15.10 Effect of Substituents on Reactivity and Orientation
|
|
- Chad Lucas
- 6 years ago
- Views:
Transcription
1 15.10 ffect of Substituents on Reactivity and Orientation
2 Z NO 3 2 SO 4 Z Z Z + + o- p- m- Z O Me CN o(%) p(%) <1 2 m(%) <
3 C 3 An activating group Ortho-para director An deactivating group Meta director More reactive than benzene toward electrophilic substitution Less reactive than benzene toward electrophilic substitution X An deactivating group Ortho-para directors Less reactive than benzene toward electrophilic substitution
4 Ortho-para directors NR 2 NR N 2 O OR NCOR OCOR R C 6 5 X Meta directors NR 3 C 3 CN SO 3 CO COR CO 2 R CON 2
5 15.11 Theory of Substituent ffects on lectrophilic Aromatic Substitution
6 Q Q Q δ δ + δ δ δ + Q releases electrons + δ Reaction is faster Q Q Q δ + δ δ + δ + δ Q withdraws electrons + δ Reaction is slower
7 R R R R R R R + + R R R
8 + +
9 + +
10 Orientation of Disubstituted Benzenes C 3 C 3 NO 3 2 SO 4 C 3 2 Fe 3 C 3 + C 3
11 C 3 CO 2 NCOC 3 N 2 C 3 CO 2 CO 2
12 C 3 CO 2 N 2 C 3 NCOC 3
13 15.12 Reactions of the Side Chain of Alkylbenzenes
14 C 3 C 2 C hv or heat + Br 2 hv or heat Br C 2 CC 3
15 15.13 Alkenylbenzenes
16 15.13A Stability of Conjugated Alkenylbenzene C C C more stable than C C C
17 15.13B Addition to the Double Bond of Alkenylbenzenes C CC 3 Br peroxide C 2 CC 3 Br C CC 3 Br C C 2 C 3 Br
18 15.13C Oxidation of the Side Chain C 3 C 2 C 3 KMnO4 CO 2 C(C 3 ) 2 C(C 3 ) 3 KMnO4
19 15.13D Oxidation of the Benzene Ring R C 6 5 (1) O 3, OAc (2) 2 O 2 R CO 2 KMnO 4 K 2 Cr 2 O 7 / + V 2 O 5 + O ~ 500 O O + CO O O Maleic anhydride
20 15.14 Synthetic Applications
21 When designing a synthesis of substituted benzenes, the order in which the substituents are introduced is crucial xample: Synthesize ortho-, meta-, and para-nitrobenzoic acid from toluene NO SO 4 Fe
22
23 15.14A Use of Protecting and Blocking Groups Strong activating groups such as amino and hydroxyl cause the aromatic ring to be so reactive that unwanted reactions can take place. These groups activate aromatic rings to oxidation by nitric acid when nitration is attempted; the ring is destroyed. O NO 3 2 SO 4 O O + + Oxidation products Low yield
24 N 2 NO 3 N 3 N 3 NO 3 2 SO 4 2 SO 4 An amino group or hydroxyl group can be protected (and turned into a moderately activating group) by acetylation. N 2 C 3 CO or (C 3 CO) 2 O NCOC 3 Base O Acylation OCOC 3 C 3 CO or (C 3 CO) 2 O Base Protecting groups
25 xample: The synthesis of p- and o- nitroaniline from aniline N 2 C 3 CO NCOC 3 NCOC 3 NCOC 3 Base NO 3 2 SO 4 + Aniline Acetanilide p-nitroacetanilide o-nitroacetanilide N 2 (90%) (trace) (1) 2 O, +, C 3 CO 2 + (2) O p-nitroaniline
26 A sulfonic acid group is used as a blocking group to force ortho substitution NCOC 3 concd. 2 SO 4 NCOC 3 NO 3 NCOC 3 2 SO 4 SO 3 SO 3 N 2 (1) 2 O, +, (2) O o-nitroaniline (56%)
27 15.14B Orientation in Disubstituted Benzenes When two substituents are present on the ring initially, the more powerful activating group generally determines the orientation of subsequent substitution Ortho-para directors determine orientation over meta directors Substitution does not occur between meta substituents due to steric hindrance
28 NCOC 3 2 C 3 CO 2 NCOC 3 + NCOC 3 C 3 C 3 (major product) C 3 (minor product) NO 3 2 SO 4 Br O 2 N + + Br Br Br (62%) (37%) (1%)
29 15.15 Allylic and Benzylic alides in Nucleophilic Substitution Reactions
30 Allylic and benzylic halides are classified in similar fashion to other halides C C C 2 X C R C C X R C C C X R' 1 Allylic 2 Allylic 3 Allylic R R Ar C 2 X Ar C X Ar C X R' 1 Benzylic 2 Benzylic 3 Benzylic
