The first catalytic approach to the nucleophilic addition of silyl ketene acetals 2 to epoxides 1 is reported. The defined protocol is metal-free using tetrabutylammonioum fluoride as the catalyst. It works in a very efficient manner under solvent-free conditions (SolFC) allowing ?-lactones 3 to be directly obtained with high regioselectivities and yields.
Preparation of Functionalized Alkylmagnesium Derivatives Using an I/Mg-Exchange
作者:Christian B. Rauhut、Viet Anh Vu、Fraser F. Fleming、Paul Knochel
DOI:10.1021/ol8000987
日期:2008.3.1
Functionalized alkylmagnesium reagents bearing an acetal, a ketal, an ester, or a pyridine ring were prepared by an I/Mg-exchange using iPr2Mg.LiCl or ClMg(CH2)5MgCl.2LiCl starting from functionalized primary alkyl iodides.