Isobenzofuran by itself is not stable enough to be isolated, but various analogues of it are isolable.
|
|
- Brooke Leonard
- 6 years ago
- Views:
Transcription
1 Diels Alder Class 2 March 8, 2011 Last time we talked a lot about highly reactive dienes, especially those developed by the group of Sam Danishefsky. ne more example of an interesting diene is isobenzofuran: Isobenzofuran by itself is not stable enough to be isolated, but various analogues of it are isolable. Isobenzofuran acts as a diene with the two bonds of the furan (five membered ring) with typical dienophiles: Always remember that you form one more six membered ring in your product than what you started with. What is interesting about isobenzofuran is that it undergoes a retro Diels Alder reaction very easily to lose the oxygen and generate two aromatic rings. Retro Diels Alder reaction just means a reaction in which a ring falls apart through the movement of six electrons simultaneously. So the net result of this type of reaction is that you have replaced a furan ring with an additional aromatic ring. ther dienes also undergo retro Diels Alder reactions. Researchers have used this reaction to synthesize polycyclic aromatic hydrocarbons (PAHs) in general, as you add benzene rings in a linear fashion, the resulting compounds become less and less stable: Pentacene cannot be synthesized by itself, but you can add enough functional groups to stabilize it and synthesize it. ne example of how people can synthesize pentacene is from the Diels Alder reaction of an isobenzofuran (diene) and anthraquinone (dienophile). The retrosynthesis is shown below:
2 R 1 R 1 + X The way this actually worked in the forward direction is shown below: K that will end our discussion of specific dienes, and we will move on to a discussion of dienophiles. First I will go through several common dienophiles and their nomenclature: Most of these (except for acrylonitrile) have two electron withdrawing groups attached to the double bond, which enables these compounds to be highly reactive dienophiles. DMAD has a triple bond, which reacts exactly the same way as the double bonds do in the Diels Alder reaction, however you end up with an additional double bond in your six membered ring product: Cycloalkenones are in general not good dienophiles, because they only have one electron withdrawing group and no other driving force for reactivity:
3 (1) Cyclobutenone ne new dienophile (developed just in 2010) was cyclobutenone: This cyclobutenone reacts very quickly with a variety of dienes, especially compared to the larger ring analogues. The enhanced reactivity is probably due to ring strain making the double bond more reactive. Here is an example of a few Diels Alder reactions with cyclobutenone: The real advantage to these products is that they can easily undergo a variety of ring expansion reactions: And the reason that nobody thought about using cyclobutenone as a dienophile before 2010 is that it is not so easy to synthesize. The synthetic route to cyclobutenone is shown below:
4 (2) ther reactive dienophiles: Several other highly reactive dienophiles are part of hetero diels alder reactions. So far we have mostly talked about diels alder reactions involving six carbon atoms. However, you can replace one or more of those atoms with a heteroatom (nitrogen, oxygen, etc) to generate heterocycle compounds. These are called hetero Diels Alder reactions. The oxo Diels Alder reaction involves a carbonyl compound (where the oxygen itself is one of the six reacting atoms): The aza Diels Alder reaction involves a nitrogen atom in one or both of the reaction partners: The imine that is needed for the aza Diels Alder reaction is often generated in situ (during the reaction) from the reaction of an amine with formaldehyde: via the in situ generated imine: Several common dienophiles used in hetero diels alder reactions are shown below:
5 Imines Diazo compounds: Here s an interesting example that combines something from the last test with new material: In this reaction they use an N heterocyclic carbene to generate an activated enolate / Breslow intermediate from the alpha beta unsaturated aldehyde. This double bond then acts as a dienophile in a hetero Diels Alder reaction. The enolate form is the one that reacts in the Diels Alder reaction. This again adds another interesting option for retrosynthesis. If you look at the lactone product, you could think about making it via an esterification reaction, or via Grubbs at the double bond, but now you can also retrosynthesize it with a hetero Diels Alder reaction.
2. A triple Diels-Alder reaction followed by a triple retro Diels Alder reaction give this interesting product:
Lecture 8 October 6, 2011 Last time we talked a lot about highly reactive dienes, especially those developed by the group of Sam Danishefsky. One more example of an interesting diene is isobenzofuran:
More informationAlso note here that the product is always a six membered ring with a double bond in it.
