Читать книгу Organic Mechanisms - Xiaoping Sun - Страница 4

1 Chapter 1FIGURE 1.1 Reaction profiles for a concerted S_N2 reaction (a) and a stepwise...FIGURE 1.2 The changes in concentrations of the reactant (X), intermediate (...FIGURE 1.3 The effects of enthalpy and entropy on reversibility of the chemi...FIGURE 1.4 Early transition state (a) and late transition state (b).FIGURE 1.5 The S_N2 reactions that proceed via (a) an early transition state ...FIGURE 1.6 The ρ constants for various reactions of substituted benzene...FIGURE 1.7 The shapes of the s and p orbitals in the three‐dimensional space...FIGURE 1.8 Formation of the hydrogen molecule (H₂) from two hydrogen (H) ato...FIGURE 1.9 Formation of the fluorine molecule (F₂) from two fluorine (F) ato...FIGURE 1.10 Formation of (a) the C=C π bond from two equivalent p orbitals a...FIGURE 1.11 Formation of conjugate π bonds from p orbitals in (a) the allyl ...FIGURE 1.12 Resonance stabilization of benzene.FIGURE 1.13 Possible resonance structures for the carbonyl (C=O) group.FIGURE 1.14 Resonance stabilization of the anolate anion.FIGURE 1.15 Possible resonance structures for (a) hydrogen chloride (HCl) an...FIGURE 1.16 Structure of different types of carbocations.FIGURE 1.17 (a) Overlap of a C─H bond of the methyl group in the ethyl catio...FIGURE 1.18 Reaction mechanism for acid‐catalyzed hydrolysis of the oxygen‐1...FIGURE 1.19 Energetics for C─H and C─D (deuterium) bonds.FIGURE 1.20 Reaction mechanism for nitration of benzene by acetyl nitrate.FIGURE 1.21 Acid–base catalysis for enzymatic reactions. (a) Uncatalyzed con...FIGURE 1.22 (a) Mechanism for the concerted reaction of H₂O and CO₂ giving H...FIGURE 1.23 Comparison of energetics for the concerted and the enzyme (carbo...FIGURE 1.24 Hydrophobic effects on organic reactions. (a) The intermolecular...

2 Chapter 2FIGURE 2.1 (a) Structure of and bonding in the methyl radical and (b) bondin...FIGURE 2.2 Molecular orbital model for the hyperconjugation effect in the et...FIGURE 2.3 Resonance stabilization for (a) the ethyl radical, (b) the isopro...FIGURE 2.4 Molecular orbitals in the allyl radical.FIGURE 2.5 Conjugation effect in the benzyl radical.FIGURE 2.6 Resonance stabilization for allyl (a) and benzyl radicals (b).FIGURE 2.7 Bond dissociation energies (BDEs) for HC≡C˙, C₆H₅˙, and H₂C=CH˙ r...FIGURE 2.8 Energy levels (BDE's—bond dissociation energies) for various radi...FIGURE 2.9 Mechanism for radical chlorination of methane.FIGURE 2.10 Nature of the transition states for the chain‐growth steps of ch...FIGURE 2.11 Reaction profiles for the chain‐growth steps of chlorination of ...FIGURE 2.12 Reaction profiles, transition states, and activation energies fo...FIGURE 2.13 (a) Overall mechanism for radical halogenation (substitution and...FIGURE 2.14 Thermal dissociation of (PhCOO)₂ giving the Ph˙ radical.FIGURE 2.15 Mechanism for (PhCOO)₂ initiated autoxidation of cumene (isoprop...FIGURE 2.16 The alkane C─H bond activation by transition metal complex...FIGURE 2.17 The alkane C─H bond activation by various transition metal...FIGURE 2.18 Mechanism for the methane C─H bond activation by mercury(I...FIGURE 2.19 Structure of dichloro(η‐2‐{2,2′‐bipyrimidyl})platinum(II), denot...FIGURE 2.20 Mechanism for the (bpym)PtCl₂ catalyzed functionalization of met...FIGURE 2.21 The proposed transition states for the hydrogen abstraction of t...FIGURE 2.22 Reactions of alkanes with elemental sulfur in triflic acid.FIGURE 2.23 Mechanism for the triflic acid catalyzed alkane C─H bond a...FIGURE 2.24 The protonated nitronium NO₂H²⁺ dication and its reaction with m...FIGURE 2.25 Nitration of adamantane via a three‐center, two‐electron bond ca...FIGURE 2.26 Reactions of nitronium hexafluorophosphate with (a) ethane, (b) ...FIGURE 2.27 Cytochrome P‐450 catalyzed alkane C─H bond oxidative funct...FIGURE 2.28 Structure of active site of methane monooxygenase (MMO) and mech...

