Phosphine → HCID 66869321, compound

Participants

Reaction Steps

Potassium phosphate (2.65 g, 12.47 mmol) is dried at 120° C. under high vacuum for 45 minutes. After cooling to RT and venting with dry argon, palladium dibenzylideneacetone (Pd2(dba)3, 25 mg, 0.03 mmol) and di-tert-butylphosphino pentaphenylferrocene (39 mg, 0.06 mmol) are added. (2-Chloro-pyridin-4-yl)-acetic acid tert-butyl ester (631 mg, 2.77 mmol), dissolved in 1,2-dimethoxyethane (14 ml, dried by passing through a column of basic aluminum oxide), and 1-methyl piperazine (830 mg, 8.31 mmol) are added. The reaction mixture is warmed to 40° C. for 1 h. Additional Pd2(dba)3 (25 mg, 0.03 mmol) and phosphine ligand (39 mg, 0.06 mmol) is added, and stirring is continued at 60° C. for 2 h. Additional Pd2(dba)3 (25 mg, 0.03 mmol) and phosphine ligand (39 mg, 0.06 mmol) is added, and stirring is continued at 90° C. for 18 h and at RT for 72 h. TLC and MS analysis indicated the presence of desired product. The reaction mixture is diluted with EtOAc and poured into a saturated solution of NaCl in water. The organic layer is separated, dried over Na2SO4, and the solvent is evaporated. Purification of the residue by FCC (hexane/EtOAc, gradient from 95:5 to 90:10) affords the title compound. 1H NMR (CDCl3, 400 MHz): δ 1.44 (s, 9H), 2.34 (s, 3H), 2.52 (m, 4H), 3.42 (s, 2H), 3.55 (m, 4H), 6.55 (d, J=4 Hz, 1H), 6.56 (s, 1H), 8.11 (d, J=4 Hz, 1H). ES+−MS: 292.4 [M+H]+.

Provenance & Evidence