A new lithium alkoxide accelerated diastereoselective cyanation of ketones.
[reaction: see text] A remarkably general lithium heteroatom assisted TMSCN or TBSCN addition to aldehydes and ketones has been discovered. The process provides excellent selectivities and high rates. Conformationally constrained ketones such as camphor, fenchone, and nopinone give excellent diastereoselectivities with TMSCN. Reduction of 2 provided diastereopure amino alcohol 3 in good yield. alpha- and beta-Methyl cyclohexanones with TBSCN-LiOR afford high diastereoselectivities and yields.
Wilkinson
H S
HS
Chemical Research and Development, Sepracor Inc., 111 Locke Drive, Marlborough, Massachusetts 01752, USA.
Grover
P T
PT
Vandenbossche
C P
CP
Bakale
R P
RP
Bhongle
N N
NN
Wald
S A
SA
Senanayake
C H
CH