3 Chapter 3FIGURE 3.1 Mechanism and regioselectivity for electrophilic addition of hydr...FIGURE 3.2 Reaction profiles for electrophilic addition of hydrogen chloride...FIGURE 3.3 Regioselectivity for electrophilic addition of hydrogen bromide t...FIGURE 3.4 Mechanism and stereochemistry for electrophilic addition of hydro...FIGURE 3.5 Mechanism, regiochemistry, and stereochemistry for electrophilic ...FIGURE 3.6 Stereoselectivity of electrophilic addition of hydrogen iodide to...FIGURE 3.7 The acid‐catalyzed hydration of various alkenes.FIGURE 3.8 Mechanism for the acid‐catalyzed hydration of 1‐methoxycyclohexen...FIGURE 3.9 Structure of mercury(II) acetate.FIGURE 3.10 Mechanism and regioselectivity for mercury(II) acetate catalyzed...FIGURE 3.11 The acid‐catalyzed electrophilic addition of alcohols to various...FIGURE 3.12 Mechanism for toluenesulfonic acid catalyzed electrophilic addit...FIGURE 3.13 Aluminum chloride catalyzed addition of benzene to cyclohexene....FIGURE 3.14 Acid catalyzed reaction of 2‐methylpropene with isobutane effect...FIGURE 3.15 The AlCl₃‐catalyzed electrophilic addition of deuterated PhCD₂Cl...FIGURE 3.16 Electrophilic addition of hydrogen chloride to 1,3‐butadiene. (a...FIGURE 3.17 Radical initiated Non‐Markovnikov addition of hydrogen bromide t...FIGURE 3.18 Structure of and bonding in diborane and borane. The three‐cente...FIGURE 3.19 Mechanism for hydroboration of alkenes: Concerted, non‐Markovnik...FIGURE 3.20 Mechanism, regiochemistry, and stereochemistry for hydroboration...FIGURE 3.21 Synthesis of 9‐borabicyclo[3.3.1]nonane (9‐BBN).FIGURE 3.22 Hydroboration of a‐pinene by diborane (via BH₃) in THF.FIGURE 3.23 Comparison of regioselectivity for alkene hydroborations effecte...FIGURE 3.24 Stereoselectivity for hydroboration reactions of (R)‐ and (S)‐3‐...FIGURE 3.25 Mechanism for transition‐metal catalyzed heterogeneous hydrogena...FIGURE 3.26 The MO diagram for the formation of the H─M─H bonds from H₂ and ...FIGURE 3.27 Palladium catalyzed hydrogenation of 2,3‐diphenyl‐2‐butenes in (FIGURE 3.28 A hypothesized hydrogenated fat (saturated) made by transition‐m...FIGURE 3.29 Mechanism and transition states for halogenation of alkene in di...FIGURE 3.30 Mechanism and stereochemistry for bromination of cyclohexene in ...FIGURE 3.31 Regioselectivity and stereoselectivity for bromination of (Z)‐1‐...FIGURE 3.32 Bromination of (R)‐4‐tert‐butylcyclohexene giving stereospecific...FIGURE 3.33 Reactions of cyclohexene with elemental bromine in water (a) and...FIGURE 3.34 Regiochemistry and stereochemistry for reactions of 1‐methylcycl...

