Camphor Mannich reaction

Among terpenoid substrates bearing the alkyl ketone moiety, 4-caranone" and 2-pincne-4-one," in addition to camphor, are worth mentioning. The stereoselectivity of aminomethylation" is remarkably affected by the reaction conditions moreover, the tendency of 2-pinene-4-one, like steroid substrates, to give the vinylogous Mannich base (Table 8, Chap. I, C. 1) is important. 

K. Kundu, S. K. Nayak, RSC Adv. 2012, 2, 480-486. ( )-Camphor-lO-sulfonic acid catalyzed direct one-pot three-component Mannich type reaction of alkyl (hetero)aryl ketones under solvent-free conditions application to the synthesis of aminochromans. 

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