Practical asymmetric Mukaiyama-Michael reaction of benzalacetone derivatives catalyzed by allo-threonine-derived oxazaborolidinone.
In the presence of 2,6-diisopropylphenol and t-BuOMe (1 equiv. each), asymmetric Mukaiyama-Michael reaction of a variety of benzalacetone derivatives 2 with silyl ketene acetal 3 is efficiently catalyzed by O-(2-naphthoyl)-N-tosyl-(L)-allo-threonine-derived B-phenyloxazaborolidinone 1 (10 mol%) to give the corresponding adducts 5 in 60-90% ee.
Wang
Xiaowei
X
Department of Chemistry and Materials Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan.
Harada
Toshiro
T
Iwai
Hiroyoshi
H
Oku
Akira
A
D000096:Acetone / Q000031:analogs & derivatives* / Q000737:chemistry*; D001555:Benzene Derivatives / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure; D010080:Oxazoles / Q000138:chemical synthesis / Q000737:chemistry*; D013237:Stereoisomerism; D013912:Threonine
D001555:Benzene Derivatives; D010080:Oxazoles; D000096:Acetone; D013912:Threonine