Rhodium-Catalyzed Asymmetric 1,4-Addition of Aryltitanium Reagents Generating Chiral Titanium Enolates: Isolation as Silyl Enol Ethers
作者:Tamio Hayashi、Norihito Tokunaga、Kazuhiro Yoshida、Jin Wook Han
DOI:10.1021/ja027663w
日期:2002.10.1
triisopropoxide (ArTi(OPr-i )3) to alpha,beta-unsaturated ketones proceeded with high enantioselectivity (94-99.8% ee) in the presence of 3 mol % of [Rh(OH)((S )-binap)]2 in THF at 20 degrees C to give high yields of the titanium enolates as 1,4-addition products. The titanium enolates were converted into silyl enol ethers by treatment with chlorotrimethylsilane and lithium isopropoxide.