A highly selective and efficient deprotection of the N‐t‐butoxy carbonyl (N‐Boc) group on indoles, pyrroles, indazoles, and carbolines has been achieved in high yields using a catalytic amount of NaOMe as a base in dry MeOH, at ambient temperature.
EXPERIMENTAL PROCEDURE
To a solution of Boc derivative (0.5 mmol) in dry methanol, a catalytic amount of NaOMe (20 mmol%) was added and stirred at ambient temperature for an appropriate time (Table l). After complete conversion as indicated by thin-layer chromatography (TLC), the reaction mixture was diluted with water(10 ml) and extracted into ethyl acetate (2 20 ml). The combined organic layers were washed with brine, dried over anhydrous Na2SO4, and concentrated under reduced pressure to yield the crude product, which was purified by column chromatography on silica gel to afford the pure Boc deprotected product with 85–98% yield.
Ref:
Synthetic Communications 2007, 37, 281–287
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