2-(4-Bromophenyl)-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaborine

• 2-(4-Bromophenyl)-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaborine [B3655]
• 4-(Ethoxycarbonyl)phenylboronic Acid (contains varying amounts of Anhydride) [E0868]
• Tetrakis(triphenylphosphine)palladium(0) (= Pd(PPh₃)₄) [T1350]
• Potassium Carbonate [P1748]
• Toluene
• Water

To a reaction vessel, 2-(4-bromophenyl)-2,3-dihydro-1H-naphtho[1,8-de][1,3,2]diazaborine (3.0 g, 9.3 mmol), 4-(ethoxycarbonyl)phenylboronic acid (2.7 g, 4.0 mmol), Pd(PPh₃)₄ (0.54 g, 0.47 mmol), potassium carbonate (3.9 g, 28.0 mmol), toluene (30 mL), ion-exchange water (15 mL) were subsequently added and heated at 90 °C. After the consumption of the starting material, the reaction mixture was cooled to room temperature. Dichloromethane was added and aqueous layer was removed. The organic layer was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated to obtain crude product. The crude was dissolved in dichloromethane and passed through a pad of silica gel and concentrated. The residue was washed with hexane to give 1 (2.5 g, yield. 69%) as a pale yellow powder.

The reaction mixture was monitored by TLC (hexane:ethyl acetate = 4:1, Rf = 0.5).

¹H NMR (400 MHz, CDCl₃); δ 8.17-8.10 (m, 2H), 7.80-7.65 (m, 6H), 7.16 (dd, 2H, J = 7.3, 8.2 Hz), 7.8 (dd, 2H, J = 7.3, 8.2 Hz), 6.45 (dd, 2H, J = 0.8, 7.3 Hz), 6.08 (brs, 2H), 4.42 (q, 2H, J = 7.2 Hz), 1.43 (t, 3H, J = 7.2 Hz).

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• Tailoring porosity and rotational dynamics in a series of octacarboxylate metal-organic frameworks
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