Direct catalytic enantio- and diastereoselective aldol reaction using a Zn-Zn-linked-BINOL complex: a practical synthesis of syn-1,2-diols.
[reaction: see text] The direct catalytic enantio- and diastereoselective aldol reaction with 2-hydroxy-2'-methoxyacetophenone proceeded smoothly using as little as 1 mol % of a dinuclear zinc catalyst, Zn-Zn-linked-BINOL complex 2, to afford alpha,beta-dihydroxy ketones in a highly syn-selective manner (up to syn/anti 97/3) and in excellent yields (up to 95%) and ees (up to 99%). Efficient transformations of the alpha,beta-dihydroxy ketone into an alpha,beta-dihydroxy ester and an alpha,beta-dihydroxy amide via regioselective rearrangements are also described.
Kumagai
N
N
Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Matsunaga
S
S
Yoshikawa
N
N
Ohshima
T
T
Shibasaki
M
M