Tributylphosphine → 7-[2-Methoxy-4-(2-methylbenzoyloxy)phenyl]-8-(2-methoxy-5-nitrophenoxymethyl)-3,3-dimethyl-3,4-dihydro-1H-quinoxalin-2-one

Participants

Reaction Steps

A mixture of 8-hydroxymethyl-7-[2-methoxy-4-(2-methylbenzoyloxy)phenyl]-3,3-dimethyl-3,4-dihydro-1H-quinoxalin-2-one (Reference Compound No. 23, 40.1 mg, 0.0898 mmol), 2-methoxy-5-nitrophenol (22.8 mg, 0.135 mmol), and tri n-butylphosphine (33.7 μL, 0.135 mmol) was dissolved in anhydrous tetrahydrofuran (1 mL), 1,1′-(azodicarbonyl)dipiperidine (34.0 mg, 0.135 mmol) was added thereto, and then the mixture was stirred at room temperature. After 20 minutes, 2-methoxy-5-nitrophenol (23.1 mg, 0.137 mmol), tri n-butylphosphine (33.7 μL, 0.135 mmol), and 1,1′-(azodicarbonyl)dipiperidine (33.9 mg, 0.134 mmol) were added thereto, and after 80 minutes, 2-methoxy-5-nitrophenol (22.9 mg, 0.135 mmol), tri-n-butylphosphine (33.7 μL, 0.135 mmol), and 1,1-(azodicarbonyl)dipiperidine (34.0 mg, 0.135 mmol) were added further. The stir was stopped 3 hours later and the reaction mixture was concentrated. The obtained residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give the titled compound (22.1 mg) as a pale yellow amorphous product. (Yield 41%)

Provenance & Evidence