31 Both primary and secondary allylic and benzylic halides can undergo S N 1 or S N 2 reaction These primary halides are able to undergo S N 1 reaction because of the added stability of the allylic and benzylic carbocation Tertiary allylic and benzylic halides can only undergo S N 1 reaction
32
33 15.16 Reductions of Aromatic Compounds
34 Birch Reduction Ni, Pd, or Pt 180 ~ 250, P N 3 (liq.) + Na to K, Li OC 3 Na or Li N 3 (l), to OC 3 2 O + O CO 2 Na or Li N 3 (l), to CO 2
12/27/2010. Chapter 15 Reactions of Aromatic Compounds
Chapter 15 Reactions of Aromatic Compounds Electrophilic Aromatic Substitution Arene (Ar-H) is the generic term for an aromatic hydrocarbon The aryl group (Ar) is derived by removal of a hydrogen atom
More informationChapter 15 Reactions of Aromatic Compounds
Chapter 15 1 Chapter 15 Reactions of Aromatic Compounds Electrophilic Aromatic Substitution Arene (Ar-H) is the generic term for an aromatic hydrocarbon The aryl group (Ar) is derived by removal of a hydrogen
More informationChapter 15. Reactions of Aromatic Compounds. Electrophilic Aromatic Substitution on Arenes. The first step is the slow, rate-determining step
Electrophilic Aromatic Substitution on Arenes Chapter 15 Reactions of Aromatic Compounds The characteristic reaction of aromatic rings is substitution initiated by an electrophile halogenation nitration
More information08. Chemistry of Benzene: Electrophilic Aromatic Substitution. Based on McMurry s Organic Chemistry, 6 th edition, Chapter 16
08. Chemistry of Benzene: Electrophilic Aromatic Substitution Based on McMurry s Organic Chemistry, 6 th edition, Chapter 16 Benzene is a nucleophile p electrons make benzene nucleophile, like alkenes.
More informationElectrophilic Aromatic Substitution (Aromatic compounds) Ar-H = aromatic compound 1. Nitration Ar-H + HNO 3, H 2 SO 4 Ar-NO 2 + H 2 O 2.
Electrophilic Aromatic Substitution (Aromatic compounds) Ar- = aromatic compound 1. Nitration Ar- + NO 3, 2 SO 4 Ar- + 2 O 2. Sulfonation Ar- + 2 SO 4, SO 3 Ar-SO 3 + 2 O 3. alogenation Ar- + X 2, Fe Ar-X
More information11/30/ Substituent Effects in Electrophilic Substitutions. Substituent Effects in Electrophilic Substitutions
Chapter 9 Problems: 9.1-29, 32-34, 36-37, 39-45, 48-56, 58-59, 61-69, 71-72. 9.8 Substituent effects in the electrophilic substitution of an aromatic ring Substituents affect the reactivity of the aromatic
More informationElectrophilic Aromatic Substitution
Lecture 12 Electrophilic Aromatic Substitution E E February 22, 2018 Electrophilic Aromatic Substitution Electrophilic aromatic substitution: a reaction in which a hydrogen atom on an aromatic ring is
More informationChapter 16 Chemistry of Benzene: Electrophilic Aromatic Substitution
John E. McMurry www.cengage.com/chemistry/mcmurry Chapter 16 Chemistry of Benzene: Electrophilic Aromatic Substitution Paul D. Adams University of Arkansas Substitution Reactions of Benzene and Its Derivatives
More informationOrganic Chemistry. M. R. Naimi-Jamal. Faculty of Chemistry Iran University of Science & Technology
Organic Chemistry M. R. Naimi-Jamal Faculty of Chemistry Iran University of Science & Technology Chapter 5-2. Chemistry of Benzene: Electrophilic Aromatic Substitution Based on McMurry s Organic Chemistry,
More informationCHEM Chapter 16. Chemistry of Benzene: Electrophilic Aromatic Substitution (homework) W
CHEM 2425. Chapter 16. Chemistry of Benzene: Electrophilic Aromatic Substitution (homework) W Short Answer Exhibit 16-1 MATCH a structure or term from the following list with each description below. Place
