A suspension of tert-butyl 4-(3-(8-bromo-N-methyl-4,5-dihydrobenzo[b]thieno[2,3-d]oxepine-2-carboxamido)-4-chlorobenzoyl)piperazine-1-carboxylate (500 mg, 0.76 mmol), Pd(OAc)2 (9 mg, 0.038 mmol), Xantphos (44 mg, 0.076 mmol), MeNH2.HCl (77 mg, 1.14 mmol) and Na2CO3 (242 mg, 2.28 mmol) in toluene (10 mL) was heated at 80° C. under atmosphere of CO from balloon for overnight. Then it was filtrated and concentrated, the crude product was purified by pre-TLC (DCM/MeOH=10:1 as eluted solvent) to give tert-butyl 4-(4-chloro-3-(N-methyl-8-(methylcarbamoyl)-4,5-dihydrobenzo[b]thieno[2,3-d]oxepine-2-carboxamido)benzoyl)piperazine-1-carboxylate (390 mg, yield: 80%). 1H NMR (DMSO, 400 MHz): δ7.59-7.26 (m, 8H, ArH, NH), 4.26 (t, J=5.2 Hz, 2H, CH2), 3.57-2.80 (m, 18H, CH2, CH3), 1.47 (s, 9H, CH3)
