To N-(4-bromo-2-nitro-phenyl)-N,N′,N′-trimethyl-propane-1,3-diamine (940 mg, 2.97 mmol), Pd(PhCN)2Cl2 (34 mg, 0.09 mmol), CuI (11 mg, 0.06 mmol) and dioxane (4 mL) was added P(tBu)3.HBF4 (53 mg, 0.18 mmol), iPr2NH (0.50 mL, 3.6 mmol) and (trimethylsilyl)acetylene (0.49 mL, 3.6 mmol). The mixture was stirred for 3.5 h at RT, diluted with MeOH and stirred at RT with excess saturated aqueous K2CO3 for 2 h. The mixture was filtered through a pad of activated charcoal and concentrated to yield N-(4-ethynyl-2-nitro-phenyl)-N,N′,N′-trimethyl-propane-1,3-diamine. MS m/z=262 [M+1]+. Calc'd for C14H19N3O2: 261.33.
