Straightforward synthesis of a vicinal double bridgehead iodo trimethylsilyl octacycle: unprecedented lack of reactivity of the silyl group in front of fluoride anions.

Abstract: A convenient synthesis of an octacyclic compound containing an iodo and a trimethylsilyl group in vicinal double bridgehead positions, as a possible precursor of a pyramidalized alkene, is described. The key step of the synthesis consists of a double nucleophilic substitution of two neopen...

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Bibliographic Details
Authors: Camps García, Pelayo, Lozano Mena, David, Guitián, E., Peña, D., Pérez, D., Font Bardia, Ma. Mercedes, Llamas-Saíz, A.L.
Format: article
Status:Versión aceptada para publicación
Publication Date:2017
Country:España
Institution:Universidad de Barcelona
Repository:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/163240
Online Access:https://hdl.handle.net/2445/163240
Access Level:Open access
Keyword:Reaccions químiques
Cicles biogeoquímics
Chemical reactions
Biogeochemical cycles
Description
Summary:Abstract: A convenient synthesis of an octacyclic compound containing an iodo and a trimethylsilyl group in vicinal double bridgehead positions, as a possible precursor of a pyramidalized alkene, is described. The key step of the synthesis consists of a double nucleophilic substitution of two neopentyl-type iodides by cyclopentadienide anions followed by two intramolecular Diels-Alder cycloadditions. All attempts to generate the expected pyramidalized alkene from the above precursor on reac-tion with different sources of fluoride failed. This octacyclic compound, which contains two disubstituted C=C bonds, underwent a chemo- and stereoselective Pd0-catalyzed co-cyclotrimerization with dimethyl acetylenedicarb-oxylate to give a nonacyclic cyclohexadiene derivative that can be aromatized upon reaction with CsF or transformed into a related fluoride upon reaction with AgF.