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Stereoselective synthesis of fused tetrahydroquinazolines through one-pot double [3 + 2] dipolar cycloadditions followed by [5 + 1] annulation.

ABSTRACT: The one-pot [3 + 2] cycloaddition of an azomethine ylide with a maleimide followed by another [3 + 2] cycloaddition of an azide with the second maleimide gives a 1,5-diamino intermediate which is used for a sequential aminomethylation reaction with formaldehyde through [5 + 1] annulation to afford a novel polycyclic scaffold bearing tetrahydroquinazoline, pyrrolidine, pyrrolidinedione, and N-substituted maleimide in stereoselective fashion.

SUBMITTER: Zhang X

PROVIDER: S-EPMC5082442 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Stereoselective synthesis of fused tetrahydroquinazolines through one-pot double [3 + 2] dipolar cycloadditions followed by [5 + 1] annulation.

Zhang Xiaofeng X Pham Kenny K Liu Shuai S Legris Marc M Muthengi Alex A Jasinski Jerry P JP Zhang Wei W

Beilstein journal of organic chemistry 20161018

The one-pot [3 + 2] cycloaddition of an azomethine ylide with a maleimide followed by another [3 + 2] cycloaddition of an azide with the second maleimide gives a 1,5-diamino intermediate which is used for a sequential aminomethylation reaction with formaldehyde through [5 + 1] annulation to afford a novel polycyclic scaffold bearing tetrahydroquinazoline, pyrrolidine, pyrrolidinedione, and <i>N</i>-substituted maleimide in stereoselective fashion. ...[more]

PMID: 27829928

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