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2 Chiral Ammonium Betaine-Catalyzed Mannich Reactions [Pg.822]

Quaternary ammonium betaines possessing an anion moiety have emerged as Br0nsted base catalysts. The Cj-symmetric axially chiral ammonium betaine 177 deprotonates the a-substituted a-nitrocarboxylates (176) to form a structured ion pair that reacts with imines (173) to furnish the corresponding antt-Mannich [Pg.822]

Scheme 28.19 Chiral ammonium betaine catalyzed Mannich reactions.

See other pages where Chiral Ammonium Betaine-Catalyzed Mannich Reactions is mentioned: [Pg.823] [Pg.823] [Pg.69]