A mixture of 4-((1-benzylpiperidin-3-yl)(hydrazono)methyl)-5-chloro-1H-pyrrolo[2,3-b]pyridine (1.04 g, 2.84 mmol), sodium tert-butoxide (0.652 g, 6.78 mmol), palladium acetate (0.0064 g, 0.028 mmol) and (R)-1-[(S)-2-(dicyclohexylphosphino)ferrocenyl]ethyl-di-tert-butyl phosphine (0.016 g, 0.028 mmol) in NMP (10 mL) was heated in the microwave at about 160° C. for about 30 min. Additional palladium acetate (0.0064 g, 0.028 mmol) and (R)-1-[(S)-2-(dicyclohexylphosphino)ferrocenyl]ethyl-di-tert-butyl phosphine (0.016 g, 0.028 mmol) were added and the mixture was heated in a microwave at about 160° C. for about 15 min. Additional palladium acetate (0.003 g, 0.014 mmol) and (R)-1-[(−2-(dicyclohexylphosphino)ferrocenyl]ethyl-di-tert-butyl phosphine (0.008 g, 0.014 mmol) were added and the mixture was again heated at about 160° C. for about 8 min. The solvent was removed under reduced pressure and the residue was partitioned between water (25 mL) and EtOAc (25 mL). The organic phase was washed with brine (20 mL), dried over anhydrous MgSO4, decolorized with charcoal and filtered. The solvent was removed under reduced pressure and the residue purified by silica gel chromatography, eluting first with DCM (1 L), a mixture of 98:1:1 DCM:TEA:MeOH (1 L) and then with a mixture of 97:1:2 DCM:TEA:MeOH (1 L) to yield 1-(1-benzylpiperidin-3-yl)-3,6-dihydropyrazolo[4,3-d]pyrrolo[2,3-b]pyridine (0.18 g, 0.54 mmol, 19%) as a brown solid: LC/MS (Table 2, Method a) Rt=1.36 min; MS m/z: 332 (M+H)+.