More informationChapter 13 Reactions of Arenes Electrophilic Aromatic Substitution
. 13 hapter 13 eactions of Arenes lectrophilic Aromatic ubstitution lectrophiles add to aromatic rings in a fashion somewhat similar to the addition of electrophiles to alkenes. ecall: 3 4 Y 1 4 2 1 δ
More informationChemistry 204: Benzene and Aromaticity
Chemistry 204: Benzene and Aromaticity Structure of and Bonding in Benzene benzene, C 6 H 6, was first isolated in 1825 (Michael Faraday), but it was not until more than 100 years later that an adequate
More informationCHAPTER 16 - CHEMISTRY OF BENZENE: ELECTROPHILIC AROMATIC SUBSTITUTION
CAPTR 16 - CMISTRY F BNZN: LCTRPILIC ARMATIC SUBSTITUTIN As stated in the previous chapter, benzene and other aromatic rings do not undergo electrophilic addition reactions of the simple alkenes but rather
More informationChapter 17. Reactions of Aromatic Compounds
Chapter 17 Reactions of Aromatic Compounds Electrophilic Aromatic Substitution Although benzene s pi electrons are in a stable aromatic system, they are available to attack a strong electrophile to give
More information16. Chemistry of Benzene: Electrophilic Aromatic Substitution. Based on McMurry s Organic Chemistry, 7 th edition
16. Chemistry of Benzene: Electrophilic Aromatic Substitution Based on McMurry s Organic Chemistry, 7 th edition Substitution Reactions of Benzene and Its Derivatives Benzene is aromatic: a cyclic conjugated
More informationChapter 15. Reactions of Aromatic Compounds. 1. Electrophilic Aromatic Substitution Reactions
hapter 15 eactions of Aromatic ompounds 1. Electrophilic Aromatic Substitution eactions v verall reaction reated by Professor William Tam & Dr. Phillis hang opyright S 3 2 S 4 S 3 2. A General Mechanism
More information16. Chemistry of Benzene: Electrophilic Aromatic Substitution جانشینی الکتروندوستی آروماتیک شیمی آلی 2
16. Chemistry of Benzene: Electrophilic Aromatic Substitution جانشینی الکتروندوستی آروماتیک شیمی آلی 2 Dr M. Mehrdad University of Guilan, Department of Chemistry, Rasht, Iran m-mehrdad@guilan.ac.ir Based
More information16. Chemistry of Benzene: Electrophilic Aromatic Substitution جانشینی الکتروندوستی آروماتیک شیمی آلی 2
16. Chemistry of Benzene: Electrophilic Aromatic Substitution جانشینی الکتروندوستی آروماتیک شیمی آلی 2 Dr M. Mehrdad University of Guilan, Department of Chemistry, Rasht, Iran m-mehrdad@guilan.ac.ir Based
More informationChapter 17 Reactions of Aromatic Compounds. Electrophilic Aromatic Substitution
Chapter 17 Reactions of Aromatic Compounds Electrophilic Aromatic Substitution Electrophile substitutes for a hydrogen on the benzene ring. Chapter 17: Aromatics 2-Reactions Slide 17-2 1 Mechanism Step
More informationExamples of Substituted Benzenes
Organic Chemistry 5 th Edition Paula Yurkanis Bruice Examples of Substituted Benzenes Chapter 15 Reactions of Substituted Benzenes Irene Lee Case Western Reserve University Cleveland, OH 2007, Prentice
More informationCh.16 Chemistry of Benzene: Electrophilic Aromatic Substitution
Ch.16 Chemistry of Benzene: Electrophilic Aromatic Substitution Electrophilic aromatic substitution: E + E + + Some electrophilic aromatic substitution: X N 2 S 3 R C R alogenation Nitration Sulfonation
More informationNitration of (Trifluoromethyl( Trifluoromethyl)benzene CF 3 HNO 3 + +
Effect on Rate Rate and Regioselectivity in Electrophilic Aromatic Substitution A substituent already present on the ring affects both the rate and regioselectivity of electrophilic aromatic substitution.
