α-Methylbenzylamine Functionalized Crown-Ether-Appended Calix[4]arene Phase Transfer Catalyst for Enantioselective Henry Reaction.

Abstract

In this letter, we designed a highly selective α-methylbenzylamine functionalized crown-ether-appended calix[4]arene derived phase transfer catalyst for asymmetric nitroaldol reaction to provide the desired nitroaldol adducts in high yields (up to 99 % yield) with good to excellent enantioselectivities (up to 99.8 % ee).