Practical synthesis of optically active amino alcohols via asymmetric transfer hydrogenation of functionalized aromatic ketones.
2-Substituted acetophenones such as 2-cyano-, 2-azido-, or 2-nitroacetophenones were effectively reduced with a mixture of HCOOH/N(C(2)H(5))(3) containing a chiral Ru(II) catalyst, RuCl[(S,S)-N-(p-toluenesulfonyl)-1,2-diphenylethylenediamine](p-cymene), giving the corresponding optically active alcohols, which can be converted to optically active amino alcohols with excellent ee's. Similarly, the reaction of 2-benzoylacetophenone with the same Ru catalyst gave a quantitative yield of the corresponding optically active 1,3-diol with 99% ee.
Watanabe
Masahito
M
Central Research Laboratory of Kanto Chemical Corp., Inc., 1-7-1 Inari, Soka, Saitama, Japan.
Murata
Kunihiko
K
Ikariya
Takao
T