This work represents the first example of a gold-catalyzed formation of 1,3-thiazine/1,3-thiazinane by means of a catalytic approach and further uncommon isolation of the two tautomers. The developed protocol gives rise to a broad scope of 1,3-thiazine derivatives with excellent yields in short reaction times. Interestingly, different isomers could be obtained depending on the state of the compound, and in the crystal state the 1,3-thiazinane isomer is obtained, while in solution the 1,3-thiazine is the unique isomer. This work represents an interesting approach for the synthesis of potential biologically relevant molecules and a crucial precedent in tautomerism isolation and characterization.

中文翻译：

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金催化的 1,3-噻嗪形成和罕见的互变异构体分离

这项工作代表了金催化形成 1,3-噻嗪/1,3-噻嗪烷的第一个例子，该方法通过催化方法和进一步不常见的两种互变异构体分离。开发的协议产生了广泛的 1,3-噻嗪衍生物，在较短的反应时间内具有出色的收率。有趣的是，根据化合物的状态可以得到不同的异构体，在晶体状态下得到1,3-噻嗪异构体，而在溶液中则得到1,3-噻嗪异构体。这项工作代表了一种有趣的方法，用于合成潜在的生物学相关分子，并且是互变异构分离和表征的重要先例。