Benzyldimethylanilinium hydroxide

Chloro-2-hydroxybenzophenone added to a soln. of tryptophan in benzyldi-methylanilinium hydroxide, allowed to stand overnight over molecular sieve 3 A, filtered, excess benzyldimethylanilinium hydroxide removed in vacuo, and the residue refluxed 1 hr. in toluene product. Y 74%. - By this method, acid-sensitive amino acids can be converted into their benzyl esters. K. Williams and B. Halpern, Australian J. Chem. 28, 2065 (1975). 

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