More informationORGANIC - BROWN 8E CH. 22- REACTIONS OF BENZENE AND ITS DERIVATIVES
!! www.clutchprep.com CONCEPT: ELECTROPHILIC AROMATIC SUBSTITUTION GENERAL MECHANISM Benzene reacts with very few reagents. It DOES NOT undergo typical addition reactions. Why? If we can get benzene to
More informationChemistry of Benzene: Electrophilic Aromatic Substitution
Chemistry of Benzene: Electrophilic Aromatic Substitution Why this Chapter? Continuation of coverage of aromatic compounds in preceding chapter focus shift to understanding reactions Examine relationship
More informationChapter 12. Reactions of Arenes: Electrophilic Aromatic Substitution. Class Notes. A. The method by which substituted benzenes are synthesized
Chapter 12 Reactions of Arenes: Electrophilic Aromatic Substitution Chapter 12 suggested problems: 22, 23, 26, 27, 32, 33 Class Notes I. Electrophilic aromatic substitution reactions A. The method by which
More informationChapter 19: Aromatic Substitution Reactions
Chem A225 Notes Page 52 Chapter 19: Aromatic Substitution Reactions Topic One: lectrophilic Aromatic Substitution I. Introduction to lectrophilic Aromatic Substitution (AS) A. eneral Reaction Pattern B.
More informationChapter 5. Aromatic Compounds
Chapter 5. Aromatic Compounds 5.1 Structure of Benzene: The Kekule Proposal Mid-1800s, benzene was known to have the molecular formula C 6 6. Benzene reacts with 2 in the presence of iron to give substitution
More informationAromatic Compounds II
2302272 Org Chem II Part I Lecture 2 Aromatic Compounds II Instructor: Dr. Tanatorn Khotavivattana E-mail: tanatorn.k@chula.ac.th Recommended Textbook: Chapter 17 in Organic Chemistry, 8 th Edition, L.
More informationMarch 08 Dr. Abdullah Saleh
March 08 Dr. Abdullah Saleh 1 Effects of Substituents on Reactivity and Orientation The nature of groups already on an aromatic ring affect both the reactivity and orientation of future substitution Activating
More informationBENZENE AND AROMATIC COMPOUNDS
BENZENE AND AROMATIC COMPOUNDS The discovery of benzene: 1825 - Michael Faraday, empirical formula of C 1834 - Eilhard Mitscherlich synthesized benzin from gum benzoin, empirical formula C Aromatic The
More informationOrganic Chemistry, 7 L. G. Wade, Jr. Chapter , Prentice Hall
Organic Chemistry, 7 th Edition L. G. Wade, Jr. Chapter 17 Reactions of Aromatic Compounds 2010, Prentice Hall Electrophilic Aromatic Substitution Although h benzene s pi electrons are in a stable aromatic
More informationBenzenes & Aromatic Compounds
Benzenes & Aromatic Compounds 1 Structure of Benzene H H C C C H C 6 H 6 H C C C H H A cyclic conjugate molecule Benzene is a colourless odourless liquid, boiling at 80 o C and melting at 5 o C. It is
More informationLearning Guide for Chapter 18 - Aromatic Compounds II
Learning Guide for Chapter 18 Aromatic Compounds. lectrophilic aromatic substitution ntroduction Mechanism Reagents and Products lectrophiles ffects of stituents FriedelCrafts alkylation and acylation
More informationH 2 SO 4 Ar-NO 2 + H2O
Phenyl group: Shorthand for phenyl: Ph, C 6 5,. An aryl group is an aromatic group: phenyl, substituted phenyl, or other aromatic group. Shorthand: Ar Generalized electrophilic aromatic substitution: E
More informationMore EAS. Lecture 12. Di- and Polysubstitution CH 3 + H + H HNO 2 NO 2. February 25, /25/16 OCH 3 OCH OCH. o-nitro-anisole (31%) Anisole
Lecture 12 More EAS February 25, 2016 Di- and Polysubstitution O O OC OC 3 3 NO 3 2 SO 4 Anisole o-nitro-anisole (31%) m-nitro-anisole (2%) p-nitro-anisole (67%) l -O is ortho-para directing and activating
More informationLecture Topics: I. Electrophilic Aromatic Substitution (EAS)
Reactions of Aromatic Compounds Reading: Wade chapter 17, sections 17-1- 17-15 Study Problems: 17-44, 17-46, 17-47, 17-48, 17-51, 17-52, 17-53, 17-59, 17-61 Key Concepts and Skills: Predict and propose
More informationWilliam H. Brown & Christopher S. Foote
William. Brown & Christopher S. Foote Requests for permission to make copies of any part of the work should be mailed to:permissions Department, arcourt Brace & Company, 6277 Sea arbor Drive, Orlando,
More informationElectrophilic Aromatic Substitution
