Benzyl Alcohol → Trans 2-benzyloxycarbonylamino-3-carboethoxy-1,2,3,4-tetrahydronaphthalene

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of trans 2-carboethoxy-3-carboxy-1,2,3,4-tetrahydronaphthalene (546 mg, 2.2 mmol) in toluene (15 mL) under nitrogen was added diphenylphosphoryl azide (0.62 mL, 2.86 mmol), triethylamine (0.4 mL, 2.86 mmol) and benzyl alcohol (1.14 mL, 11 mmol). The reaction mixture was heated to 100° C. for 19 h. The toluene was removed under vacuum to yield a residue. The residue was diluted with ethyl acetate and aqueous ammonium chloride solution. The organic layer was washed with 1.0 M aqueous hydrochloric acid solution, saturated aqueous sodium carbonate solution and brine, dried over anhydrous magnesium sulfate, and concentrated under vacuum to yield a residue. The residue was purified by silica gel chromatography (10% ethyl acetate in hexane was used) to obtain the title compound (800 mg, containing some benzyl alcohol). 13C NMR (500 MHz, CDCl3) δ 173.2, 155.5, 136.3, 133.5, 133.2, 129.0, 128.5, 128.1, 127.6, 126.9, 126.4, 126.3, 66.7, 65.3, 48.7, 45.3, 35.0, 30.4, 14.1. 1H NMR (400 MHz, CDCl3) δ 7.02-7.38 (m, 9H), 5.10 (s, 2H), 4.29 (m, 1H), 4.14 (m, 2H), 3.22 (m, 2H), 3.02 (dd, J=5.7, 17.2 Hz, 1H), 2.88 (m, 1H), 2.76 (dd, J=7.2, 16.8 Hz, 1H), 1.23 (t, J=7.0 Hz, 3H).

Provenance & Evidence