Low ligand loading, highly enantioselective addition of phenylacetylene to aromatic ketones catalyzed by Schiff-base amino alcohols.
[reaction: see text] Schiff-base amino alcohols 7a,b derived from L-phenylglycine through three simple steps are found to be highly effective for the enantioselective addition of phenylacetylene to aromatic ketones. When the loading of 7b was 1 mol %, an ee value of up to 95% was obtained. However, when 7b was lowered to 0.1 mol %, a high ee value of 85% was still achieved. A practical solution to synthesize the optically active tertiary propargylic alcohols was described.
Chen
Chao
C
Department of Biochemistry and Molecular Biology, School of Life Sciences, Lanzhou University, Gansu, China.
Hong
Liang
L
Xu
Zhao-Qing
ZQ
Liu
Lei
L
Wang
Rui
R