1,4-Bis(diphenylphosphino)butane → HCID 89610333, compound

Participants

Reaction Steps

A mixture of 4.26 g (15 mmol) triflate (6.1b), 2.47 g (18 mmol) of 1-prop-2-ynyl-pyrrolidine-2,5-dione (7.4), 0.067 g (0.3 mmol) of [(C6H5)3P]2PdCl2, 0.143 g (0.75 mmol) CuI, 0.32 g (0.75 mmol) of 1,4-bis(diphenyl-phosphino)butane and 7 ml (50.5 mmol) of TEA in 40 ml DMF under nitrogen at 100° C. for 3 h. The inorganic salts are removed and DMF is evaporated. The residue is treated with water, extracted 3×50 ml of EtOAc, the collected organic phase is evaporated and purified by flash chromatography (toluene-MeOH 9:1). The desired intermediate 4.19 is 1.9 g (44%) of 4-[3-(2,5-dioxo-pyrrolidin-1-yl)-prop-1-ynyl]-3-methoxy-benzaldehyde, as a dark yellow solid. (M+H)+=272, Rt=2.15 min (A), purity: 98.9%.

Provenance & Evidence