4 Chapter 4FIGURE 4.1 Prototype for electrophilic cycloaddition of an alkene forming a ...FIGURE 4.2 Epoxidation of an alkene by a percarboxylic acid following a conc...FIGURE 4.3 Examples of alkene epxidation reactions.FIGURE 4.4 Mechanism for cycloaddition of dichlorocarbene (CCl₂) to an alken...FIGURE 4.5 Stereochemistry for cycloaddition of dichlorocarbene (CCl₂) to al...FIGURE 4.6 Removal of chloro groups (defunctionalization) from 1,1‐dicloropr...FIGURE 4.7 Stepwise radical mechanism for cycloaddition of the triplet diphe...FIGURE 4.8 Mechanism and stereochemistry for cycloadditions of a carbenoid t...FIGURE 4.9 π molecular orbital diagram of ethylene.FIGURE 4.10 Possible frontier molecular orbital (FMO) interactions between t...FIGURE 4.11 HOMO–LUMO electronic transition in ethylene.FIGURE 4.12 Possible frontier molecular orbital (FMO) interactions between a...FIGURE 4.13 Mechanism and stereochemistry for photochemical cycloaddition of...FIGURE 4.14 Mechanism and stereochemistry for photochemical cycloaddition of...FIGURE 4.15 Frontier molecular orbital (FMO) interactions involved in therma...FIGURE 4.16 Effect of an electron‐withdrawing group on the energy level of L...FIGURE 4.17 Examples of Diels–Alder reactions of 1,3‐butadiene derivatives w...FIGURE 4.18 Regiochemistry for Diels–Alder reaction.FIGURE 4.19 Diels–Alder reaction of 1,3‐cyclopentdiene with ethylene giving ...FIGURE 4.20 Diels–Alder reactions of the C=N containing t‐butyl 2‐azidoacryl...FIGURE 4.21 Diels–Alder reactions of 1,3‐cyclopentadiene with 2,3‐dicyano‐p‐...FIGURE 4.22 Diels–Alder reactions for larger cyclic systems.FIGURE 4.23 Regioselectivity and stereoselectivity for Diels–Alder reactions...FIGURE 4.24 Synthesis of tofogliflozin by a 6π intramolecular diene‐yne Diel...FIGURE 4.25 Frontier molecular orbital (FMO) interactions involved in therma...FIGURE 4.26 Overall mechanism for oxidation of an alkene to two carbonyl gro...FIGURE 4.27 Cycloaddition reaction of an alkene to diazomethane.FIGURE 4.28 (a) The in‐plane sideway overlaps of p orbitals in two perpendic...FIGURE 4.29 Thermally symmetry‐allowed cycloadditions of the dithionitronium...FIGURE 4.30 Mechanism for cycloaddition of an alkene to an alkene‐NS₂⁺ cyclo...FIGURE 4.31 Stereochemistry of cycloadditions of alkenes to alkene‐NS₂⁺ cycl...FIGURE 4.32 Cycloaddition of [S=N=S]⁺ to 2,3‐dimethyl‐2‐butene.FIGURE 4.33 Thermally symmetry‐allowed cycloadditions of [S=N=S]⁺ to alkynes...FIGURE 4.34 Mechanism for intramolecular ring‐closure (cyclization) of 1,3,5...FIGURE 4.35 Mechanism for the Cope rearrangement of deuterium isotope‐labele...FIGURE 4.36 Photochemical ring‐closure of 1,3‐butadiene to cyclobutene.FIGURE 4.37 The 4π‐cycloaddition between the N=N bonds. (a) Pathway for a re...FIGURE 4.38 The 4π‐cycloaddition of C₆₀ with 2,5‐dimethyl‐2,4‐hexadiene.FIGURE 4.39 The energetics of FMOs for the 4 π 1,3‐cyclopentadiene and 2 π e...FIGURE 4.40 Comparison of the 6 π Diels–Alder cycloadditions of a 1,3‐dipole...FIGURE 4.41 The energetics of FMOs for a 4 π 1,3‐dipole and the 2 π styrene ...FIGURE 4.42 The FMO interactions for the cycloaddition reaction of quadricyc...FIGURE 4.43 Chemical synthesis of Vitamin D₂ via the ring‐opening process of...FIGURE 4.44 The ribosome‐catalyzed formation of the peptide bond (C–N) in bi...

