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Phosphine-Catalyzed [3+2] and [4+3]Annulation Reactions of C,N-Cyclic Azomethine Imines with Allenoates.

ABSTRACT: Phosphine-catalyzed [3+2] and [4+3]annulation reactions of C,N-cyclic azomethine imines with allenoates have been developed to give a variety of pharmaceutically attractive tetrahydroisoquinoline derivatives in moderate to excellent yields. The two distinct reaction pathways, [3+2] and [4+3]cyclization, depend on the nature of the nucleophilic phosphine and the allenoate. Generally, for ?-alkylallenoates, the reactions always proceed with [3 +2]cyclization as the major pathway no matter what phosphine was used; for ?-ArCH2-substituted allenoates, the reaction pathway was controlled by the phosphine catalyst used.

SUBMITTER: Jing C

PROVIDER: S-EPMC4266944 | biostudies-literature | 2012 Apr

REPOSITORIES: biostudies-literature

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Phosphine-Catalyzed [3+2] and [4+3]Annulation Reactions of C,N-Cyclic Azomethine Imines with Allenoates.

Jing Chengfeng C Na Risong R Na Risong R Wang Bo B Liu Honglei H Zhang Lei L Liu Jun J Wang Min M Zhong Jiangchun J Kwon Ohyun O Guo Hongchao H

Advanced synthesis & catalysis 20120401 6

Phosphine-catalyzed [3+2] and [4+3]annulation reactions of C,N-cyclic azomethine imines with allenoates have been developed to give a variety of pharmaceutically attractive tetrahydroisoquinoline derivatives in moderate to excellent yields. The two distinct reaction pathways, [3+2] and [4+3]cyclization, depend on the nature of the nucleophilic phosphine and the allenoate. Generally, for α-alkylallenoates, the reactions always proceed with [3 +2]cyclization as the major pathway no matter what pho ...[more]

PMID: 25525424

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