Reaction #1256710

Reaction equation

triflate

trifluoromethanesulfonic acid 4-(3,5-dimethyl-pyridin-4-yl)-3,5-dimethyl-phenyl ester

Cs2CO3

benzophenone imine

→

title compound

Yield 97.7%

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

Yield 97.7%

Solvents

THF

Conditions

Workup

1. 1
   OtherThe tube was evacuated
2. 2
   OtherThe Schlenk tube was sealed
3. 3
   Otherthe mixture was degassed by three freeze-thaw cycles
4. 4
   workup.STIRRINGThe mixture was then stirred at 65° C. for 15 h
5. 5
   workup.ADDITIONdiluted with methylene chloride (40 mL)
6. 6
   Filtrationfiltered
7. 7
   Concentrationthe filtrate was concentrated in vacuo
8. 8
   OtherThe resulting yellow solid was purified by flash chromatography on silica gel
9. 9
   Washeluting with 1:1 hexane

Procedure

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.

Source