Diisopropylethylamine → (+/-)-1-[3-(Benzhydrylidene-amino)-4-cyano-benzyl]-4-(6-chloro-benzo[b]thiophene-2-sulfonyl)-6-oxo-piperazine-2-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A solution containing (±)-1-[3-(benzhydrylidene-amino)-4-cyano-benzyl]-6-oxo-piperazine-2-carboxylic acid methyl ester (55 mg, 0.12 mmol) in CH2Cl2 (1 mL) is cooled to 0° C. DIPEA (24 mg, 0.18 mmol) is then added followed by the addition of 6-chloro-benzo[b]thiophene-2-sulfonyl chloride (32 mg, 0.12 mmol), EXAMPLE 1. The reaction mixture is warmed to ambient temperature. After 16 h, the reaction mixture is absorbed directly onto silica gel and chromatographed (CH2Cl2 to 2% MeOH/CH2Cl2) to provide 60 mg (73%) of the title compound. 1H NMR (300 MHz, CDCl3) δ2.77 (dd, J=12.3, 3.4 Hz, 1H), 3.50-3.72 (m, 3H), 3.79 (s, 3H), 4.15 (dd, J=12.3, 1.4 Hz, 1H), 4.24 (d, J=16.9 Hz, 1H), 5.41 (d, J=15.3 Hz, 1H), 6.50 (s, 1H), 6.76 (dd, J=7.9, 1.4 Hz, 1H), 7.11-7.86 (m, 15H) ppm; MS (ISP loop): m/z 683 (M+H).

Provenance & Evidence