5 Chapter 5FIGURE 5.1 General mechanism for the electrophilic aromatic substitution (EA...FIGURE 5.2 Formation of a stable arenium (σ‐complex) between hexamethylbenze...FIGURE 5.3 The full mechanism for the charge‐transfer aromatic nitration.FIGURE 5.4 Mechanism for the electrophilic substitution reaction of benzene ...FIGURE 5.5 Formation of a stable arenium (σ‐complex) between hexamethylbenze...FIGURE 5.6 Possible mechanism for the AlCl₃‐catalyzed electrophilic substitu...FIGURE 5.7 Possible mechanism for the AlCl₃‐catalyzed electrophilic aromatic...FIGURE 5.8 AlCl₃‐catalyzed electrophilic aromatic substitution of p‐toluenes...FIGURE 5.9 (a) Reaction of antimony pentachloride (SbCl₅) with hexamethylben...FIGURE 5.10 Unexpected ring‐opening process in the AlCl₃‐catalyzed Friedel–C...FIGURE 5.11 FeCl₃‐catalyzed EAS reactions of arenes with aldehydes.FIGURE 5.12 FeCl₃‐catalyzed intramolecular EAS reactions of benzyl alcohol d...FIGURE 5.13 FeCl₃‐catalyzed regioselective EAS reactions of alkenes and poss...FIGURE 5.14 Mechanism for the FeCl₃‐catalyzed reaction of chlorobenzene with...FIGURE 5.15 The d_π–pπ* back bonding between Fe(III) and the S=O bond in...FIGURE 5.16 Mechanism for AlCl₃‐catalyzed Friedel–Crafts reaction of benzene...FIGURE 5.17 Mechanism for AlCl₃‐catalyzed Friedel–Crafts reaction of benzene...FIGURE 5.18 Mechanism for AlCl₃‐catalyzed Friedel–Crafts reaction of benzene...FIGURE 5.19 Mechanism for acid‐catalyzed electrophilic substitution reaction...FIGURE 5.20 Mechanism for acid‐catalyzed electrophilic substitution reaction...FIGURE 5.21 Mechanism for an intramolecular electrophilic aromatic substitut...FIGURE 5.22 Mechanism for an electrophilic aromatic substitution reaction of...FIGURE 5.23 Mechanism for an intramolecular electrophilic aromatic substitut...FIGURE 5.24 Simplified and more subtle models for the charge distribution in...FIGURE 5.25 Common electron‐donating and electron‐withdrawing groups (EDG's ...FIGURE 5.26 The intermediate ortho‐, meta‐, and para‐arenium ions which bear...FIGURE 5.27 Chlorination of alkylbenzenes: Directing effects of different al...FIGURE 5.28 Reaction of phenol with bromine: Para‐directing effect of the hy...FIGURE 5.29 The intermediate ortho‐, meta‐, and para‐arenium ions which bear...FIGURE 5.30 Mechanism for proton‐catalyzed isomerization of 1,2,4‐tri(t‐buty...FIGURE 5.31 Mechanism for proton‐catalyzed dealkylation of 2,4‐dichlorocumen...FIGURE 5.32 Mechanism for acid‐catalyzed isomerization of α‐naphthalenesulfo...FIGURE 5.33 Metals (magnesium and lithium) facilitated electrophilic aromati...FIGURE 5.34 Metal directing groups (MDG's) facilitated lithiumation of arene...FIGURE 5.35 Reactions of substituted arenes with ^sBuLi followed by substitut...FIGURE 5.36 ortho‐Metal directing group facilitated lithiumation and subsequ...FIGURE 5.37 Nucleophilic aromatic substitution (NAS) of a halobenzene via th...FIGURE 5.38 Mechanism for nucleophilic substitution of the carbon‐14 isotope...FIGURE 5.39 Nucleophilic substitution reaction of o‐chlorotoluene with hydro...FIGURE 5.40 Nucleophilic substitution reactions of halobenzenes with cyanide...FIGURE 5.41 Nucleophilic substitution reactions of aryldiazonium (Ar–⁺N=N) f...FIGURE 5.42 Reaction of 2‐bromobenzoic acid with benzyl nitrile (C₆H₅CH₂CN) ...FIGURE 5.43 Nucleophilic aromatic substitution via the Meisenheimer complex....FIGURE 5.44 Reaction of 2,4‐dinitrochlorobenzene with hydrazine giving 2,4‐d...FIGURE 5.45 Nucleophilic substitution of 2,4‐difluoronitrobenzene with liqui...FIGURE 5.46 The azocoupling reaction between 1,3‐dinitrobenzene and aryldiaz...FIGURE 5.47 Structures of Combretastatin A‐4 (CA4) and modified analogues.FIGURE 5.48 Synthesis of the diaryl sulfide analogue of CA4 by nucleophilic ...FIGURE 5.49 The aryl‐sulfoxide‐containing nitrogen mustard and its in vivo r...FIGURE 5.50 Synthesis of a biomedically active aryl‐sulfoxide‐containing pol...FIGURE 5.51 Chemical synthesis of the inflammatory ibuprofen and the reactio...

