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Letters in Organic Chemistry

Author(s): Dau Xuan Duc*

DOI: 10.2174/1570178618666210120110111

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Studies Towards the Synthesis of the Pyrido[1,2-a]azepine Alkaloids

Page: [532 - 541] Pages: 10

  • * (Excluding Mailing and Handling)

Abstract

This study describes the synthesis of the pyrido[1,2-a]azepine alkaloids. The bicyclic compound 1 containing the A-B core ring structure was synthesized in 17 steps in 1.7% overall yield starting from 4-pentyn-1-ol. The key steps involve an oxidation of 1,4 diol to lactone and an ene-yne ring closing metathesis reaction.

Keywords: Pyrido[1, 2-a]azepine, Stemona alkaloids, bromolactonization, aminolysis reaction, ene-yne lactam, vinyl iodide.

Graphical Abstract

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