Diels Alder Class 1 March 3, 2011 I want to talk in some detail over the next few classes about Diels Alder reactions. I am sure that most of you have heard of Diels Alder reactions before, but we will
More informationLuckily this intermediate has three saturated carbons between the carbonyls, which again points to a Michael reaction:
Retrosynthesis Practice Problems Answer Key October 1, 2013 1. Draw a retrosynthesis for how to make the compound shown below from starting materials with eight or fewer carbon atoms. The first step is
More informationPericyclic Reactions and Organic Photochemistry S. Sankararaman Department of Chemistry Indian Institute of Technology, Madras
Pericyclic Reactions and Organic Photochemistry S. Sankararaman Department of Chemistry Indian Institute of Technology, Madras Module No. #02 Lecture No. #08 Pericyclic Reactions -Cycloaddition Reactions
More informationSynthesis Using Aromatic Materials
Chapter 10 Synthesis Using Aromatic Materials ELECTROPHILIC AROMATIC SUBSTITUTION AND DIRECTED ORTHO METALATION Copyright 2018 by Nelson Education Limited 1 10.2 p Bonds Acting as Nucleophiles Copyright
More information23.5 Nucleophilic Substitution in Nitro-Substituted Aryl Halides
23.5 Nucleophilic Substitution in Nitro-Substituted Aryl alides nitro-substituted aryl halides do undergo nucleophilic aromatic substitution readily Cl OC 3 + NaOC 3 C 3 O 85 C + NaCl NO 2 NO 2 (92%) Effect
More information2016 Pearson Education, Inc. Isolated and Conjugated Dienes
2016 Pearson Education, Inc. Isolated and Conjugated Dienes 2016 Pearson Education, Inc. Reactions of Isolated Dienes 2016 Pearson Education, Inc. The Mechanism Double Bonds can have Different Reactivities
More informationSome Answers to Hour Examination #1, Chemistry 302/302A, 2004
Some Answers to our Examination #1, Chemistry 302/302A, 2004 1. In this variation of the Diels-Alder reaction, both the diene and the dienophile are cyclic compounds. The first complication is to decide
More informationDr. Dina akhotmah-232 1
Dr. Dina akhotmah-232 1 Chemistry of polyfunction 1. Types of carbon atom Dr. Dina akhotmah-232 2 Classification of multiple bonds of polyunsaturated compounds Dr. Dina akhotmah-232 3 Organic chemistry,
More informationCHEM 303 Organic Chemistry II Problem Set II Chapter 13 Answers
CEM 303 rganic Chemistry II Problem Set II Chapter 13 Answers 1) Explain the reason for the different chemical reactivity of cyclopentadiene and cycloheptatriene toward bromine. 2 + 2 + oth no doubt start
More informationSome questions and answers that we will get out of this example synthesis:
UTLINE 535 LECTURE 3 (2004) Page 22 The Synthesis of Cubane I am showing you this synthesis because it is elegant and exemplifies many different concepts. We can use it to talk in context about the philosophical
More informationAromatic Hydrocarbons
Aromatic Hydrocarbons Aromatic hydrocarbons contain six-membered rings of carbon atoms with alternating single and double carbon-carbon bonds. The ring is sometimes shown with a circle in the center instead
More informationThe problem is that your product still has a-protons, and can keep on forming enolates to get more methyl groups added:
Lecture 14 ovember 3, 2011 OK I want to continue briefly with the topic of proline catalysis that we discussed last time. In particular, the idea of using secondary amines to catalyze carbonyl chemistry
More informationDiels-Alder Reaction
Diels-Alder Reaction Method for synthesis of 6-membered ring ne-step, concerted reaction Termed [4+2] cycloaddition reaction where 4 and 2 electrons react. + Diels-Alder Reaction Discovered by. Diels and
More information{ReBr(CO) 3 (THF)} 2 (2.5 mol%) 4-Å molecular sieves toluene, 115 o C, 24 h
VII Abstracts 2018 p1 10.2 Product Class 2: Benzo[c]furan and Its Derivatives. Kwiecień This chapter is a revision of the earlier cience of ynthesis contribution describing methods for the synthesis of
More informationCHM 292 Final Exam Answer Key
CHM 292 Final Exam Answer Key 1. Predict the product(s) of the following reactions (5 points each; 35 points total). May 7, 2013 Acid catalyzed elimination to form the most highly substituted alkene possible
More informationAnswers To Chapter 4 Problems.
