1,8-Diazabicyclo(5.4.0)undec-7-ene → HCID 86604643, compound

Participants

Reaction Steps

A stirred solution of N-(benzyloxycarbonyl)-α-phosphonoglycine trimethyl ester (5.01 g, 15.1 mmol) and 4-methylthiophene-2-carbaldehyde (95a) (2.50 g, 19.8 mmol) in dry dichloromethane (100 mL) was cooled to 0° C. and treated dropwise with DBU (2.76 g, 18.1 mmol). The mixture was warmed to ambient temperature and stirred overnight. The solution was concentrated, taken up in ethyl acetate (150 mL) and washed with 5% hydrochloric acid (2×100 mL). The organic extract was washed with saturated aqueous sodium bicarbonate (2×150 mL), water (200 mL), dried (magnesium sulfate), filtered and evaporated. The residue was purified by crystallization from 4:1 (v/v) ethyl acetate/hexanes to afford the title compound (3.38 g, 67%) as the sole product. 1H NMR (300 MHz, d6-DMSO) δ2.20 (s, 3H), 3.70, (s, 3H), 5.12 (s, 2H), 7.20-7.52 (m, 7H), 7.69 (s, 1H), 8.82 (s, 1H). MS APCI, m/z=354 (M+Na). LC/MS: 2.43 min.

Provenance & Evidence