反应步骤
_This reaction is done in triplicate_ : 6-bromo-1H-indazole (1.2 g, 6.09 mmol, 1 eq each), chloro(2-dicyclohexylphosphino-2',6'-di-i- propoxy-1,1'-biphenyl)[2-(2-aminoethylphenyl)]palladium(II), methyl-t- butylether adduct (RuPhos-PreCatalyst) (89 mg, 0.12 mmol, 0.02 eq each), 2-Dicyclohexylphosphino-2',6'-di-i-propoxy-1,1'-biphenyl (RuPhos ligand) (57 mg, 0.12 mmol, 0.02 eq, each) were taken a stoppered bottle, flush with N2, pyrrolidine (0.60 ml, 522 mg. 7.34 mmol, 1.2 eq, each) and lithium bis(trimethylsilyl)amide (1M soln in THF, 15 ml, 15 mmol, 2.46 eq, each) were added in succession, flushed with N2, stoppered the bottle and stirred at 60 °C. LC-MS, after 2 hrs, showed that all the starting material is consumed. Cooled to r.t, queched the reaction with 2M HCl (9 ml, each), combined the reaction mixture and then extracted with EtOAc (250 ml) and saturated NaHCO3 (aq) soln. The organics was collected and the aq. layer was further extracted with EtOAc (250 ml). The combined organics was further washed with brine (250 ml). The organics was collected, dried (Na2SO4), filtered and evaporated to a brown solid (4.01 g, combined crude yield). The residue was chroamtographed (SiO2 - 100 g, Biotage-Pre-packed colum, heptane-EtOAC 5:1 to 2:1 gradiant. The appropriate fractions were combined and evaporated to a light brown solids (TLC: Rf = 15 mm/63 mm, heptane-EtOAc 1:1, _compound in TLC plate beome grey colored upon standing for few minutes_ ) corresponds to the required product (P1) (Starting material comes at 28 mm/63 mm in the same solvent system). _EN07765-42-01 (SN1050263564; AZ13824296-001_ ): 3.207 g (total yield, so each batch should be 1.069 g, 94%, ca 96% pure). 1H NMR (500 MHz, DMSO) d 1.94 - 2 (m, 4H), 3.27 (t, 4H), 6.34 (s, 1H), 6.56 (dd, 1H), 7.50 (d, 1H), 7.78 (s, 1H), 12.35 (s, 1H). Expected Number of Hs: 13. Assigned Hs: 13. LC-MS: ESI-MS m/z: [M+H]\+ 188.2. Rf = 1.59 min/4 min and 1.48 min/4 min in acidic (pH3) and basic (pH10) system repectively. TLC: Rf = 15 mm/64 mm (SiO2-glas plate, heptane-EtOAc 1:1 v/v, spots were detected by UV254 ( _spot became grey colored upon standing the plate at r.t_.)