Chem 263 Sept 29, 2016 lectrophilic Aromatic Substitution Benzene appears to be a remarkably stable (36 kcal/mole more) and unreactive compared to alkenes, such as cyclohexene or ethylene, or even alkanes,
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 informationChapter 19: Benzene and Aromatic Substitution Reactions [Sections: 18.2, 18.6; ]
Chapter 19: Benzene and Aromatic Substitution eactions [Sections: 18.2, 18.6; 19.1-19.12] omenclature of Substituted Benzenes i. Monosubstituted Benzenes C 2 C 3 ii. Disubstituted Benzenes X X X Y Y Y
More informationElectrophilic Aromatic Substitution
Chem 263 ct. 8, 2013 lectrophilic Aromatic Substitution Benzene appears to be a remarkably stable and unreactive compared to alkenes, such as cyclohexene or ethylene, or even alkanes, such as cyclohexane
More informationTOPIC 2. REACTIONS OF AROMATIC COMPOUNDS (Chapters 15, parts of 20, and 21)
L TPIC 2. RACTINS F ARMATIC CMPUNDS (Chapters 15, parts of 20, and 21) BJCTIVS 1. Describe the reactions between strong electrophiles and aromatic compounds (the nucleophilc component) which lead to substitution
More informationCh 16 Electrophilic Aromatic Substitution
Ch 16 Electrophilic Aromatic Substitution Mechanism - Aromatic rings typically undergo substitution, where an H is replaced with an electrophile (E+). - The rings do not typically undergo addition across
More informationChapter 16. Chemistry of Benzene: Electrophilic Aromatic Substitution. Reactivity of Benzene
hapter 16 hemistry of Benzene: Electrophilic Aromatic Substitution Reactivity of Benzene - stabilization due to aromaticity makes benzene significantly less reactive than isolated alkenes 2 no reaction
More informationChapter 17 Reactions of Aromatic Compounds
rganic Chemistry, 6 th Edition L. G. Wade, Jr. Chapter 17 Reactions of Aromatic Compounds Jo Blackburn Richland College, Dallas, TX Dallas County Community College District 2006, Prentice all Electrophilic
More informationReactions of Aromatic Compounds
2-1 Reactions of Aromatic Compounds 15.1 2-2 lectrophilic Aromatic Substitution Reactions Aromatic hydrocarbons (= arenes) undergo a substitution reaction with electrophiles: + catalyst + xample: omination
More informationTreatment of cyclooctatetrene with potassium gives you a dianion. Classify the starting material and product as aromatic, antiaromatic or
Treatment of cyclooctatetrene with potassium gives you a dianion. Classify the starting material and product as aromatic, antiaromatic or nonaromatic? 1 2 Classify cyclononatetrene and it s various ions
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 informationChem 263 Oct. 6, Single bonds, σ. e - donating Activate Activate ortho and para directing ortho and para directing
Chem 263 ct. 6, 2009 lectrophilic Substitution of Substituted Benzenes Resonance ffect Inductive ffect C=C, π system Single bonds, σ Strong Weak e - donating Activate Activate ortho and para directing
More informationOrganic Chemistry. Second Edition. Chapter 19 Aromatic Substitution Reactions. David Klein. Klein, Organic Chemistry 2e
Organic Chemistry Second Edition David Klein Chapter 19 Aromatic Substitution Reactions Copyright 2015 John Wiley & Sons, Inc. All rights reserved. Klein, Organic Chemistry 2e 19.1 Introduction to Electrophilic
More informationChapter 17: Reactions of Aromatic Compounds
1 Chapter 17: Reactions of Aromatic Compounds I. Introduction to Electrophilic Aromatic Substitution (EAS) A. General Mechanism II. Reactions of Electrophilic Aromatic Substitution A. Halogenation (E =
More informationC h a p t e r N i n e t e e n Aromatics II: Reactions of Benzene & Its Derivatives
C h a p t e r N i n e t e e n Aromatics II: Reactions of Benzene & Its Derivatives Arenium ion from addition of tert-butyl cation to benzene (blue is δ+and red δ-) Note: Problems with italicized numbers
More informationREACTIONS OF AROMATIC COMPOUNDS
A STUDENT SHOULD BE ABLE TO: REACTIONS OF AROMATIC COMPOUNDS 1. Predict the product(s) of Electrophilic aromatic substitution (EAS): halogenation, sulfonation, nitration, Friedel- Crafts alkylation and
More informationCHAPTER 12. Substituted Benzene
