Chiral spiroaminoborate ester as a highly enantioselective and efficient catalyst for the borane reduction of furyl, thiophene, chroman and thiochroman containing ketones.
Prochiral heteroaryl ketones containing furan, thiophene, chroman and thiochroman moieties were successfully reduced in the presence of 1 - 10 mol % of spiroaminoborate ester 1 with different borane sources to afford non-racemic alcohols in up to 99% ee. In addition, modest enantioselectivity, around 80% ee, was achieved in the reduction of linear α,β-unsaturated heteroaryl ketones.
Stepanenko
Viatcheslav
V
Department of Chemistry, University of Puerto Rico-Humacao, CUH Station Humacao, Puerto Rico 00791, USA.
De Jesús
Melvin
M
Correa
Wildeliz
W
Bermúdez
Lorianne
L
Vázquez
Cindybeth
C
Guzmán
Irisbel
I
Ortiz-Marciales
Margarita
M