A cheap, less problematic, efficient and selective reagent for the rem
oval of the t-butyl and 1-adamantyl protecting groups from carboxylic
esters was found to be commercial 100% HNO3 in CH2Cl2. Incidentally, 1
,1-dimethylethyl nitrate and tricyclo[3.3.1.1(3,7)]dec-1-yl (1-adamant
yl) nitrate are coproducts in a clean reaction. The procedure is in ma
ny ways superior to the method employing CF3COOH. (C) 1998 Published b
y Elsevier Science Ltd. All rights reserved.