反应详情

Carbonic acid (1S,4R)-4-(2,6-dichloro-purin-9-yl)-cyclopent-2-enyl ester ethyl ester (1.00 g, 2.92 mmol), propionyl-carbamic acid tert-butyl ester (Intermediate W) (0.55 g, 3.21 mmol) and triphenylphosphine (0.115 g, 0.44 mmol) are placed under an inert atmosphere of Argon. THF (10 ml) is added followed by tris(dibenzylideneacetone)dipalladium(0) (0.13 g, 0.15 mmol). The reaction mixture is stirred at 50° for 1 hour. The solvent is removed in vacuo and purification by chromatography on silica eluting with EtOAc/hexane (1:4) affords the title product. 1H nmr (CDCl3, 400 MHz); 8.70 (s, 1H), 6.15 (m, 1H), 5.85 (m, 1H), 5.80 (m, 1H), 5.60 (m, 1H), 3.15 (m, 1H), 2.75 (q, 2H), 2.10 (m, 1H), 1.55 (s, 9H), 1.15 (t, 3H), MS (ES+) m/e 426 (MH+).

1. customThe solvent is removed in vacuo and purification by chromatography on silica eluting with EtOAc/hexane (1:4)