Answers To Chapter Problems.. (a) An eight-electron [+] cycloaddition. It proceeds photochemically. (b) A four-electron conrotatory electrocyclic ring opening. It proceeds thermally. (c) A six-electron
More informationDiels-Alder Cycloaddition
Diels-Alder ycloaddition A lab practice for the reaction between cyclopentadiene and maleic anhydride The Diels-Alder ycloaddition + onjugated diene Dienophile Diels-Alder reaction: * Stereospecific *
More informationAromatic Compounds. A number of these compounds had a distinct odor. Hence these compounds were called aromatic
Aromatic Compounds Early in the history of organic chemistry (late 18 th, early 19 th century) chemists discovered a class of compounds which were unusually stable A number of these compounds had a distinct
More informationAnswers To Chapter 7 Problems.
Answers To Chapter Problems.. Most of the Chapter problems appear as end-of-chapter problems in later chapters.. The first reaction is an ene reaction. When light shines on in the presence of light and
More informationLecture 13A 05/11/12. Amines. [Sn2; Hofmann elimination; reduction of alkyl azides, amides, nitriles, imines; reductive amination; Gabriel synthesis]
Lecture 13A 05/11/12 Amines [Sn2; ofmann elimination; reduction of alkyl azides, amides, nitriles, imines; reductive amination; Gabriel synthesis] Curtius and ofmann rearrangements Both of these, in principle,
More informationLecture 23. Amines. Chemistry 328N. April 12, 2016
Lecture 23 Amines April 12, 2016 Michael Reaction Michael reaction: conjugate addition of an enolate Arthur Michael anion to an, -unsaturated carbonyl compound!! Following are two examples in the first,
More informationSome questions and answers that we will get out of this example synthesis:
UTLINE CE535 SESSIN 3 (2007) Page 24 The Synthesis of Cubane I am showing you this synthesis because it is elegant and exemplifies many different concepts. We can use it to talk in context about the philosophical
More informationOrganic Chemistry II KEY March 27, 2013
rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI C 1. Rank the dienophiles from most reactive to least reactive in the Diels Alder reaction (most>least) E I II III IV > II > III > IV b) III > I > II
More informationMITOCW watch?v=gboyppj9ok4
MITOCW watch?v=gboyppj9ok4 The following content is provided under a Creative Commons license. Your support will help MIT OpenCourseWare continue to offer high quality educational resources for free. To
More informationISOCHRYSOHERMIDIN. MeO 2 C. MeO. MeO. MeO 2 C OH. Me 1
ISCRYSERMIDI 2 C 2 C 1 ormal demand Diels-Alder (M diene - LUM dienophile ) eutral Diels-Alder Inverse demand Diels-Alder (LUM diene - M dienophile ) EDG EWG EWG EDG LUM LUM LUM M E 1 E 2 E 3 M M E Scheme
More informationOrganic Chemistry II KEY March 27, Which of the following reaction intermediates will form the fastest in the reaction below?
rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 1. Which of the following reaction intermediates will form the fastest in the reaction below? C 1 equiv a 2 a) IV b) III c) II d) II & III e) I I.
More informationChapter 10: Carboxylic Acids and Their Derivatives
Chapter 10: Carboxylic Acids and Their Derivatives The back of the white willow tree (Salix alba) is a source of salicylic acid which is used to make aspirin (acetylsalicylic acid) The functional group
More informationPericyclic reactions
Pericyclic reactions In pericyclic reactions the breaking and making of bonds occur simultaneously by the way of a single cyclic transition state (concerted reaction). There are no intermediates formed
More informationWhen we deprotonate we generate enolates or enols. Mechanism for deprotonation: Resonance form of the anion:
Lecture 5 Carbonyl Chemistry III September 26, 2013 Ketone substrates form tertiary alcohol products, and aldehyde substrates form secondary alcohol products. The second step (treatment with aqueous acid)
More informationB X A X. In this case the star denotes a chiral center.
