Cesium carbonate → HCID 69597607, compound

Participants

Reaction Steps

A solution of [2-(4-benzyloxy-benzenesulfonylamino)-1-methyl-2-(4-methyl-2,6,7-trioxa-bicyclo[2.2.2]oct-1-yl)-ethyl]-carbamic acid benzyl ester (compound of formula LII, 1.2 g, 2.0 mmol) in 2 ml of dimethylformamide was treated with cesium carbonate (1.12 g, 3.4 mmol) and methyl bromoacetate (0.2 ml, 0.32 g, 2.1 mmol). After stirring for about 2 hours, the mixture was diluted with ethyl acetate, washed 5 times with water, and the organic phase was dried over sodium sulfate, filtered and concentrated, affording 1.3 g of {(4-benzyloxy-benzenesulfonyl)-[2-benzyloxycarbonylamino-1-(4-methyl-2,6,7-trioxa-bicyclo[2.2.2]oct-1-yl)-propyl]-amino}-acetic acid methyl ester (compound of formula LIII) as a colorless syrup.

Provenance & Evidence