Synthesis of Linker Isomers of Quinolin-6-yloxyacetamide Fungicides through Newman–Kwart Rearrangement

Abstract

Novel quinolin-6-ylthioacetamides and quinolin-6-ylpropanamides have been prepared. They are linker isomers of quinolin-6-yloxyacetamide fungicides in which the oxygen atom of the O,S-acetal in the original lead structures has been replaced by either a sulfur atom or a methylene bridge. The Newman–Kwart rearrangement proved to be highly useful for the concise synthesis of the quinolin-6-ylthioacetamides from available quinolinol building blocks.

Key words

quinoline - heterocycles - fungicide - crop protection - Newman–Kwart rearrangement - aldol condensation

• References and Notes

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For some recent applications of the Newman–Kwart reaction, see:
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