #2: Grignard Reaction: Preparation of Triphenylmethanol Purpose. In this lab you will use the Grignard Reaction, a classic reaction in organic
More informationNitrogen, ammonia, colorimetry, salicylate-hypochlorite, automated-segmented flow
1. Application Nitrogen, ammonia, colorimetry, salicylate-hypochlorite, automated-segmented flow Parameters and Codes: Nitrogen, ammonia, dissolved, I-2522-90 (mg/l as N): 00608 Nitrogen, ammonia, total-in-bottom-material,
More informationSUPPLEMENTARY INFORMATION
DOI: 10.1038/NCHEM.2303 Light-controlled self-assembly of non-photoresponsive nanoparticles Pintu K. Kundu, 1 Dipak Samanta, 1 Ron Leizrowice, 1,2 Baruch Margulis, 1,3 Hui Zhao, 1 Martin Börner, 1,4 T.
More informationExperiment 8: Chlorination of 1-Chlorobutane
1 Experiment 8: Chlorination of 1-Chlorobutane Alkanes contain only nonpolar carbon-hydrogen and carbon-carbon single bonds, which makes them unreactive toward most acidic and basic reagents. They can,
More informationChia-Shing Wu, Huai-An Lu, Chiao-Pei Chen, Tzung-Fang Guo and Yun Chen*
Electronic Supplementary Material (ESI) for rganic & Biomolecular Chemistry Supporting Information Water/alcohol soluble electron injection material containing azacrown ether groups: Synthesis, characterization
More informationAcid Anhydrides CH3 C. ethanoic anhydride.
arboxylic acid derivatives: Acyl hlorides and Acid Anhydrides Acyl hlorides l ethanoyl chloride Acyl chlorides are much more reactive than carboxylic acids Acid Anhydrides ethanoic anhydride. Acid anhydrides
More informationElectronic Supplementary Information (12 pages)
Electronic Supplementary Material (ESI) for ChemComm. This journal is The Royal Society of Chemistry 2014 A C 2 -responsive pillar[5]arene: synthesis and self-assembly in water Kecheng Jie, Yong Yao, Xiaodong
More informationEthers. Synthesis of Ethers. Chemical Properties of Ethers
Page 1 of 6 like alcohols are organic derivatives of water, but lack the labile -OH group. As a result, ethers, except for epoxides, are usually not very reactive and are often used as solvents for organic
More informationNucleophilic displacement - Formation of an ether by an S N 2 reaction The Williamson- Ether Synthesis
Nucleophilic displacement - Formation of an ether by an S N 2 reaction The Williamson- Ether Synthesis Bond formation by use of an S N 2 reaction is very important for organic and biological synthesis.
More informationmedia), except those of aluminum and calcium
1- Aspirin occurs as white crystals or as a white crystalline powder. 2- It is slightly soluble in water (1:300), soluble in alcohol (1 :5), chloroform (1:17) & ether (1:15). It dissolves easily in glycerin.
More informationSynthesis of Tetraphenylcyclopentadienone. Becky Ortiz
Synthesis of Tetraphenylcyclopentadienone Becky Ortiz Introduction An aldol reaction is a reaction in which aldehydes or ketones undergo a base- catalyzed carbonyl condensation reaction to form a beta-
More informationHonors Cup Synthetic Proposal
onors up Synthetic Proposal Section: 221 Group Members: Shahid Ali, Jamuna Kesavan, harles Weidle, Pooja Desai, Suellen Yin Title: Synthesis of Vanillin: Mmmm What s that Aroma? Introduction: Vanillin
More informationScheme 2: Formation of Di- Halide via Chloronium Intermediate
Bromination of Alkenes CHM226 Background The carbon- carbon double bond, also known as an alkene, is a very important functional group in organic chemistry, and is often used as a precursor in the synthesis
More informationEXPERIMENT 3 THE IODINE CLOCK
EXPERIMENT 3 THE IODINE CLOCK Introduction The Rates of Chemical Reactions Broadly defined, chemical kinetics is the study of the rates at which chemical reactions proceed. Oftentimes, reaction rate data
More informationThe Fragrance of Rum, Isobutyl Propionate
The Fragrance of Rum, Isobutyl Propionate Exp t 82 from K. L. Williamson, Macroscale and Microscale rganic Experiments, 2nd Ed. 1994, Houghton Mifflin, Boston p385; revised Prelab Exercise 6/27/06 Give
More informationOrganic Reactions Susbstitution S N. Dr. Sapna Gupta
Organic Reactions Susbstitution S N 2 Dr. Sapna Gupta Kinetics of Nucleophilic Reaction Rate law is order of reaction 0 order is when rate of reaction is unaffected by change in concentration of the reactants
More informationCHEMISTRY Organic Chemistry Laboratory II Spring 2019 Lab #1: Oxidation of Alcohols to Ketones - Borneol Oxidation (2 weeks)
CHEMISTRY 244 - Organic Chemistry Laboratory II Spring 2019 Lab #1: Oxidation of Alcohols to Ketones - Borneol Oxidation (2 weeks) Purpose. In this lab you will learn about oxidation reactions in organic
More informationIodination of Salicylamide
