Syntheses of a potential fluorescence probe,(-)-(R)-7-azatryptophan, via alkylation of the (1 R, 4 R)-camphor imine of tert-butylgycinate

R Sánchez-Obregón, AG Fallis…

Index: Sanchez-Obregon, Ruben; Fallis, Alex G.; Szabo, Arthur G. Canadian Journal of Chemistry, 1992 , vol. 70, # 5 p. 1531 - 1536

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Citation Number: 11

Abstract

The synthesis of (-)-(R)-7-azatryptophan (2) from commercially available 7-azaindole (4) is described. The key step involved the diastereoselective alkylation of tert-butyl [(1 R, 4 R)- bornylideneamino] acetate (3) with 1-(tert-butyloxycarbonyl-3-(iodomethyl)-7-azaindole (19) derived from 3-formyl-7-azaindole (14). The alkylation, conducted at-100° C in a THF/HMPA solvent using potassium hexamethyldisilazide as the base, afforded 7 in greater than 98% ...