N,N'-Dimethylethylenediamine → {(3S)-1-[4-(methoxymethyl)-3-oxo-3,4-dihydro-2H-1,4-benzoxazin-6-yl]-5-oxopyrrolidin-3-yl}carbamic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of [(3R)-5-oxopyrrolidin-3-yl]carbamic acid tert-butyl ester (synthesized with reference to WO2004/22536; 1.5 g, 7.49 mmol), 6-bromo-4-(methoxymethyl)-2H-1,4-benzoxazin-3(4H)-one (Reference Examples 36; 2.04 g 7.49 mmol), potassium carbonate (3.11 g, 22.5 mmol), copper (I) iodide (1.43 g, 7.49 mmol), N,N′-dimethylethylenediamine (0.80 ml, 7.49 mmol) and toluene (95 ml) was stirred overnight at 100° C. under a stream of nitrogen gas. After cooling, dichloromethane was added to the reaction solution to remove insoluble material by filtration and the solvent was removed under reduced pressure. The obtained residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to yield 1.79 g (61%) of the title compound in the form of a colorless foamy solid.

Provenance & Evidence