6 Chapter 6FIGURE 6.1 Super and very good leaving groups.FIGURE 6.2 Possible resonance structures for phenoxide and acetate, accounti...FIGURE 6.3 Reaction of sodium azide and (2S)‐2‐triflyloxyester in CH₃CN (an ...FIGURE 6.4 Reaction of trans‐1‐bromo‐4‐methylcyclohexane and sodium hydrogen...FIGURE 6.5 Effect of steric hindrance on relative rate constants for the S_N2...FIGURE 6.6 Effect of steric hindrance on relative rate constants for the S_N2...FIGURE 6.7 Destabilization of the S_N2 transition states by steric interactio...FIGURE 6.8 The S_N2 reactions of hydroxide and water with bromomethane: compa...FIGURE 6.9 Energy profiles for the S_N2 reactions in (1) a more polar protic ...FIGURE 6.10 Stabilization of the S_N2 transition state by an unsaturated grou...FIGURE 6.11 (a) Molecular orbitals (MOs) in CH₃X (X = Cl, Br, or I) which ar...FIGURE 6.12 (a) Maximum overlap of a nucleophile orbital with the 2p_z‐based ...FIGURE 6.13 (a) Molecular orbitals (MOs) in RCH₂X (X = Cl, Br, or I; R = alk...FIGURE 6.14 Occupied bonding molecular orbitals (MOs) in CH₂Cl₂ which are fo...FIGURE 6.15 Reaction profile for the S_N1 mechanism.FIGURE 6.16 The S_N1 reactions of 2‐chloro‐2‐methylpropane in protic solvents...FIGURE 6.17 The S_N1 rate constants for hydrolysis of various bromoalkanes....FIGURE 6.18 Energy profiles for rate‐determining steps of the S_N1 reactions ...FIGURE 6.19 Reaction profiles for both S_N1 and S_N2 reactions of RCl, RBr, an...FIGURE 6.20 Mechanism and product development of the S_N1 reaction.FIGURE 6.21 Stereoselectivity of the S_N1 reactions.FIGURE 6.22 The S_N1 and S_N2 reactions of (R)‐2‐bromobutane performed in diff...FIGURE 6.23 The S_N1 (a) and S_N2 (b) hydrolysis of benzyl chloride.FIGURE 6.24 The S_N2 reaction of a Grignard reagent with ethylene oxide.FIGURE 6.25 (a) Regiospecific S_N2 reaction of phenylmagnesium bromide with a...FIGURE 6.26 The S_N2 reactions of alkyne anions with primary haloalkanes.FIGURE 6.27 The Gabriel synthesis.FIGURE 6.28 The S_N2 reaction of triphenylphosphine (Ph₃P) with a primary hal...FIGURE 6.29 Neighboring group‐assisted nucleophilic substitution reaction of...FIGURE 6.30 Neighboring group‐assisted hydrolysis of mustard gas.FIGURE 6.31 Mechanism and stereochemistry for neighboring group‐assisted nuc...FIGURE 6.32 Neighboring group assisted nucleophilic substitution of trans‐2‐...FIGURE 6.33 Mechanisms for the alcohol nucleophilic substitution reactions c...FIGURE 6.34 The S_N2 mechanism for alkylation of guanine in a DNA molecule by...FIGURE 6.35 The intrastrand crosslink between nitrogen bases of a DNA chain ...FIGURE 6.36 Cyclic structures of α‐ and β‐D‐glucose and α‐ and β‐glycoside. ...FIGURE 6.37 Mechanisms for (a) retaining β‐glucosidases; and (b) inverting β...FIGURE 6.38 Mechanism for hydrolysis of bacteria walls polysaccharide by lys...FIGURE 6.39 Biosynthesis of geraniol through S_N1 reactions.FIGURE 6.40 Biosynthesis of epinephrine from norepinephrine and S‐adenosylme...FIGURE 6.41 An enzyme‐catalyzed S_N2 reaction of an haloalkane.