Iodination of Salicylamide lectrophilic Aromatic Substitution Aromatic compounds are unusually stable because of the delocalization of their electrons. Given that the cloud is so stable, aromatic compounds
More informationThe Friedel-Crafts Reaction: 2-(4-methylbenzoyl)benzoic acid
The Friedel-Crafts Reaction: 2-(4-methylbenzoyl)benzoic acid Exp t 63 from K. L. Williamson, Macroscale and Microscale rganic Experiments, 2nd Ed. 1994, Houghton Mifflin, Boston. p449 revised 10/13/98
More informationParallel sheet structure in cyclopropane γ-peptides stabilized by C-H O hydrogen bonds
Parallel sheet structure in cyclopropane γ-peptides stabilized by C- hydrogen bonds M. Khurram N. Qureshi and Martin D. Smith* Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge
More informationSupporting Information
Supporting Information Syntheses and characterizations: Compound 1 was synthesized according to Scheme S-1. Scheme S-1 2 N N 5 i N 4 P Et Et iii N 6 ii P Et Et iv v, vi N N i) Fmoc-Su, DIPEA, Acetone;
More informationWorking with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training
More informationEffect of Conjugation and Aromaticity of 3,6 Di-substituted Carbazole On Triplet Energy
Electronic Supplementary Material (ESI) for RSC Advances. This journal is The Royal Society of Chemistry 2018 Electronic Supporting Information (ESI) for Effect of Conjugation and Aromaticity of 3,6 Di-substituted
More informationReductive Amination Reaction
Boston University OpenBU Chemistry http://open.bu.edu Organic Chemistry Laboratory Experiments 2011-07-14 eductive Amination eaction Mulcahy, Seann P. https://hdl.handle.net/2144/1419 Boston University
More informationApplicability of GPC, GC-MS and 13 C NMR techniques and DFRC method in comparative structural studies of Lignin
International Journal of Lignocellulosic Products 2014, 1 (1): 58-71 http://ijlp.gau.ac.ir Applicability of GPC, GC-MS and 13 C NMR techniques and DFRC method in comparative structural studies of Lignin
More informationEXPERIMENT 7- SAPONIFICATION RATE OF TERT- BUTYL CHLORIDE
1 THEORY EXPERIMENT 7- SAPONIFICATION RATE OF TERT- BUTYL CHLORIDE The field of chemical kinetics is concerned with the rate or speed at which a chemical reaction occurs. Knowledge of a chemical reaction
More informationSOLVOLYSIS OF tert-butyl CHLORIDE: TESTING A MECHANISM
SOLVOLYSIS OF tert-butyl CHLORIDE: TESTING A MECHANISM Organic chemists are keenly interested in how and why chemical reactions occur. They propose a plausible mechanism for a given reaction, then do experiments
More informationORGANIC SYNTHESIS: MICROWAVE-ASSISTED FISCHER ESTERIFICATION
EXPERIMENT 7 ORGANIC SYNTHESIS: MICROWAVE-ASSISTED FISCHER ESTERIFICATION Materials Needed 1.0-2.0 ml of an alcohol to be chosen from the following: 3-methyl 1-butanol (isoamyl alcohol, isopentyl alcohol),
More informationReview Questions for the Chem 2315 Final Exam
Review Questions for the Chem 2315 Final Exam These questions do not have to be turned in, and will not be graded. They are intended to help you review the material we have covered in the lab so far, and
More informationSupporting Information for: Using a Lipase as a High Throughput Screening Method for Measuring the Enantiomeric. Excess of Allylic Acetates
Supporting Information for: Using a Lipase as a High Throughput Screening Method for Measuring the Enantiomeric Excess of Allylic Acetates M. Burak Onaran and Christopher T. Seto* Department of Chemistry,
More informationCH 241 EXPERIMENT #6 WEEK OF NOVEMBER 12, NUCLEOPHILIC SUBSTITUTION REACTIONS (S N 1 and S N 2)
C 241 EXPERIMENT #6 WEEK OF NOVEMBER 12, 2001 NUCLEOPILIC SUBSTITUTION REACTIONS (S N 1 and S N 2) Background By the time you do this experiment we should have covered nucleophilic substitution reactions
More informationSupporting Information for: Anhydrous Tetrabutylammonium Fluoride. Haoran Sun, Stephen G. DiMagno*
Supporting Information for: Anhydrous Tetrabutylammonium Fluoride Haoran Sun, Stephen G. DiMagno* Department of Chemistry, University of Nebraska, Lincoln, NE 68588-0304 Experimental Details Materials
More informationNaBr, H2SO4 CH3CH2CH2CH2Br + NaHSO4 + H2O. 1-Bromobutane bp C den MW n 1.439
Exp t 140 The SN2 Reaction: 1-Bromobutane from K. L. Williamson, Macroscale and Microscale Organic Experiments, 2nd Ed. 1994, Houghton Mifflin, Boston. p247; revised 2/22/02 Prelab Exercise: Review the
More informationLab 2. Go Their Separate Ways: Separation of an Acid, Base, and Neutral Substance by Acid-Base Extraction
Lab 2. Go Their Separate Ways: Separation of an Acid, Base, and Neutral Substance by Acid-Base Extraction How can I use an acid-base reaction to separate an acid-base-neutral mixture? Objectives 1. use
More information