Cesium carbonate → 4-(3,5-dimethylpyridin-4-yl)-N-(diphenylmethylene)-3,5-dimethyl-benzenamine

Participants

Reaction Steps

A flame-dried sealable Schlenk tube was charged with triflate 8 (0.359 g, 1.00 mmol), Cs2CO3 (0.456 g, 1.40 mmol), Pd(OAc)2 (6.7 mg, 0.030 mmol), and BINAP (28.2 mg, 0.0450 mmol). The tube was evacuated and then backfilled with N2. Next, a solution of benzophenone imine (0.224 g, 1.20 mmol) in dry THF (4 mL) was added with stirring under an N2 flow. The Schlenk tube was sealed, the mixture was degassed by three freeze-thaw cycles, and backfilled with N2. The mixture was then stirred at 65° C. for 15 h. The reaction mixture was next cooled to room temperature, diluted with methylene chloride (40 mL), filtered, and the filtrate was concentrated in vacuo. The resulting yellow solid was purified by flash chromatography on silica gel, eluting with 1:1 hexane:ethyl acetate, to give 0.381 g (97.7%) of the title compound as a colorless solid: mp 44-45° C.; 1H NMR (400 MHz, CD2Cl2): δ 8.305 (s, 2H), 7.774 (d, 2H, J=8.0 Hz), 7.494-7.408 (m, 3H), 7.271 (m, 3H), 7.144 (d, 2H, J=6.8 Hz), 6.476 (s, 2H), 1.828 (s, 6H), 1.706 (s, 6H); 13C NMR (100 MHz, CD2Cl2): δ 168.647, 151.523, 148.783, 148.611, 140.013, 136.737, 135.099, 132.206, 131.678, 131.114, 130.040, 129.685, 128.912, 128.583, 128.038, 120.459, 19.842, 16.594; MS (ESI): m/z 391.5 [(M+H)+, 100]; Anal. Calcd. for C28H26N2: C, 86.12; H, 6.71; N, 7.17. Found; C, 85.86; H, 6.74; N, 7.17.

Provenance & Evidence