“…Coupling of 4-N,N-dimethyl-aminophenylethyne [13,14] (1.2 equiv.) with 2 (373 mg, 1 mmol) according to the general procedure B (t = 24 hours) gave after purification by column chromatography (silica gel, eluent: petroleum ether:ethyl acetate (7:3)) 274 mg (79%) of 15 as a yellow solid, mp >250°C; ir : 3177, 2201, 1673, 1607, 1586, 1558, 1520, 1462, 1391, 1359, 1222, 1151, 1115, 810 ,72.81;N,16.17;H,6.40.…”