Triethylamine → 3-[2-(Trimethylsilyl)ethoxycarbonylamino]-4-ethyl-9-isopropyl-9H-pyrido[3,4-b]indole

Participants

Reaction Conditions

Reaction Steps

Diphenyl phosphoryl azide (0.15 ml, 0.69 mmol) was added to a stirred solution of 3-carboxy-4-ethyl-9-isopropyl-9H-pyrido[3,4-b]indole (Method 3; 186 mg, 0.66 mmol) and triethylamine (0.1 ml, 0.69 mmol) in toluene (5 ml). The mixture was heated to 80° C. for 2 hours. 2-Trimethylsilylethanol (0.19 ml, 1.32 mmol) was then added and the mixture was allowed to stir for a further 6 hours at 80° C. The mixture was concentrated in vacuo and the residue was dissolved in EtOAc, washed with 1M NaOH and then with water. The organic phase was separated, dried and evaporated in vacuo. The crude product was purified by flash chromatography eluting over a gradient of 0-5% MeOH in DCM. The product was obtained as a light brown oil (84 mg) after evaporation of the appropriate fractions. NMR (300 MHz, CDCl3) 8.70 (s, 1H), 8.16 (d, 1H), 7.54 (m, 2H), 7.21 (m, 1H), 6.66 (s, 1H), 4.98 (m, 1H), 4.22 (m, 2H), 3.25 (q, 2H), 1.69 (d, 6H), 1.38 (t, 3H), 1.01 (m, 2H).

Provenance & Evidence