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?,?-Unsaturated Gold(I) Carbenes by Tandem Cyclization and 1,5-Alkoxy Migration of 1,6-Enynes: Mechanisms and Applications.

ABSTRACT: 1,6-Enynes bearing OR groups at the propargyl position generate ?,?-unsaturated gold(I)-carbenes/ gold(I) stabilized allyl cations that can be trapped by alkenes to form cyclopropanes or 1,3-diketones to give products of ?-alkylation. The best migrating group is p-nitrophenyl ether, which leads to the corresponding products without racemization. Thus, an improved formal synthesis of (+)-schisanwilsonene A has been accomplished. The different competitive reaction pathways have been delineated computationally.

SUBMITTER: Calleja P

PROVIDER: S-EPMC5132047 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature

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α,β-Unsaturated Gold(I) Carbenes by Tandem Cyclization and 1,5-Alkoxy Migration of 1,6-Enynes: Mechanisms and Applications.

Calleja Pilar P Pablo Óscar Ó Ranieri Beatrice B Gaydou Morgane M Pitaval Anthony A Moreno María M Raducan Mihai M Echavarren Antonio M AM

Chemistry (Weinheim an der Bergstrasse, Germany) 20160816 38

1,6-Enynes bearing OR groups at the propargyl position generate α,β-unsaturated gold(I)-carbenes/ gold(I) stabilized allyl cations that can be trapped by alkenes to form cyclopropanes or 1,3-diketones to give products of α-alkylation. The best migrating group is p-nitrophenyl ether, which leads to the corresponding products without racemization. Thus, an improved formal synthesis of (+)-schisanwilsonene A has been accomplished. The different competitive reaction pathways have been delineated com ...[more]

PMID: 27527611

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