Organic Flashcards
(41 cards)
Ketone -> alcohol
Sodium borohydride, nucleophilic addition
Making grignard reagent
CX + Mg +Ether
Making organolithium
CX + 2xLi + ether
Adding alkyl group to ketone
nucleophilic addition
1) CMgBr
2) H2O
Ketone + water
Hydrate (2 OHs)
Ketone + alcohol
Hemiacetal (1 OH and 1 OR)
Nucleophilic substitution
Hemiacetal-> acetal (2×OR)
React with alcohol (acidic conditions)
Acid catalysis
Carbonyl more electrophilic
Base catalysis
Nucleophile more nucleophilic
Acid chloride -> ester
RO- =nucleophile
Stabilisation of anions
1) electronegative elements
2) delocalisation of -ve charge
3) strength of A-H bond(weaker= more stable)
Reactivity of carbonyl group
1) Inductive effect- neighbouring electronegative groups, increased reactivity
2) Conjugative effect- conjugation=less reactive
Ester -> alcohol (reduction)
LiAlH4- strong, not aqueous
Acid chloride -> alcohol (reduction)
NaBH4- quite weak
Carboxylic acid -> alcohol (reduction)
Borane (BH3)- strongest
Reduction of amide
LiAlH4
RX -> carboxylic acid
Make grignard, then react with CO2
Carbonyl derivative -> carboxylic acid
Add water (hydrolysis) acid or base mediated
Carboxylic acid derivative -> ester
Alcohol (acid mediated only)
Steric hindrance and Sn1
More substituents = more likely, fabrication more stable
Steric hindrance and Sn2
More substituents= less likely- approach of nucleophile more difficult
Hyperconjugation
Sn1 only, no. of groups attached increases reactivity
Pi bond and lone pair donation
Sn1 only
Pi=conjugation, more stable
Lone pair donation strongest
Adjacent double bonds
Sn2 only
Stabilises transition state