Lecture 13 Chirality III October 29, 2013 We can also access chiral molecules through the use of something called chiral auxiliaries, which basically is a chiral attachment that you add to your molecule
More informationEnols and Enolates. A type of reaction with carbonyl compounds is an α-substitution (an electrophile adds to the α carbon of a carbonyl)
Enols and Enolates A type of reaction with carbonyl compounds is an α-substitution (an electrophile adds to the α carbon of a carbonyl) E+ E In the preceding chapters, we primarily studied nucleophiles
More informationLecture 24 Two Germans and an Englishman
Lecture 24 Two Germans and an Englishman Robert Robinson 1886-1975 Nobel Laureate 1947 April 17, 2018 tto Paul Hermann Diels 1876-1954 Nobel Laureates 1950 Kurt Alder 1902-1958 Exam III Tomorrow Wed April
More informationHere are a few examples that utilize Jeff Bode s chemistry: 1. Draw the product of the reaction shown below:
Lecture 19 November 29, 2011 Today we will continue our discussion of peptide chemistry, and in particular, focus on two nontraditional ways to make amide bonds. 1. Jeff Bode chemistry: Until this point,
More informationThe mechanism of the nitration of methylbenzene is an electrophilic substitution.
Q1.Many aromatic nitro compounds are used as explosives. One of the most famous is 2-methyl-1,3,5-trinitrobenzene, originally called trinitrotoluene or TNT. This compound, shown below, can be prepared
More information5 Electron Densities, Electrostatic Potentials, and Reactivity Indices (Spartan)
5 Electron Densities, Electrostatic Potentials, and Reactivity Indices (Spartan) Exercise 1 Visualizing Different Bond Types Build the H 2 molecule. Save as dihydrogen.spartan in an appropriate folder.
More informationChemistry Exam 1. The Periodic Table
ame: Last First MI Chemistry 234-002 Exam 1 Spring 2017 Dr. J. sbourn Instructions: The first 18 questions of this exam should be answered on the provided Scantron. You must use a pencil for filling in
More informationOrganic Chemistry II KEY March 25, a) I only b) II only c) II & III d) III & IV e) I, II, III & IV
rganic Chemistry II KEY March 25, 2015 Exam 2: VERSIN A 1. Which of the following compounds will give rise to an aromatic conjugate base? E a) I only b) II only c) II & III d) III & IV e) I, II, III &
More informationORGANIC - CLUTCH CH AROMATICITY.
!! www.clutchprep.com CONCEPT: AROMATICTY INTRODUCTION Aromatic compounds display an unusual stability for their high level of electron density. Their high level of unsaturation should make them extremely
More informationSURVEY ON ARYL COMPOUNDS
Journal of Plastic and Polymer Technology (JPPT) Vol. 1, Issue 1, Jun 2015, 111-132 TJPRC Pvt. Ltd SURVEY ON ARYL COMPOUNDS NAGHAM MAHMOOD ALJAMALI Organic Chemistry, Department of Chemistry, College of
More informationBIOB111 - Tutorial activities for session 8
BIOB111 - Tutorial activities for session 8 General topics for week 4 Session 8 Physical and chemical properties and examples of these functional groups (methyl, ethyl in the alkyl family, alkenes and
More informationLecture Notes Chem 51C S. King Chapter 24 Carbonyl Condensation Reactions
Lecture Notes Chem 51C S. King Chapter 24 Carbonyl Condensation Reactions I. Reaction of Enols & Enolates with ther Carbonyls Enols and enolates are electron rich nucleophiles that react with a number
More informationCOURSE OBJECTIVES / OUTCOMES / COMPETENCIES.