7 Chapter 7FIGURE 7.1 The E2 reaction mechanism.FIGURE 7.2 The E2 reaction of 2‐bromo‐2‐methylpentane induced by different b...FIGURE 7.3 Steric hindrance of t‐butoxide on the E2 reaction of 2‐bromo‐2‐me...FIGURE 7.4 Reactions of cis‐ and trans‐4‐(t‐butyl)cyclohexyl tosylate with tFIGURE 7.5 The E2 reactions of trans‐ and cis‐1‐bromo‐2‐methylcyclohexane in...FIGURE 7.6 The E2 reactions of 1‐bromo‐1‐methylcyclohexane induced by differ...FIGURE 7.7 Stereochemistry for the E2 reactions of different stereoisomers o...FIGURE 7.8 (a) Anti‐coplanar arrangement of the C_α─X and C_β─H bond...FIGURE 7.9 Correlations of frontier molecular orbitals for the E2 reaction o...FIGURE 7.10 Syn‐coplanar arrangement of the C_α─X and C_β─H bonds in...FIGURE 7.11 (a) Chair‐conformations of a halocyclohexane (X = Cl, Br, or I)....FIGURE 7.12 Basicity versus nucleophilicity for various species.FIGURE 7.13 E2 and S_N2 reactions for an epoxide.FIGURE 7.14 Competition between E2 and S_N2 reactions.FIGURE 7.15 Ethoxide (⁻OEt) induced E2 reactions versus S_N2 reactions ...FIGURE 7.16 The E1 reaction mechanism.FIGURE 7.17 The acid‐catalyzed dehydration of (a) 2‐methyl‐2‐butanol and (b)...FIGURE 7.18 Bell–Evans–Polanyi principle: dependence of activation energy on...FIGURE 7.19 Reaction profiles for E1 dehydrations of 2‐methyl‐2‐butanol and ...FIGURE 7.20 The acid‐catalyzed E1 dehydration of 1‐cyclohexylethanol.FIGURE 7.21 Reaction profiles for E1 reactions of haloalkanes.FIGURE 7.22 Mechanism for the E1 elimination of a tertiary butyl ether.FIGURE 7.23 Mechanism for the unimolecular syn‐elimination of an ester.FIGURE 7.24 Examples for unimolecular syn‐eliminations of esters: (a) ethyl ...FIGURE 7.25 Silyloxide elimination: (a) Base‐induced syn‐elimination and (b)...FIGURE 7.26 Mechanism for zinc‐induced anti‐eliminations of vicinal dihalide...FIGURE 7.27 Mechanism for reductive anti‐elimination of vicinal alkane dihal...FIGURE 7.28 Reductive elimination of a chlorinated ethylene by metallic zinc...FIGURE 7.29 (a) Molecular orbitals (MOs) in CHCl₃ which are formed by linear...FIGURE 7.30 Molecular orbital diagram for the base induced α‐elimination of ...FIGURE 7.31 Energy profile for a base‐initiated E1cb reaction.FIGURE 7.32 Elimination of NMe₃ from a quaternary amine, which possesses an ...FIGURE 7.33 The FAD‐facilitated E1cb‐like elimination: a biological eliminat...FIGURE 7.34 An enzyme‐catalyzed E1cb elimination involved in biosynthesis of...FIGURE 7.35 The E1 mechanism for biosynthesis of limonene from linalyl dipho...

8 Chapter 8FIGURE 8.1 (a) Addition of a strong nucleophile to a ketone or aldehyde; (b)...FIGURE 8.2 Mechanism for the hydroxide base catalyzed hydrolysis of ester (e...FIGURE 8.3 Acid and base catalyzed hydration of ketone or aldehyde.FIGURE 8.4 Mechanism for oxygen exchange between acetone and water.FIGURE 8.5 Mechanism for acid catalyzed nucleophilic addition of methanol to...FIGURE 8.6 Acid catalyzed nucleophilic addition reactions of various alcohol...FIGURE 8.7 Acid catalyzed reaction of an ester‐aldehyde with methanol, follo...FIGURE 8.8 The intramolecular nucleophilic addition of 6‐hydroxyl‐2‐heptanon...FIGURE 8.9 Cyclic structures and mutarotation of D‐glucose: the intramolecul...FIGURE 8.10 Cyclic structures and mutarotation of D‐fructose: the intramolec...FIGURE 8.11 Formations of cyclic structures of five‐carbon and six‐carbon su...FIGURE 8.12 Mechanism for acid catalyzed nucleophilic addition of an amine t...FIGURE 8.13 Reactions of a ketone or aldehyde to various compounds containin...FIGURE 8.14 Mechanism for reaction of a secondary amine with a ketone (cyclo...FIGURE 8.15 The enzymatic mechanism for conversion of fructose‐1,6‐bisphosph...FIGURE 8.16 Mechanism for nucleophilic addition of borohydride to a ketone o...FIGURE 8.17 Mechanism for nucleophilic addition of aluminum hydride to a ket...FIGURE 8.18 Structures of NAD(P)⁺ and NAD(P)H (biological hydride donor).FIGURE 8.19 Mechanism for lactate dehydrogenase (LDH) catalyzed homolactic f...FIGURE 8.20 Structures of FAD and FADH₂ (biological