FORMATION AND CLEAVAGE OF ETHERS

Uses of FeCl3/Ac20 methodology in synthesis include the taxusin synthesis of Holton et al. (Sch. 2) [15], the Forsyth and Clardy synthesis of (+)-didemnenones A and B [16], and the synthesis of a nodulation factor (NodRf-III) by Fraser-Reid and coworkers [17]. 

The direct transformation of silyl ethers into esters can also be performed by reaction with an acid chloride in CH2CI2 (0 °C to room temperature) in the presence of FeCls (1.5 equiv.) [18]. The formation of allyl ethers from allylic alcohols and methanol is catalyzed by RUCI3 [19]. The reaction is likely to occur via a jr-allyl Ru intermediate. Allylic rearrangements and racemization of optically active allylic alcohols take place. 

Ruthenium in Organic Synthesis. Shun-Ichi Murahashi (Ed.) 

Copyright 2004 WILEY-VCH Verlag GmbH Co. KGaA, Weinheim ISBN 3-527-30692-7 

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