COURSE OBJECTIVES / OUTCOMES / COMPETENCIES. By the end of the course, students should be able to do the following: See Test1-4 Objectives/Competencies as listed in the syllabus and on the main course
More informationSuggested solutions for Chapter 30
s for Chapter 30 30 PRBLEM 1 uggest a mechanism for this synthesis of a tricyclic aromatic heterocycle. 2 Cl base A simple exercise in the synthesis of a pyridine fused to a pyrrole (or an indole with
More informationLoudon Chapter 20 & 21 Review: Carboxylic Acids & Derivatives CHEM 3331, Jacquie Richardson, Fall Page 1
Loudon Chapter 20 & 21 eview: Carboxylic Acids & Derivatives CEM 3331, Jacquie ichardson, Fall 2010 - Page 1 These two chapters cover compounds which are all at the three bonds to more electronegative
More information2. Separate the ions based on their mass to charge (m/e) ratio. 3. Measure the relative abundance of the ions that are produced
I. Mass spectrometry: capable of providing both quantitative and qualitative information about samples as small as 100 pg (!) and with molar masses in the 10 4-10 5 kdalton range A. The mass spectrometer
More informationSaturated heterocycles
Saturated heterocycles Reac0ons of saturated heterocycles Saturated nitrogen heterocycles: amines, but more nucleophilic Reac0ons of saturated heterocycles Saturated nitrogen heterocycles: amines, but
More informationSIX MEMBERED AROMATIC HETEROCYCLES
SIX MEMBERED AROMATIC HETEROCYCLES Ṇ. Pyridine Pyridine is aromatic as there are six delocalized electrons in the ring. Six-membered heterocycles are more closely related to benzene as they are aromatic
More informationChem 1075 Chapter 19 Organic Chemistry Lecture Outline
Chem 1075 Chapter 19 Organic Chemistry Lecture Outline Slide 2 Introduction Organic chemistry is the study of and its compounds. The major sources of carbon are the fossil fuels: petroleum, natural gas,
More informationORGANIC CHEMISTRY. Fifth Edition. Stanley H. Pine
ORGANIC CHEMISTRY Fifth Edition Stanley H. Pine Professor of Chemistry California State University, Los Angeles McGraw-Hill, Inc. New York St. Louis San Francisco Auckland Bogota Caracas Lisbon London
More informationKey ideas: In EAS, pi bond is Nu and undergoes addition.
Objective 7. Apply addition and elimination concepts to predict electrophilic aromatic substitution reactions (EAS) of benzene and monosubstituted benzenes. Skills: Draw structure ID structural features
More informationChapter 13. Conjugated Unsaturated Systems. +,., - Allyl. What is a conjugated system? AllylicChlorination (High Temperature)
What is a conjugated system? Chapter 13 Conjugated Unsaturated Systems Conjugated unsaturated systems have a p orbital on a carbon adjacent to a double bond The p orbital may be empty (a carbocation The
More informationChemistry Final Examinations Summer 2006 answers
Chemistry 235 - Final Examinations Summer 2006 answers A GEERAL CEMISTRY answers are given from 1-20: no reaction C 3 CC 3 Ph C C C C C 3 Et 2 2 2 B. REACTIS AD REAGETS [32 MARKS] 2. A single substance
More informationLoudon Chapter 15 Review: Dienes and Aromaticity Jacquie Richardson, CU Boulder Last updated 1/28/2019
This chapter looks at the behavior of carbon-carbon double bonds when several of them are in the same molecule. There are several possible ways they can be grouped. Conjugated dienes have a continuous
More informationMCAT Organic Chemistry Problem Drill 10: Aldehydes and Ketones
MCAT rganic Chemistry Problem Drill 10: Aldehydes and Ketones Question No. 1 of 10 Question 1. Which of the following is not a physical property of aldehydes and ketones? Question #01 (A) Hydrogen bonding
More informationChapter 25: The Chemistry of Life: Organic and Biological Chemistry
Chemistry: The Central Science Chapter 25: The Chemistry of Life: Organic and Biological Chemistry The study of carbon compounds constitutes a separate branch of chemistry known as organic chemistry The
More informationChapter 19. Synthesis and Reactions of b-dicarbonyl Compounds: More Chemistry of Enolate Anions. ß-dicarbonyl compounds. Why are ß-dicarbonyls useful?
