Methyl propiolate → CGP-47292 methyl ester

Reaction equation

[F:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]([F:12])[C:3]=1[CH2:4][N:5]=[N+:6]=[N-:7].[C:13]([O:17][CH3:18])(=[O:16])[C:14]#[CH:15].O=C1O[C@H]([C@H](CO)O)C(O)=C1O>C(O)C>[F:1][C:2]1[CH:11]=[CH:10][CH:9]=[C:8]([F:12])[C:3]=1[CH2:4][N:5]1[CH:15]=[C:14]([C:13]([O:17][CH3:18])=[O:16])[N:7]=[N:6]1

Participants

Procedure

2,6-Difluorobenzyl azide (3.0 g, 17.7 mmoles) is suspended in ethanol (30 ml), then methyl propiolate (IV) (1.6 g, 19.6 mmoles), ascorbic acid (317 mg, 1.8 mmoles) and CuSO4 pentahydrate (50 mg, 0.18 mmole) are added. The reaction mixture is kept at 25° C. under stirring overnight. The mixture is concentrated, taken up with ethyl acetate and washed with an ammonia diluted solution. The organic phase is dried, filtered, concentrated under reduced pressure. A crystalline white solid is obtained in 94% yield.