Reactions of Aldehydes & Ketones
(Carey, Chap. 17)

Reaction Product Notes
 
Hydrate formation
Equilibrium; K usually < 1
 
Hemiacetal formation
Equilibrium; K usually < 1,
   except for 5-6 memb cyclic
 
Acetal formation
Reverse reaction, acetal
   hydrolysis
C=O "protecting" group
 
 
Thioacetal formation
 
 
Thioacetal hydrogenolysis
Y = H or R", imine
Y = OH, oxime
Y = NH2 or NHR", hydrazone
2,4-DNP diagnostic for alde. or
   ketone - get orange ppt
 
 
Amine synthesis
 
"Wolff-Kishner reduction"
Decomposition of hydrazone

 
Cyanohydrin formation
Equilibrium; K > 1 only
   with alde. or cyclic ketone

 
Cyanohydrin hydrolysis
Carboxylic acid synthesis
 
 
Alcohol synthesis
Prep of 1o or 2o alcohols
NaBH4 selective for alde. or
   ketones
 
"Wittig reaction"
Synthesis of alkenes
R'' and/or R''' can be H
Ag+/HO- ("Tollen's reagent") -
selective for aldehydes;
diagnostic - get silver mirror
"Baeyer-Villiger oxidation"
Cation rearrangement
Migratory aptitudes:
   Ar>3oR>2oR>1oR>CH3

schwartz@chem.fsu.edu