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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Efficient synthesis of highly functionalized cyclic aminimides
Bongjin Moon1, Sangbae Han, Dohyung Kim
1Department of Chemistry, Sogang University, Seoul, Korea. hjmoon@sogang.ac.kr
Abstract:
[reaction: see text]. Simple condensation reactions of various alpha,beta-epoxy or alpha,beta-aziridinyl methyl esters with 1,1-dialkyl hydrazines provided cyclic aminimides (1,1-dialkyl-3-oxopyrazolidines) with a heteroatom substituent at the 4-position in good yields. The reaction proceeds smoothly, without any coreagent, providing the product as an easily isolable precipitate. The reaction is expected to be a good candidate for combinatorial synthesis of a highly functionalized five-membered ring scaffold. The scope and limitations of this reaction were investigated by varying the substituents R(1)-R(5).
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