Isoindolinones as Michael donors under phase transfer catalysis: enantioselective synthesis of phthalimidines containing a tetra-substituted carbon stereocenter

摘要

Readily available chiral ammonium salts derived from cinchona alkaloids have\udproven to be effective phase transfer catalysts in the asymmetric Michael reaction of\ud3-substituted isoindolinones. This protocol provides a convenient method for the\udconstruction of valuable asymmetric 3,3-disubstituted isoindolinones in high yields and\udmoderate to good enantioselectivity. Diastereoselectivity was also investigated in the\udconstruction of contiguous tertiary and quaternary stereocenters. The use of acrolein as\udMichael acceptor led to an interesting tricyclic derivative, a pyrroloisoindolinone analogue,\udvia a tandem conjugated addition/cyclization reaction.