Orgo 2 Exam 2

hydrogen-cyanide conjugate addition

1,2 addition reversible; 1,4 addition more stable

conjugate hydration (ether formation)

water, alcohols, and amines

Organometallic Reagents

Intramolecular aldol condensation

Ketons (aldol condensation)

Crossed aldol condensation (one aldehyde not enolizable)

Aldol condensation

Hydrogenation (a,b unsat. aldehydes and ketones reactions)

Addition of Halogen (a,b unsat. aldehydes and ketones reactions)

Condensations with Amine Derivatives (a,b unsat. aldehydes and ketones reactions)

Hydrogen Cyanide Addition (conjugate additions to a,b unsat. aldehydes and ketones)

Water, alcohols, amines (conjugate additions to a,b unsat. aldehydes and ketones)

Organometallic Reagents (conjugate additions to a,b unsat. aldehydes and ketones)

Cuprate additions, enolate alkylations (conjugate additions to a,b unsat. aldehydes and ketones)

Michael Addition (conjugate additions to a,b unsat. aldehydes and ketones)

Robinson Annulation (conjugate additions to a,b unsat. aldehydes and ketones)

alpha hydrogens

acidic (due to e- withdrawing of fg and resulting enolate ion is resonance stabilized)

Unsymmetrical ketones generate ___ with LDA at low temps

less substituted kinetic enolate

Unsymmetrical ketones generate ___ with a weak base at high temps under equilibrating cond.

more substituted thermodynamic enolate

haloalkanes prefer

alpha-alkylation

protonation of oxygen leads to

enols

enamines

neutral analogs of enolates

a-halogenation maybe be

acid or base catalyzed

acid catalyzed a-halogenation

the enol is halogenated by attack at the double bond and the enolization is slowed down by the halogen substituent

base catalyzed a-halogenation

the enolate is attacked at the carbon and the enolate formation is accelerated by halogens introduced

enolates are…

electrophilic and reversibly attack the carbonyl carbon of an aldehyde or ketone in aldol condensation

attack the b-carbon of a a,b-unsat. carbonyl compound in michael addition

acidity of carboxylic acids

basicity of carboxylic acids

RCH2OH—?—→RCOOH (oxidization)

oxidizing agents: aqueous CrO3, KMnO4, HNO3

RCHO—?—→RCOOH (oxidization)

oxidizing agents: CrO3, KMnO4, Ag+, H2O2, HNO3

RMgX+CO2 —?→ RCOO- +MgX —?→ RCOOH (carbonation of organometallic reagents)

1. THF

2. H+,H2O

RLi+CO2 —?→ RCOO- +Li —?→ RCOOH (carbonation of organometallic reagents)

1. THF

2. H+,H2O

RCN—?→ RCOOH + NH3(acid catalyzed)/NH4+(base catalyzed) (hydrolysis of nitriles)

H20,heat,H+,H+(acid catalyzed)/OH-(base catalyzed)

Nucleophilic attack at the carbonyl group (base catalyzed addition-elimination)(reactions of carbox. acid)

Nucleophilic attack at the carbonyl group (acid catalyzed addition-elimination)(reactions of carbox. acid)

acyl halides (deriv. of carbox. acids) (SOCl2)

acyl halides (deriv. of carbox. acids) (PBr3)

Carboxylic Anhydrides

Cyclic anhydrides

carboxylic amides

imides

cyclic amides (lactams)

RCOOH —?→ RCH2OH (reduction with lithium aluminum hydride)

1. LiAlH4,(CH3CH2)2O

2. H+,H2O

Bromination: Hell-Volhard-Zelinsky Reaction

.

.

carboxylic acids

alkanoic acids

dicarboxylic acids

alkanedioic acids

cyclic and aromatic systems involving carboxylic acids

cycloalkanecarboxylic and benzoic acids

carboxy groups

trigonal planer

EXCEPT in dilute solutions and then it forms dimers by h-bonding

carbonyl group in carboxylic acids undergo nucleophilic displacement via ___

addition-elimination pathways

addition of nucleophile ______ that decomposes by elimination of the hydroxy group to _____

1. gives an unstable tetrahedral intermediate

2. give a carboxylic acid derivative

LiAlH4 is strong enough to add to the carbonyl group of ____ which allows the reduction of carboxylic acids to _____

1. carboxylate ions

2. primary alcohols

Order of Reactivity of Carboxylic Acid Derivatives

Basicity of the Carbonyl Oxygen

Enolate Formation

Water (reactions of acyl halides)

Carboxylic acids (reactions of acyl halides)

alcohols (reactions of acyl halides)

Amines (reactions of acyl halides)

Cuprate Reagents (reactions of acyl halides)

Hydrides (reactions of acyl halides)

Water (reactions of carboxylic acid anhydrides)

Alcohols (reactions of carboxylic acid anhydrides)

Amines (reactions of carboxylic acid anhydrides)

Water-acid catalyzed (Ester Hydrolysis) (Reactions of Esters)

Water-base catalyzed (Ester Hydrolysis) (Reactions of Esters)

Alcohols (Transesterification) (Reactions of Esters)

Amines (Reactions of Esters)

Organometallic Reagents (Reactions of Esters)

Methyl formate (Organometallic Reagents) (Reactions of Esters)

Hydrides-LiAlH4 (Reactions of Esters)

Hydrides-RAlH (Reactions of Esters)

Enolates (Reactions of Esters)

Water-acid catalyzed (Reactions of Amides)

Water-base catalyzed (Reactions of Amides)

Hydrides-LiAlH4 (Reactions of Amides)

Hydrides-RAlH (Reactions of Amides)

Enolates (Reactions of Amides)

Amidates (Reactions of Amides)

Hofmann Rearrangement (Reactions of Amides)

Water (Reactions of Nitriles)

Organometallic Reagents (Reactions of Nitriles)

Hydrides-LiAlH4 (Reactions of Nitriles)

Hydrides-RAlH (Reactions of Nitriles)

Catalytic Hydrogenation (Reactions of Nitriles)

electrophilic reactivity of the carbonyl carbon in carboxylic acid derivatives is ____ by ____

1. weakened

2. good e- donating substituents

carboxylic acids derivatives

acyl halides

carboxylic acid derivatives

carboxylic anhydrides

ester derivative

alkyl alkanoates

amide of an alkyl carboxylic acid

alkanamides

alkyl halide with cyanide

alkanenitriles

carboxylic acid derivatives react with ___

water to hydrolyze the carboxylic acid

Carboxylic acid derivatives combine with ____ to give esters and with ____ to give amides

1. alcohols

2. amines

carboxylic acids form ketones with _____

grignard and other organometallic reagents

redcution of a carboxylic acid by hydride gives…

aldehydes, alcohols, or amines

transesterification

can be used to convert one ester into another

.

Acidity of Amines and Amide Formation

Basicity of Amines