Compound 1b

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Compound data: 1H NMR

Compound data: 13C NMR

Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

(1,1':3',1''-terphen-5'-yl)magnesium bromide was prepared from 5'-bromo-1,1':3',1''-terphenyl (13.0 g, 42 mmol) and magnesium turnings (6.0 g) activated by 1,2-dibromoethane in diethyl ether (100 mL) at room temperature. The solution of the Grignard reagent was cannulated into a solution of N-methylphthalimide (1.13 g, 7.0 mmol) in toluene (50 mL) at room temperature. The mixture was heated in an oil bath at 120 °C, and concentrated until the volume was reduced to ca. 50 mL. Then, the Schlenk flask was sealed and stirred at 120 °C for 1 day. After cooling to room temperature, the reaction mixture was quenched by addition of a saturated aqueous NH₄Cl solution, and extracted by using DCM (3 x 50 mL). The combined organic phase was dried over MgSO₄, filtered, evaporated to dryness, and the residue was purified by flash silica-gel column chromatography (hexane/EtOAc = 97/3 to 90/10). The obtained crude 1b was triturated with hot hexane (ca. 100 mL), cooled to room temperature, filtered, and the solid was dried in vacuo at 120 °C overnight. Compound 1b was obtained as a colourless solid (2.48 g, 2.37 mmol, 34% yield). mp: 284–286 °C (decomp.); TLC (hexane: ethyl acetate, 90:10 v/v): R_f = 0.30; ¹H NMR (800 MHz, CDCl₃) δ 7.68 (s, 4H), 7.48–7.43 (m, 10H), 7.41 (d, J = 7.4 Hz, 16H), 7.36–7.24 (m, 24H), 2.90 (s, 3H); ¹³C NMR (201 MHz, CDCl₃) δ 146.0 (4C, 4°), 145.3 (2C, 4°), 141.3 (8C, 4°), 141.2 (8C, 4°), 128.8 (16C, 3°), 128.0 (2C, 3°), 127.3 (24C, 3°), 127.0 (8C, 3°), 125.1 (2C, 3°), 125.0 (4C, 3°), 80.3 (2C, 4°), 29.3 (1C, N-CH₃); HRMS (m/z): [M+H]⁺ calcd. for C₈₁H₅₈N, 1046.4720; found, 1046.4711.