双官能N,N- '二氧化物催化剂已经被开发用于α的高度对映选择性的硅氰化反应,α二烷氧基酮。此过程中,通过催化的原位制备的脯氨酸衍生Ñ,Ñ '二氧化物2b中,所产生的相应的氰醇三甲基甲硅烷基醚以优良产率(高达99%)的高对映选择性(高达93%ee)的。根据线性效应,1 H NMR谱图,分离的氰醇以及催化剂的NH和N-氧化物部分的作用,提出了合理的机理。
The enantioselectiveStreckerreaction of N-diphenylphosphinoyl ketoimines has been achieved by use of in situ prepared chiral N,N‘-dioxide catalyst from l-piperidinamide 3f and m-chloroperoxybenzoic acid (m-CPBA). Excellent yields (up to 99%) and high enantioselectivities (up to 92% ee) were obtained. In particular, in situ prepared catalyst with readily available chiral material made the procedure
A novel proline-based N,N′-dioxide, which is easily prepared from inexpensive chemicals, serves as an effective catalyst for enantioselective cyanosilylation of aldehydes in up to 73% ee.