CHAPTER 12 Substituted Benzene 12.1 Alkylbenzenes (Ar-R) Bezylic carbons: CH 3 CH 2 CH 3 CH(CH 3 ) 2 1 Reactions of Alkylbenzens 1. Free Radical Halogenation CH 2 CH 3 Br 2 hv Br CHCH 3 2 2- xidation R
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 informationElectrophilic Aromatic Substitution. Dr. Mishu Singh Department of chemistry Maharana Pratap Govt.P.G.College Hardoi
Electrophilic Aromatic Substitution Dr. Mishu Singh Department of chemistry Maharana Pratap Govt.P.G.College Hardoi 1 Recall the electophilic addition of HBr (or Br2) to alkenes H + nu cleophile H Br H
More informationChapter 16- Chemistry of Benzene: Electrophilic Aromatic Substitution
Chapter 16- Chemistry of Benzene: Electrophilic Aromatic Substitution Ashley Piekarski, Ph.D. Substitution Reactions of Benzene and Its Derivatives Benzene is aroma%c What does aromatic mean? Reac9ons
More informationI5 ELECTROPHILIC SUBSTITUTIONS OF
Section I Aromatic chemistry I5 ELECTPILIC SUBSTITUTINS F MN-SUBSTITUTED AMATIC INGS Key Notes ortho, meta and para substitution Substituent effect eaction profile Activating groups inductive o/p Deactivating
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 informationNBS, CCl 4 heat A B C D
1. What is(are) the expected product(s) of the following reaction? 2 C=CC( ) 2 NBS, CCl 4 heat A B C D 1) only B 2) only C 3) A and C 4) B and D 2. Which of the following is the 1,4-addition product in
More informationThere are two main electronic effects that substituents can exert:
Substituent Effects There are two main electronic effects that substituents can exert: RESONANCE effects are those that occur through the π system and can be represented by resonance structures. These
More information240 Chem. Aromatic Compounds. Chapter 6
240 Chem Aromatic Compounds Chapter 6 1 The expressing aromatic compounds came to mean benzene and derivatives of benzene. Structure of Benzene: Resonance Description C 6 H 6 1.It contains a six-membered
More informationClass XII: Chemistry Chapter 13: Amines Top concepts
Class XII: Chemistry Chapter 13: Amines Top concepts 1. Amines are regarded as derivatives of ammonia in which one, two or all three hydrogen atoms are replaced by alkyl or aryl group 2. Classification
More informationCHEM 242 REACTIONS OF ARENES: CHAP 12 ASSIGN ELECTROPHILIC AROMATIC SUBSTITUTION A B C D E
CHEM 242 REACTIONS OF ARENES: CHAP 12 ASSIGN ELECTROPHILIC AROMATIC SUBSTITUTION 1. Consider carefully the mechanism of the following electrophilic aromatic substitution reaction and indicate which of
More informationChem 263 Oct. 10, The strongest donating group determines where new substituents are introduced.
Chem 263 ct. 10, 2013 The strongest donating group determines where new substituents are introduced. N 2 N 3 2 S 4 + N 3 N 2 2 S 4 N 2 N 2 + 2 N N 2 N 3 2 S 4 N 2 2 N N 2 2,4,6-trinitrophenol picric acid
More information1. Which of the following reactions would have the smallest energy of activation?.
Name: Date: 1. Which of the following reactions would have the smallest energy of activation?. A) +. +. B) + +. C) +.. + D) +.. + E) +.. + 2. Which of the following reactions would have the smallest energy
More informationFrost Circles a Great Trick
Aromatics Frost Circles a Great Trick Inscribe a polygon of the same number of sides as the ring to be examined such that one of the vertices is at the bottom of the ring The relative energies of the MOs
More informationCHEMISTRY 263 HOME WORK
Lecture Topics: CHEMISTRY 263 HOME WORK Module7: Hydrogenation of Alkenes Hydrogenation - syn and anti- addition - hydrogenation of alkynes - synthesis of cis-alkenes -synthesis of trans-alkenes Text sections:
More informationChemistry 14D Winter 2010 Exam 2 Page 1
Chemistry 14D Winter 2010 Exam 2 Page 1 1. (2) Circle the best statement of Markovnikov s rule. (a) When X adds to an alkene, the hydrogen of X becomes bonded to the alkene carbon that bears the least
More informationChapter 16: Aromatic Compounds
Chamras Chemistry 106 Lecture otes xamination 2 Materials Chapter 16: Aromatic Compounds Benzene, the Most Commonly Known Aromatic Compound: The aromatic nature of benzene stabilizes it 36 kcal.mol 1.
