Ionic polymer-supported O-trimethylsilyl-α,α-diphenyl-(S)-prolinols as recoverable organocatalysts for the asymmetric Michael reactions of carbon acids with α,β-enals

A recyclable organocatalyst bearing O-trimethylsilyl-alpha,alpha-diphenyl-(S)-prolinol unit tagged to the imidazolium cation and poly(4-styrene-sulfonate) anion in the reaction of CH-acids with alpha,beta-enals provided the respective Michael adducts in high yields (up to 99%) and with high enantioselectivities (up to 98% ee).