hydride donor).FIGURE 8.21 Reaction of a carboxylic acid with thionyl chloride.FIGURE 8.22 (a) Fischer esterification and reaction mechanism; and (b) react...FIGURE 8.23 Formation of a lactone by the entropy‐driven intramolecular este...FIGURE 8.24 (a) Structure of p‐dodecylbenzenesulfonic acid (DBSA); and (b) t...FIGURE 8.25 The p‐dodecylbenzenesulfonic acid (DBSA) catalyzed esterificatio...FIGURE 8.26 Formation of a cyclic carboxylic anhydride (succinic anhydride) ...FIGURE 8.27 Nucleophilic addition of ⁿBuLi to a carboxylic acid.FIGURE 8.28 Nucleophilic acyl substitution reactions of an alcohol with an a...FIGURE 8.29 Mechanism for acid catalyzed esterification reaction of salicyli...FIGURE 8.30 Nucleophilic acyl substitution reactions of a primary amine with...FIGURE 8.31 Nucleophilic acyl substitution reaction of a primary amine with ...FIGURE 8.32 Mechanisms for acid and base catalyzed transesterification.FIGURE 8.33 Synthesis of biodiesel from corn oil.FIGURE 8.34 Mechanism for the formation of methyl ester of fatty acids (biod...FIGURE 8.35 The hydrolytic peptide bond cleavage in proteins catalyzed by se...FIGURE 8.36 The catalytic mechanism for trypsin (a serine protease).FIGURE 8.37 The reaction profile for the trypsin catalyzed hydrolytic cleava...FIGURE 8.38 Lipase catalyzed hydrolysis of triacylglycerol to fatty acids.FIGURE 8.39 Enzymatic mechanism for hydrolysis of triacylglycerol catalyzed ...FIGURE 8.40 Reductions of (a) acyl chlorides, carboxylic anhydrides, and est...FIGURE 8.41 Mechanism for reduction of an amide to an amine by lithium alumi...FIGURE 8.42 Mechanism for cyanide catalyzed nucleophilic addition of benzald...

9 Chapter 9FIGURE 9.1 Molecular orbitals formed due to the hyperconjugation between the...FIGURE 9.2 Formation of the enolate from a carbonyl compound and its equilib...FIGURE 9.3 Crystal structure of lithium enolate of 2,2‐dimethyl‐2‐butanone....FIGURE 9.4 Regiochemistry for deprotonation of unsymmetrical ketones by LDA ...FIGURE 9.5 Occupied molecular orbitals for the three‐center, four‐electron b...FIGURE 9.6 Alkylation of carbonyl compounds via enolates and primary alkyl h...FIGURE 9.7 Alkylation of carbonyl compounds via enolates and primary alkyl d...FIGURE 9.8 Alkylation of (a) an aldehyde and (b) a ketone via N,N‐dimethylhy...FIGURE 9.9 Alkylation of a ketone via a secondary amine.FIGURE 9.10 The general mechanism for an aldol reaction of an aldehyde or ke...FIGURE 9.11 The crossed aldol condensation reactions between (a) benzaldehyd...FIGURE 9.12 Transition states and stereochemistry for the aldol reaction of ...FIGURE 9.13 The intramolecular aldol condensations to form cyclic α,β‐unsatu...FIGURE 9.14 The aldol reaction of benzaldehyde with acetic anhydride catalyz...FIGURE 9.15 The acid catalyzed aldol condensation of acetone via an enol.FIGURE 9.16 Mechanism for the (S)‐proline catalyzed enantiomerically specifi...FIGURE 9.17 Mechanism for the (S)‐proline catalyzed enantiomerically specifi...FIGURE 9.18 Mechanism for the (S)‐proline catalyzed diastereoselective aldol...FIGURE 9.19 Diastereoseletive aldol reactions of (a) (Z)‐ and (b) (E)‐enolat...FIGURE 9.20 (a) Nucleophilic 1,2‐ and 1,4‐additions to an α,β‐unsaturated ca...FIGURE 9.21 (a) Resonance structures and (b) the occupied molecular orbitals...FIGURE 9.22 Mechanism for the Robinson annulations.FIGURE 9.23 Darzens condensation: Reaction and mechanism.FIGURE 9.24 Mechanism for Claisen condensation of an ester.FIGURE 9.25 Alkylation of a β‐ketoester via the S_N2 reaction of the enolate ...FIGURE 9.26 Alkylation of a β‐ketoester via the S_N2 reaction of the enolate ...FIGURE 9.27 Alkylation of a diester by reaction of the enolate with 1,4‐dibr...FIGURE 9.28 The intramolecular Claisen condensation of a 1,7‐diester and sub...FIGURE 9.29 (a) The alkoxide base catalyzed crossed Claisen condensation giv...FIGURE 9.30 Structure of acetyl‐coenzyme A.FIGURE 9.31 The enzymatic mechanism for synthesis of citrate, the first step...FIGURE 9.32 Mechanism for thiolase catalyzed Claisen condensation of acetyl‐...