More informationChapter 17 Aromati ti S u stit tit t u i tion Reactions
Chapter 17 Aromatic Substitution Reactions 1 17.1 Mechanism for Electricphilic Aromatic Substitution Arenium ion resonance stabilization 2 Example 1. Example 2. 3 Example 2. Mechanism of the nitration
More informationTOPIC 2. REACTIONS OF AROMATIC COMPOUNDS (Chapters 15, parts of 20, and 21)
L TPIC 2. REACTINS F ARMATIC CMPUNDS (Chapters 15, parts of 20, and 21) Add e.g. of SNAr, replace aniline example, turn BT into and example L TPIC 2. TC PAIN KILLERS BJECTIVES 1. Describe the reactions
More informationBENZENE & AROMATIC COMPOUNDS
BENZENE & AROMATIC COMPOUNDS Dr. Zainab M Almarhoon 2 Learning Objectives By the end of chapter four the students will: Understand the resonance description of structure of benzene Understand the hybridization
More information24. Electrophilic Aromatic Substitution
24. lectrophilic Aromatic Substitution A. Introduction Aromatic compounds are especially stable and despite having π-bonds do not react like typical alkenes. For example, the π-bond in 1-hexene is brominated
More informationLecture 27 Organic Chemistry 1
CHEM 232 rganic Chemistry I at Chicago Lecture 27 rganic Chemistry 1 Professor Duncan Wardrop April 20, 2010 1 Self Test Question Nitrosonium (not nitronium) cations can be generated by treating sodium
More information4 - BENZENE: AROMATICITY, CONJUGATION AND ASSOCIATED REACTIVITY
4 - BENZENE: AROMATICITY, CONJUGATION AND ASSOCIATED REACTIVITY During the early 1800's, a group of compounds of natural origin became collectively known as aromatic compounds. As several of these compounds
More information432 CHAPTER 19. Solutions H H H. Base H O H S O H - SO 3 O S O O O
432 CAPTER 19 Solutions 19.1. Base 19.2. S S - S 3 S S S CAPTER 19 433 19.3. D S D S 3 D D D D D 19.4. S - 2 nitronium ion 2 2 2 2 19.5. c) + 434 CAPTER 19 19.6. Al 3 Al 3 Al 3 Al 3 Al 3 Al 3 CAPTER 19
More informationChapter 17 Reactions of Aromatic Compounds
Chapter 17 Reactions of Aromatic Compounds Electrophilic Aromatic Substitution o General reaction - an electrophile replaces a hydrogen Electrons of pi system attack strong electrophile, generating resonancestabilized
More informationReactions. Reactions. Elimination. 2. Elimination Often competes with nucleophilic substitution. 2. Elimination Alkyl halide is treated with a base
eactions 1 eactions 2 2. limination Alkyl halide is treated with a base B: 2. limination ften competes with nucleophilic substitution LIMINATIN Nu: SUBSTITUTIN Nu Bimolecular B: limination B * * 3 Kinetics
More informationElectrophilic Aromatic Substitution
Electrophilic Aromatic Substitution Chemistry 391 10/14/02 Lecture 5 Diazonium Salts OH NH 2 NaNO 2 aq. HCl N N Cl H 2 O HCl Cl + H 3 O + Chemistry 391 10/16/02 Diazonium Salts The -N + 2 group of an arenediazonium
More informationTop concepts Chapter: Amines 1. Amines are regarded as derivatives of ammonia in which one, two or all three hydrogen atoms are replaced by alkyl or aryl group 2. Classification of amines: 3. Preparation
More informationChapter 23 Phenols CH. 23. Nomenclature. The OH group takes precedence as the parent phenol.
CH. 23 Chapter 23 Phenols Nomenclature The OH group takes precedence as the parent phenol. Carboxyl and acyl groups take precedence over the OH group. The OH group is a strong electron-donating group through
More informationThe now-banned diet drug fen-phen is a mixture of two synthetic substituted benzene: fenfluramine and phentermine.
The now-banned diet drug fen-phen is a mixture of two synthetic substituted benzene: fenfluramine and phentermine. Chemists have synthesized compounds with structures similar to adrenaline, producing amphetamine.
