TY - JOUR
T1 - Lewis super-acid catalyzed cyclizations: A new route to fragrance compounds
AU - Coulombel, L.
AU - Grau, F.
AU - Weiwer, M.
AU - Favier, I.
AU - Chaminade, X.
AU - Heumann, A.
AU - Bayón, J.C.
AU - Aguirre, P.
AU - Duñach, E.
PY - 2008/12/1
Y1 - 2008/12/1
N2 - This review deals with the application of Lewis super acids such as AlIII, InIII, and SnIV triflates and triflimidates as catalysts in the synthesis of fragrance materials. Novel catalytic reactions involving C-C and C-heteroatom bond-forming reactions, as well as cycloisomerization processes are presented. In particular, SnIV and AlIII triflates were employed as catalysts in the selective cyclization of unsaturated alcohols to cyclic ethers, as well as in the cyclization of unsaturated carboxylic acids to lactones. The addition of thiols and thioacids to non-activated olefins, both in intra- and intermolecular versions, was efficiently catalyzed by InIII derivatives. SnIV Triflimidates catalyzed the cycloisomerization of highly substituted 1,6-dienes to gem-dimethyl-substituted cyclohexanes bearing an isopropylidene substituent. The hydroformylation of these unsaturated substrates, catalyzed by a RhI complex with a bulky phosphite ligand, selectively afforded the corresponding linear aldehydes. The olfactory evaluation of selected heterocycles, carbocycles, and aldehydes synthesized is also discussed. © 2008 Verlag Helvetica Chimica Acta AG, Zürich.
AB - This review deals with the application of Lewis super acids such as AlIII, InIII, and SnIV triflates and triflimidates as catalysts in the synthesis of fragrance materials. Novel catalytic reactions involving C-C and C-heteroatom bond-forming reactions, as well as cycloisomerization processes are presented. In particular, SnIV and AlIII triflates were employed as catalysts in the selective cyclization of unsaturated alcohols to cyclic ethers, as well as in the cyclization of unsaturated carboxylic acids to lactones. The addition of thiols and thioacids to non-activated olefins, both in intra- and intermolecular versions, was efficiently catalyzed by InIII derivatives. SnIV Triflimidates catalyzed the cycloisomerization of highly substituted 1,6-dienes to gem-dimethyl-substituted cyclohexanes bearing an isopropylidene substituent. The hydroformylation of these unsaturated substrates, catalyzed by a RhI complex with a bulky phosphite ligand, selectively afforded the corresponding linear aldehydes. The olfactory evaluation of selected heterocycles, carbocycles, and aldehydes synthesized is also discussed. © 2008 Verlag Helvetica Chimica Acta AG, Zürich.
U2 - 10.1002/cbdv.200890086
DO - 10.1002/cbdv.200890086
M3 - Review article
SN - 1612-1872
VL - 5
SP - 1070
EP - 1082
JO - Chemistry and Biodiversity
JF - Chemistry and Biodiversity
IS - 6
ER -