Organic Chemistry Aldehydes And Ketones - Nucleophillic Addition Of Hcn: Cyanohydrin Formation

Front 1

Aldehydes and unhindered ketones react with HCN to yield ?

Back 1

cyanohydrins, RCH(OH)C=-N

Front 2

cyanohydrin formation is ?

Back 2

reversible and base-catalyzed.

Front 3

Addition of HCN rxns occur _______ when pure HCN is used but ______ when a small amount of a base is added to generate the nucleophilic cyanide ion, CN-.

Back 3

- slowly

- rapidly

Front 4

a small amount of ____ can be added to HCN to catalyze the rxn

Back 4

KCN

Front 5

Addition of CN- to an aldehyde or ketone occurs by _____________________________ , yielding a _______ _______ that is protonated by HCN to give

Back 5

- a typical nucleophilic addition pathway

- tetrahedral intermediate

- cyanohydrin product plus regenerated CN-

Front 6

Cyanohydrin formation is unusual because ?

Back 6

it is one of the few examples of the addition of a proticacid (H-Y) to a carbonyl group

Front 7

Reagents such as H2O, HBr, HCL. and H2SO4 don't normally yield carbonyladditionproducts because their equilibrium constants for rxn are unfavorable. With HCN, the equilibrium favors

Back 7

the cyanohydrin adduct