Triethylamine → HCID 58428062, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-(2,5-dimethyl-phenyl)-4-hydroxy-8-methoxy-1-methoxymethoxy-1,8-diaza-spiro[4.5]dec-3-en-2-one (9.0 g, 24.83 mmol), triethylamine (6.9 ml, 5.0 g, 49.66 mmol) and 4-dimethylaminopyridine (100 mg, 0.82 mmol) in tetrahydrofuran (250 ml) at 0° C. was added a solution of ethyl chloroformate (3.09 ml, 3.5 g, 32.28 mmol) in tetrahydrofuran (20 ml) dropwise. The suspension was stirred at 0° C. for one hour, and at room temperature for one hour. The reaction mixture was evaporated, diluted with ethyl acetate and filtered to remove salts. The filtrate was washed with a saturated aqueous sodium hydrogen carbonate solution (2×100 ml) and brine, dried over sodium sulfate and concentrated. The oily residue was purified by chromatography on silica gel (ethyl acetate/hexane 1:1). Yield: 9.63 g of carbonic acid 3-(2,5-dimethyl-phenyl)-8-methoxy-1-methoxy-methoxy-2-oxo-1,8-diaza-spiro[4.5]dec-3-en-4-yl ester ethyl ester (title compound P1ii.2) as a white solid, mp 109-111° C.

Provenance & Evidence