REDUCTION OF REPRESENTATIVE ORGANIC FUNCTIONAL-GROUPS WITH GALLANE-TRIMETHYLAMINE

The rates and stoichiometry of the reaction of gallane-trimethylamine with selected organic compounds containing representative functional g roups were examined in tetrahydrofuran solution under standardized con ditions (THF, 0 degrees C). And its reducing characteristics were comp ared with those of aluminum hydridetriethylamine(AHTEA). The rate of h ydrogen evolution from active hydrogen compounds varied considerably w ith the nature of the functional group and the structure of the hydroc arbon moiety. Alcohols, phenol, amines, thiols evolved hydrogen rapidl y and quantitatively. Aldehydes and ketones were reduced moderately to the corresponding alcohols. Cinnamaldehyde was reduced to cinnamyl al cohol, which means that the conjugated double bond was not attacked by gallane-trimethylamine. Carboxylic acids, esters, and lactones were s table to the reagent under standard conditions. Acid chlorides also we re rapidly reduced to the corresponding alcohols. Epoxides and halides were inert to the reagent. Caproamide and nitrile were stable to the reagent, whereas benzamide was rapidly reduced to benzylamine. Nitropr opane, nitrobenzene and azoxybenzene were stable to the reagent, where as azobenzene was reduced to 1,2-diphenylhydrazine. Grimes and pyridin e N-oxide were reduced rapidly. Di-n-butyl disulfide and dimethylsulfo xide were reduced only slowly, but diphenyl disulfide was reduced rapi dly. Finally, sulfones and sulfonic acids were inert to the reagent un der the reaction.