10 Chapter 10FIGURE 10.1 Major types of rearrangements identified in organic reactions.FIGURE 10.2 The 1,2‐shift in a general carbocation.FIGURE 10.3 The carbocation 1,2‐shifts involved in SbF₅ catalyzed isomerizat...FIGURE 10.4 The carbocation rearrangements involved in (a) electrophilic add...FIGURE 10.5 The ring expansions involved in (a) nucleophilic substitution re...FIGURE 10.6 (a) Pinacol rearrangement, (b) acid catalyzed ring‐expansion and...FIGURE 10.7 The concerted cascade carbocation 1,2‐rearrangements in a bioche...FIGURE 10.8 The 1,2‐shift in an epoxide.FIGURE 10.9 Anion‐initiated 1,2‐shifts: (a) Isomerization of a 1,2‐diketone ...FIGURE 10.10 The general mechanism for neighboring leaving group facilitated...FIGURE 10.11 Mechanism of Beckmann rearrangement, a 1,2‐shift in a nitrilium...FIGURE 10.12 Mechanism of Beckmann rearrangement involved in transformation ...FIGURE 10.13 Mechanism of Hofmann rearrangement involved in transformation o...FIGURE 10.14 Mechanism of Hofmann rearrangement for a cyclic amide.FIGURE 10.15 Mechanism of Baeyer–Villiger oxidation (rearrangement): Oxidati...FIGURE 10.16 Mechanism for Baeyer–Villiger oxidation of cyclopentanone to a ...FIGURE 10.17 The regioselectivity for the Baeyer–Villiger oxidation of unsym...FIGURE 10.18 The regio‐ and stereo‐chemistry for the Baeyer–Villiger oxidati...FIGURE 10.19 Mechanism for the acid catalyzed carbon–oxygen rearrangement of...FIGURE 10.20 Electron‐pair facilitated 1,2‐rearrangement in carbene.FIGURE 10.21 Synthesis of carbene from a ketone and stereoelectronic control...FIGURE 10.22 Stereoselective 1,2‐rearrangement of a carbene.FIGURE 10.23 Cyclization of a carbene via a 1,3‐shift.FIGURE 10.24 Photochemical 1,2‐rearrangement of an alkene to a carbene, the ...FIGURE 10.25 Claisen rearrangement (a), an analogous process to the Cope rea...FIGURE 10.26 Claisen rearrangement of a cyclic allyl vinyl ether to a γ,δ‐en...FIGURE 10.27 Claisen rearrangement of trans‐butenyl phenyl ether to an o‐all...FIGURE 10.28 A strong base induced Claisen rearrangement of an allyl ester t...FIGURE 10.29 The Claisen rearrangement of chorismate to prephenate in water ...FIGURE 10.30 The Claisen rearrangement of (a) 6‐β‐glycosylallyl vinyl ether ...FIGURE 10.31 The Claisen rearrangement of a naphthyl ether in water.FIGURE 10.32 Mechanism for the photochemical isomerization of trans‐2‐stilbe...FIGURE 10.33 The photochemical rearrangement of cis‐11‐retinol to its trans‐...FIGURE 10.34 Synthesis of (a) the 6π 5‐organo‐1,3,2,4‐dithiadiazolium hetero...FIGURE 10.35 The photochemical rearrangement of 5‐organo‐1,3,2,4‐dithiadiazo...FIGURE 10.36 Mechanism for the concerted photochemically symmetry allowed bi...