Chapter 19 Synthesis and Reactions of b-dicarbonyl Compounds: More Chemistry of Enolate Anions ß-dicarbonyl compounds Two carbonyl groups separated by a carbon Three common types ß-diketone ß-ketoester
More informationChapter 15 Dienes, Resonance, and Aromaticity
Instructor Supplemental Solutions to Problems 2010 Roberts and Company Publishers Chapter 15 Dienes, Resonance, and Aromaticity Solutions to In-Text Problems 15.2 The delocalization energy is the energy
More information25.3 THE CHEMISTRY OF FURAN, PYRROLE, AND THIOPHENE
6 CAPTER 5 TE CEMITRY F TE ARMATIC ETERCYCE B. Acidity of Pyrrole and Indole Pyrrole and indole are weak acids. + B _ etc. + B 4 _ (a base) _ (5.9) Further Exploration 5. Relative Acidities of,-cyclopentadiene
More informationTHE DIELS-ALDER REACTION
22.6 TE DIELS-ALDER REATIN 977 2 Both overlaps are bonding. ± 2 ± 2 2 M of the diene LUM of the alkene ( 2 ) (*) The [ + 2] cycloaddition is allowed by a thermal pathway. Both overlaps are bonding, so
More informationLecture Notes Chemistry Mukund P. Sibi Lecture 36 Synthesis of Amines
Lecture otes hemistry 42-2008 Mukund P. Sibi Synthesis of Amines Amines can be prepared from a variety of starting materials. All of these methods involve functional group transformations. The main methods
More informationHow to make pyridines: the Hantzsch pyridine synthesis
ow to make pyridines: the antzsch pyridine synthesis 1191 Zinc in acetic acid (Chapter 24) reduces the oxime to the amine and we can start the synthesis by doing the conjugate addition and then reducing
More informationCHAPTER 16 CONJUGATE ADDITION
HAPTER 16 NJUGATE ADDITIN onjugated Pi Bonds onjugated double bonds are separated by only one single bond. Isolated double bonds are separated by two or more single bonds. arbonyl ompounds with onjugated
More information2.222 Practice Problems 2003
2.222 Practice Problems 2003 Set #1 1. Provide the missing starting compound(s), reagent/solvent, or product to correctly complete each of the following. Most people in the class have not done this type
More informationPage 1 of 9. Sessional Examination (November 2017) Max Marks: 20 Date: Time: One Hour. Model Answers
Page 1 of 9 Sessional Examination (November 2017) Class: B. Pharm-II yr (III sem) Subject: Pharma Org. Chem-II Max Marks: 20 Date: 14.11.2017 Time: One Hour Model Answers Q. 1. Solve the following (ANY
More informationSynthetic Organic Chemistry Final Exam (6KM33) Tuesday, 8th April, 2014, 9:00 12:00 (3 h)
Synthetic rganic Chemistry Final Exam (6KM33) Tuesday, 8th April, 2014, 9:00 12:00 (3 h) This is an open-book written exam. The course textbooks (Warren & Wyatt, 2 nd Ed.) with personal notes and worked
More informationOrganic Chemistry Paula Y. Bruice Seventh Edition
rganic hemistry Paula Y. Bruice Seventh Edition Pearson Education Limited Edinburgh Gate arlow Essex M20 2JE England and Associated ompanies throughout the wld Visit us on the Wld Wide Web at: www.pearsoned.co.uk
More informationFundamentals of Organic Chemistry
Fundamentals of Organic Chemistry CHEM 109 For Students of Health Colleges Credit hrs.: (2+1) King Saud University College of Science, Chemistry Department CHEM 109 CHAPTER 3. AROMATIC HYDROCARBONS Aromatic
More informationBenzene and Aromatic Compounds. Chapter 15 Organic Chemistry, 8 th Edition John McMurry
Benzene and Aromatic Compounds Chapter 15 Organic Chemistry, 8 th Edition John McMurry 1 Background Benzene (C 6 H 6 ) is the simplest aromatic hydrocarbon (or arene). Four degrees of unsaturation. It
More informationConjugated Dienes and Ultraviolet Spectroscopy
Conjugated Dienes and Ultraviolet Spectroscopy Key Words Conjugated Diene Resonance Structures Dienophiles Concerted Reaction Pericyclic Reaction Cycloaddition Reaction Bridged Bicyclic Compound Cyclic
More informationChem 263 March 7, 2006
Chem 263 March 7, 2006 Aldehydes and Ketones Aldehydes and ketones contain a carbonyl group, in which the carbon atom is doubly bonded to an oxygen atom. The carbonyl group is highly polarized, with a
More informationLecture 3: Aldehydes and ketones
Lecture 3: Aldehydes and ketones I want to start by talking about the mechanism of hydroboration/ oxidation, which is a way to get alcohols from alkenes. This gives the anti-markovnikov product, primarily
More information17.1 Classes of Dienes
