Catalytic Use of Elemental Gallium for Carbon–Carbon Bond Formation
作者:Bo Qin、Uwe Schneider
DOI:10.1021/jacs.6b06767
日期:2016.10.12
The first catalytic use of Ga(0) in organic synthesis has been developed by using a Ag(I) cocatalyst, crownether ligation, and ultrasonic activation. Ga(I)-catalyzed C-C bondformations between allyl or allenyl boronic esters and acetals, ketals, or aminals have proceeded in high yields with essentially complete regio- and chemoselectivity. NMR spectroscopic analyses have revealed novel transient Ga(I)
1-Arylbut-3-en-1-ols react with trimethyl orthoformate in the presence of Lewis acids like InCl 3 , BiCl 3 , TiCl 4 , or BF 3 ·OEt 2 providing homoallyl ethers or homoallyl chlorides in high yields.