Abstract

A convenient gram-scale method for the preparation of 2-halo-2H-azirine-2-carboxylic acid esters, thioesters and amides via metal-catalyzed isomerization of 5-heteroatom-substituted 4-haloisoxazoles is developed. The formation of the esters and amides is efficiently catalyzed by Rh₂(Piv)₄, while FeCl₂·4H₂O is the catalyst of choice for the synthesis of the thioesters. In addition, rhodium catalysis is successfully applied in the synthesis of azirine-2-carboxylates from non-halogenated 5-alkoxyisoxazoles.

A convenient gram-scale method for the preparation of 2-halo-2H-azirine-2-carboxylic acid esters, thioesters and amides via metal-catalyzed isomerization of 5-heteroatom-substituted 4-haloisoxazoles is developed. The formation of the esters and amides is efficiently catalyzed by Rh₂(Piv)₄, while FeCl₂·4H₂O is the catalyst of choice for the synthesis of the thioesters. In addition, rhodium catalysis is successfully applied in the synthesis of azirine-2-carboxylates from non-halogenated 5-alkoxyisoxazoles.

中文翻译：

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金属催化的5-杂原子取代的异恶唑的异构化为2-卤代-2H-叠氮基的新途径

摘要

开发了一种方便的克级方法，该方法通过5-杂原子取代的4-卤代恶唑的金属催化异构化反应制备2-卤代-2 H-叠氮基-2-羧酸酯，硫代酸酯和酰胺。Rh ₂（Piv）₄可有效催化酯和酰胺的形成，而FeCl ₂ ·4H ₂ O是硫代酯合成的选择催化剂。此外，铑催化已成功地用于由非卤代的5-烷氧基异恶唑合成叠氮基-2-羧酸盐。

开发了一种方便的克级方法，该方法通过5-杂原子取代的4-卤代恶唑的金属催化异构化反应制备2-卤代-2 H-叠氮基-2-羧酸酯，硫代酸酯和酰胺。Rh ₂（Piv）₄可有效催化酯和酰胺的形成，而FeCl ₂ ·4H ₂ O是硫代酯合成的选择催化剂。此外，铑催化已成功地用于由非卤代的5-烷氧基异恶唑合成叠氮基-2-羧酸盐。