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Seven-membered rings through metal-free rearrangement mediated by hypervalent iodine.

ABSTRACT: A versatile and metal-free approach for the synthesis of carbocycles and of heterocycles bearing seven- and eight-membered rings is described. The strategy is based on ring expansion of 1-vinylcycloalkanols (or the corresponding silyl or methyl ether) mediated by the hypervalent iodine reagent HTIB (PhI(OH)OTs). Reaction conditions can be easily adjusted to give ring expansion products bearing different functional groups. A route to medium-ring lactones was also developed.

SUBMITTER: Silva SB

PROVIDER: S-EPMC6272645 | biostudies-literature | 2015 Jan

REPOSITORIES: biostudies-literature

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Seven-membered rings through metal-free rearrangement mediated by hypervalent iodine.

Silva Siguara Bastos Lemos SB Torre Adriana Della AD de Carvalho João Ernesto JE Ruiz Ana Lúcia Tasca Gois AL Silva Luiz F LF

Molecules (Basel, Switzerland) 20150115 1

A versatile and metal-free approach for the synthesis of carbocycles and of heterocycles bearing seven- and eight-membered rings is described. The strategy is based on ring expansion of 1-vinylcycloalkanols (or the corresponding silyl or methyl ether) mediated by the hypervalent iodine reagent HTIB (PhI(OH)OTs). Reaction conditions can be easily adjusted to give ring expansion products bearing different functional groups. A route to medium-ring lactones was also developed. ...[more]

PMID: 25599151

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