Potassium Carbonate → 7-[2-(Benzyl-methanesulfonyl-amino)-ethyl]-9-oxa-3,7-diazabicyclo[3.3.1]nonane-3-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A suspension of methanesulfonic acid 2-(benzyl-methanesulfonyl-amino)-ethyl ester (4 g, 0.0130 mol; from step (ii) above), 9-oxa-3,7-diaza-bicyclo[3.3.1]nonane-3-carboxylic acid tert-butyl ester (3 g, 0.013 mol; see WO 01/28992)), dry K2CO3 (3.6 g, 0.026 mol) and lithium bromide (2.2 g, 0.026 mol) in dry acetonitrile (50 ml) was stirred at 60° C. overnight under N2. The reaction mixture was filtered and filtrate was concentrated under reduced pressure. The residue was purified by column chromatography over silica gel using 4% methanol in dichloromethane as eluent to yield (5 g) of the sub-title compound as a solid.

Provenance & Evidence