17.1 Classes of Dienes There are three categories for dienes: Cumulated: pi bonds are adjacent. Conjugated: pi bonds are separated by exactly ONE single bond. Isolated: pi bonds are separated by any distance
More information10.12 The Diels-Alder Reaction. Synthetic method for preparing compounds containing a cyclohexene ring
10.12 The Diels-Alder Reaction Synthetic method for preparing compounds containing a cyclohexene ring In general... + conjugated diene alkene (dienophile) cyclohexene via transition state Mechanistic features
More informationLab #5: Electron Densities, Electrostatic Potentials, and Reactivity Indices
Lab #5: Electron Densities, Electrostatic Potentials, and Reactivity Indices Exercise 1 - Visualizing Different Bond Types Build H 2 and perform a geometry optimization (Mopac) using the choices shown
More informationChapter 12: Carbonyl Compounds II
Chapter 12: Carbonyl Compounds II Learning bjectives: 1. Recognize and assign names to aldehydes and ketones. 2. Write the mechanism for nucleophilic addition and nucleophilic addition-elimination reactions
More informationKJM 3200 Required Reading (Pensum), Fall 2016
KJM 3200 Required Reading (Pensum), Fall 2016 John McMurry: Organic Chemistry 8 nd ed. or Paula Y. Bruice, Organic Chemistry 7 nd ed. as specified below, as specified below. Lise-Lotte Gundersen KJM 3200.
More information4. AROMATIC COMPOUNDS
BOOKS 1) Organic Chemistry Structure and Function, K. Peter C. Vollhardt, Neil Schore, 6th Edition 2) Organic Chemistry, T. W. Graham Solomons, Craig B. Fryhle 3) Organic Chemistry: A Short Course, H.
More informationCHEM 263 Notes Oct 1, Beta-carotene (depicted below) is responsible for the orange-red colour in carrots.
EM 263 otes ct 1, 2013 onjugated Dienes and olour ontinued Beta-carotene (depicted below) is responsible for the orange-red colour in carrots. In the below example, astaxanthin, a blue-green pigment in
More informationChapter 1 Reactions of Organic Compounds. Reactions Involving Hydrocarbons
Chapter 1 Reactions of Organic Compounds Reactions Involving Hydrocarbons Reactions of Alkanes Single bonds (C-C) are strong and very hard to break, therefore these compounds are relatively unreactive
More informationAmines and Heterocycles. McMurry: Chapter 24
Amines and Heterocycles McMurry: Chapter 24 Introduction to Amines and Heterocycles Amines and heterocycles (cyclic amines) are ammonia derivatives, many of whichare found widely in livingorganisms: 2
More informationChapter 9. Organic Chemistry: The Infinite Variety of Carbon Compounds. Organic Chemistry
Chapter 9 Organic Chemistry: The Infinite Variety of Carbon Compounds Organic Chemistry Organic chemistry is defined as the chemistry of carbon compounds. Of tens of millions of known chemical compounds,
More information21.1 Introduction Carboxylic Acids Nomenclature of Carboxylic Acids. Acids Structure and Properties of Carboxylic Acids.
21.1 Introduction Carboxylic Acids Carboxylic acids are abundant in nature and in pharmaceuticals. 21.1 Introduction Carboxylic Acids The US produces over 2.5 million tons of acetic acid per year, which
More informationN-Heterocyclic Carbene Catalysis via Azolium Dienolates: An Efficient Strategy for Enantioselective Remote Functionalizations
Angew. Chem. Int. Ed. 2017, 10.1002. 1 N-Heterocyclic Carbene Catalysis via Azolium Dienolates: An Efficient Strategy for Enantioselective Remote Functionalizations Reporter: En Li Supervisor: Prof. Yong
More informationJEFFERSON COLLEGE COURSE SYLLABUS CHM201 ORGANIC CHEMISTRY II. 5 Credit Hours. Prepared by: Richard A. Pierce
JEFFERSON COLLEGE COURSE SYLLABUS CHM201 ORGANIC CHEMISTRY II 5 Credit Hours Prepared by: Richard A. Pierce Revised Date: January 2008 by Ryan H. Groeneman Arts & Science Education Dr. Mindy Selsor, Dean
More informationTable 8.2 Detailed Table of Characteristic Infrared Absorption Frequencies
Table 8.2 Detailed Table of Characteristic Infrared Absorption Frequencies The hydrogen stretch region (3600 2500 cm 1 ). Absorption in this region is associated with the stretching vibration of hydrogen
More informationOrganic Chemistry CHM 224
rganic Chemistry CM 224 Final Exam Review Questions This is a compilation example final exam questions. Provide IUPAC names for each of the structures below. 2 ! Propose a structure for the compound that
More informationb.(12) Where is pyrrole protonated under strong acidic conditions? Why this site of protonation?
