Soluble LnCl₃·2LiCl for the Improved 1,2-Addition of Grignard Reagents

Significance

The reaction of Grignard reagents with carbonyl compounds to form alcohols is of enormous value for organic synthesis. However, this process very often suffers from side reactions like enolization or reduction. Use of CeCl₃ allowed solving these problems to some extent, but in many cases, especially for functionalized Grignard reagents, 1,2-addition to carbonyl compounds was very difficult to perform. The introduction of soluble LnCl₃·2LiCl offers an attractive solution to this problem. Practically in all cases the yields of products exceed 60%, and mostly are above 90%. The reaction mixture is homogeneous and the process successfully proceeds at temperatures above -30 °C.