| Abstract
| - Aryl methyl ethers, methyl esters, aryl esters, and aryl sulfonates are chemoselectively deprotectedunder nonhydrolytic conditions by treatment with Ph2S2 (0.6 equiv) and Na (1.6 equiv) in NMPunder reflux or at 90 °C. Quantitative utilization of the ‘PhS' moiety as the effective nucleophilicspecies represents conservation of atom economy. Other solvents such as HMPA, DMPU, DMEU,and DMF afforded comparable results. Chloro, nitro, aldehyde, α,α-diketone, and α,β-unsaturatedketone functionalities remain unaffected. The deprotection was found to take place in the orderaryl ester > alkyl ester > aryl alkyl ether. Substrates bearing strong electron-withdrawing groupsreact at a faster rate than those not having such substitution. The differences in rate of reactionhas been exploited for selective deprotection for intramolecular competition. An aryl acetate/benzoateis deprotected selectively in preference to a methyl ester or aryl methyl ether. Selective deprotectionof a methyl ester is observed in the presence of an aryl alkyl ether.
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