1. Rank the following compounds in the trend requested. (15 points each) a. Rank the following dienes by rate of Diels-Alder reaction. The diene which reacts the fastest with an alkene is 1, while the
More informationDr. Mohamed El-Newehy
By Dr. Mohamed El-Newehy Chemistry Department, College of Science, King Saud University http://fac.ksu.edu.sa/melnewehy Aldehydes and Ketones 1 Structure of Aldehydes and Ketones - Aldehydes and ketones
More informationSolution problem 22: Non-Benzoid Aromatic Sytems
Solution problem 22: on-enzoid Aromatic Sytems 22.1 & 22.2 Each double bond and each heteroatom (, ) with lone pairs donates 2 π- electrons as well as a negative charge. oron or a positive charge does
More informationAldol Reactions pka of a-h ~ 20
Enolate Anions Chapter 17 Hydrogen on a carbons a to a carbonyl is unusually acidic The resulting anion is stabilized by resonance to the carbonyl Aldehydes and Ketones II Aldol Reactions pka of a-h ~
More informationChapter 13 Conjugated Unsaturated Systems
Chapter 13 Conjugated Unsaturated Systems Introduction Conjugated unsaturated systems have a p orbital on a carbon adjacent to a double bond The p orbital can come from another double or triple bond The
More informationChemistry 3720 Old Exams. Practice Exams & Keys
Chemistry 3720 ld Exams Practice Exams & Keys 2015-17 Spring 2017 Page File 3 Spring 2017 Exam 1 10 Spring 2017 Exam 1 Key 16 Spring 2017 Exam 2 23 Spring 2017 Exam 2 Key 29 Spring 2017 Exam 3 36 Spring
More informationICOMST st International Congress of Meat Science & Technology MECHANISTIC PATHWAYS TO PROCESS-INDUCED TOXICANTS IN MEAT
ICOMST 2015 61st International Congress of Meat Science & Technology MECHANISTIC PATHWAYS TO PROCESS-INDUCED TOXICANTS IN MEAT Content General introduction Summary of chemical reactions generating toxicants
More informationCHE 322 Summer 2012 Final Exam Form Choose the lowest unoccupied molecular orbital (LUMO) of the pentadienyl cation.
Multiple Choice Questions: 100 points 1. Choose the lowest unoccupied molecular orbital (LUMO) of the pentadienyl cation. 2. Select the possible reactants of the following reaction. A i B ii C iii D i
More informationLecture Notes Chem 51B S. King I. Conjugation
Lecture Notes Chem 51B S. King Chapter 16 Conjugation, Resonance, and Dienes I. Conjugation Conjugation occurs whenever p-orbitals can overlap on three or more adjacent atoms. Conjugated systems are more
More information11/5/ Conjugated Dienes. Conjugated Dienes. Conjugated Dienes. Heats of Hydrogenation
8.12 Sites of unsaturation Many compounds have numerous sites of unsaturation If sites are well separated in molecule they react independently If sites are close together they may interact with one another
More informationAdvanced Organic Chemistry: Retrosynthesis
123.312 Advanced rganic Chemistry: Retrosynthesis Tutorial Question 1. Propose a retrosynthetic analysis of the following two compounds. Your answer should include both the synthons, showing your thinking,
More informationThe problem is that your product still has a-protons, and can keep on forming enolates to get more methyl groups added:
Lecture 13 Notes November 7, 2012 We are going to start with some examples of proline-catalyzed reactions. In each case, you can draw a mechanism that would involve proline as a chiral catalyst, and one
More informationDiels Alder cycloaddition
I p1.1.1 The Diels Alder Cycloaddition Reaction in the Context of Domino Processes J. G. West and E. J. Sorensen The Diels Alder cycloaddition has been a key component in innumerable, creative domino transformations
More information