In a 1 L 3-neck RBF equipped with magnetic stir bar, condenser, thermocouple, and N2 inlet, crude (E)-5,7-dichloro-1-methyl-1H-benzo[e][1,4]diazepin-2(3H)-one (30 g, 0.124 mol) was dissolved into 300 mL of DME. To this was added a solution of Na2CO3 (21 g, 0.2 mol in 200 mL of H2O) followed by addition of 4-methoxyphenyl boronic acid (22 g, 0.145 mol) and Pd(PPh3)4 (1.2 g, 8.3 mmol). The reaction mixture was heated in a 85° C. oil bath, under N2, for 2 h and then cool to room temp. To this was added 200 mL of EtOAc and the mixture stirred for 5 min. The organic layer was separated and washed with H2O (200 mL) and brine (200 mL). Organic layer was dried over MgSO4 and then concentrated to dryness to give 53 g of crude product. This was subjected to silica chromatography using 210 g of silica gel and EtOAc/hepatene (12:88 to 30:70 to 50:50 to 70:30; total of 8 L mobile phase). Fractions containing pure product were combined and concentrated to dryness to give 42.7 g of pure product (quantitative). 1H NMR (300 MHz, CDCl3) δ 3.38 (s, 3H), 3.73 (d, 1H), 3.85 (s, 3H), 4.75 (d, 1H), 6.9 (m, 2H), 7.31 (m, 2H), 7.48-7.58 (m, 3H).
