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Cl3CCONH2/PPh3 was a versatile reagent to convert carboxylic acids into their corresponding acid chlorides. This intermediate was clearly confirmed by spectroscopic methods (IR, 1H, 13C NMR). This one-pot reaction of in situ acid chloride generated with various alcohols successfully furnished the corresponding esters in moderate to excellent yields.

A convenient one-pot process for preparing various esters from carboxylic acids using the Ph3P-CCl3CN has been developed. Racemic α-tocopherol, clofibrate and flavoxate were prepared in high yields using this method.

Enantiomerically pure unnatural (R)-malic acid derivatives were prepared from (R,R)-tartrates via their cyclic thionocarbonate derivatives using phenylsilanes in high isolated yields.

Various carboxylic acids are converted into the corresponding carboxylic acid anhydrides treated with trichloroacetonitrile and triphenylphosphine in the presence of triethylamine at room temperature.

Reaction of cyclic sulfates of vic-diols with sodium hydroxide in THF-MeOH produced the corresponding epoxides in excellent isolated yields at room temperature. Cyclic sulfates of trans-diols gave cis-epoxides, and cyclic sulfates of cis-diols afforded trans-epoxides exclusively. Various cyclic sulfates of vic-diols can be converted into the epoxides under the conditions.

Various S-methyl dithiocarbonates of tertiary and secondary alcohols are effectively deoxygenated in high isolated yields by treatment with diphenylphosphine oxide and various radical initiators in boiling dioxane. Deoxygenation of S-methyl dithiocarbonate of primary alcohols can be accomplished similarly in boiling xylenes.

Reaction of cyclic sulfates of vic-diols with magnesium iodide in acetonitrile produced the corresponding olefins in excellent isolated yields at room temperature. Cyclic sulfates of trans-diols gave trans-alkenes exclusively. Cyclic sulfates of cis-diols gave a mixture of cis- and trans- alkenes. However, the cyclic sulfate of cyclic cis-diol afforded the corresponding cis-alkene only.

Phenylsilane has been used for the reduction of alkyl and aryl halides. The method offers mild, neutral reaction conditions, easy work-up process, and high yields of the dehalogenated products.