Heptanoic acid, 7-oxo-, ethyl ester → rac-5-(7-Ethoxy-7-oxoheptyl)-2,3-diphenyl-5,6,7,8-tetrahydropyrido[2,3-b]pyrazine-7,8-diyl diacetate

Participants

Reaction Steps

To a solution of rac-2,3-diphenyl-5,6,7,8-tetrahydropyrido[2,3-b]pyrazine-7,8-diyl diacetate (Intermediate I) (69 mg, 0.171 mmol) in DCE (3 ml) was added ethyl 7-oxoheptanoate (88 mg, 0.513 mmol) followed by sodium triacetoxyborohydride (109 mg, 0.513 mmol). The reaction was left to stir overnight at room temperature under an atmosphere of nitrogen. To the reaction mixture was added further ethyl 7-oxoheptanoate (88 mg, 0.513 mmol) followed by sodium triacetoxyborohydride (109 mg, 0.513 mmol). The reaction mixture was left to stir at RT under an atmosphere of nitrogen for 4 days. The mixture was diluted with water and extracted with EtOAc (3×20 ml). The combined organic extracts were dried over MgSO4, filtered and concentrated in vacuo. The resulting crude product was purified by chromatography on silica eluting with 0-70% EtOAc/iso-hexane to afford the title compound;

Provenance & Evidence