Cerium(III) triflate deprotects p-methoxybenzyl ethers of simple alcohols better than the cerium(III) chloride/sodium iodide system. It can be used in 1% M instead of equimolecular amounts, giving better yields. Aromatic alcohols rearrange, but the addition of a scavenger overcomes thisdrawback. Unfortunately, unsaturated alcohols are deprotected with decomposition, probably due to side electrophilic additions to double bonds. A comparison between the mechanisms of cerium triflate and cerium chloride is reported.
Cerium (III) Triflate versus Cerium (III) Chloride: Anion Dependence of Lewis Acid Behavior in the Deprotection of PMB Ethers / G. Bartoli; R. Dalpozzo; A.o De Nino; L. Maiuolo; M. Nardi; A. Procopio; A. Tagarelli. - In: EUROPEAN JOURNAL OF ORGANIC CHEMISTRY. - ISSN 1434-193X. - STAMPA. - 0:(2004), pp. 2176-2180. [10.1002/ejoc.200400039]
Cerium (III) Triflate versus Cerium (III) Chloride: Anion Dependence of Lewis Acid Behavior in the Deprotection of PMB Ethers
BARTOLI, GIUSEPPE;
2004
Abstract
Cerium(III) triflate deprotects p-methoxybenzyl ethers of simple alcohols better than the cerium(III) chloride/sodium iodide system. It can be used in 1% M instead of equimolecular amounts, giving better yields. Aromatic alcohols rearrange, but the addition of a scavenger overcomes thisdrawback. Unfortunately, unsaturated alcohols are deprotected with decomposition, probably due to side electrophilic additions to double bonds. A comparison between the mechanisms of cerium triflate and cerium chloride is reported.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
