González-Delgado JA, Escobar G, Arteaga JF, Barrero AF. Easy access to a cyclic key intermediate for the synthesis of trisporic acids and related compounds.
Molecules 2014;
19:1748-62. [PMID:
24496268 PMCID:
PMC6271007 DOI:
10.3390/molecules19021748]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 01/22/2014] [Accepted: 01/23/2014] [Indexed: 11/16/2022] Open
Abstract
The synthesis of a cyclohexane skeleton possessing different oxygenated functional groups at C–3, C–8 and C–9, and a Δ1,6-double bond has been accomplished in 10 steps with an overall 17% yield. This compound is a key intermediate for access to a wide range of compounds of the bioactive trisporoid family. The synthetic sequence consists of the preparation of a properly functionalized epoxygeraniol derivative, and its subsequent stereoselective cyclization mediated by Ti(III). This last step implies a domino process that starts with a homolytic epoxide opening followed by a radical cyclization and regioselective elimination. This concerted process gives access to the cyclohexane moiety with stereochemical control of five of its six carbon atoms.
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