More informationCHEM 303 Organic Chemistry II Problem Set III Chapter 14 Answers
CHEM 303 rganic Chemistry II Problem Set III Chapter 14 Answers 1) Give the major products of each of the following reactions. If a mixture is expected, identify the major product. + H 3 CHC CHCH 3 H 2
More informationModule9. Nuclear Magnetic Resonance Spectroscopy Nuclear Magnetic Resonance (NMR) spectroscopy - Chemical shift - Integration of signal area
1 CHEMISTRY 263 HOME WORK Lecture Topics: Module7. Hydrogenation of Alkenes The Function of the Catalyst - Syn and anti- addition Hydrogenation of Alkynes - Syn- addition of hydrogen: Synthesis of cis-alkenes
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 informationChapter 09 Benzene and Its Derivatives
Chapter 09 Benzene and Its Derivatives Benzene First isolated in 1825 from whale oil by Michael Faraday Unsaturated hydrocarbon but did not have the typical reactivity of alkenes or alkynes. CM 240: Fall
More informationElimination. S N 2 in synthesis. S N 2 and E2. Kinetics. Mechanism bimolecular
bimolecular B: limination B * 1 Kinetics 2 ate determining step involves both reactants rate = k [base] [-] Second order kinetics 2 B + 2 = limination, 2 nd order 2 3 2 4 Zaitsev s ule In some cases a
More informationChem 263 Oct. 4, 2016
Chem 263 ct. 4, 2016 ow to determine position and reactivity: Examples The strongest donating group wins: 2 3 2 S 4 + 3 2 2 S 4 2 2 + 2 2 3 2 S 4 2 2 2 2,4,6-trinitrophenol picric acid This reactivity
More informationSeminar_3. 1. Substituded derivatives of benzene and their nomenclature
1. Substituded derivatives of benzene and their nomenclature 2. Reactions of arenes. Electrophilic aromatic substitutions 3. Activating substituents. Orientation in the aromatic ring Seminar_3 TEST - Aromatic
More informationBowman Chem 345 Lecture Notes by Topic. Electrophilic Aromatic Substitution (EAS):
lectrophilic Aromatic Substitution (AS): Aromatic rings have a tendency to be unreactive due to their inherent stability. However, aromatic rings can react given the right incentives. ne way, they can
More informationAlchohols, Phenols, Ethers
Aromatic ompounds Aromaticity lectrophilic aromatic subst. epetition cleophilic aromatic subst. (McM 7th ed, 16.7) Benzyne (McM 7th ed, 16.8) eduction of aromatics (McM 7th ed, 16.10) Alchohols, Phenols,
More informationCHEMISTRY. Module No and Title Module-, Electrophilic Aromatic Substitution: The ortho/para ipso attack, orientation in other ring systems.
Subject Chemistry Paper No and Title Paper-5, Organic Chemistry-II Module No and Title Module-, Electrophilic Aromatic Substitution: The ortho/para Module Tag CHE_P5_M29 TABLE OF CONTENTS 1. Learning Outcomes
More informationChapter 20 Amines-part 2
Reactions of Amines Lone pair on the nitrogen directs the chemistry of amines Chapter 20 Amines-part 2 The nitrogen lone pair can also make a carbon nucleophilic by resonance Amines can also activate carbons
More informationThere is basically one simple mechanism for all electrophilic aromatic substitutions:
Substitution Reactions of Aromatic Compounds Simple alkenes tend to undergo addition reactions: The elements of the reagent (HBr or Br2) are simply added to the starting material. This is called, unsurprisingly,
More informationChemistry 234 Chapter 16 Problem Set. 3) Predict the product and draw the active electrophile for each reaction shown below.
Chemistry 234 Chapter 16 Problem Set Electrophilic Aromatic Substitution 1) Predict the product and draw the mechanism for electrophile generation for each of the following reactions. (a) 2 Fe 3 (b) HN
More informationReactions of Aromatic Compounds. Aromatic compounds do not react like other alkenes. With an appropriate catalyst, however, benzene will react
Reactions of Aromatic Compounds Aromatic compounds do not react like other alkenes 2 Fe 3 2 Does not form A major part of the problem for this reaction is the product has lost all aromatic stabilization,
More informationChemistry 52 Exam #1. Name: 22 January This exam has six (6) questions, two cover pages, six pages, and 2 scratch pages.
Chemistry 52 Exam #1 Name: 22 January 2003 This exam has six (6) questions, two cover pages, six pages, and 2 scratch pages. Please check before beginning to make sure no questions are missing. 65 minutes
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 information5, Organic Chemistry-II (Reaction Mechanism-1)
Subject Chemistry Paper No and Title Module No and Title Module Tag 5, Organic Chemistry-II (Reaction Mechanism-1) 28, Arenium ion mechanism in electrophilic aromatic substitution, orientation and reactivity,
More information