Binap, (A+-)- → 3-[4-(4-Biphenyl-2-ylmethyl-piperazin-1-yl)-benzyl]-1-[3-(4-fluoro-phenoxy)-propyl]-5-methyl-1,3-dihydro-benzoimidazol-2-ylideneamine

Participants

Reaction Conditions

Reaction Steps

3-(4-Bromo-benzyl)-1-[3-(4-fluoro-phenoxy)-propyl]-5-methyl-1,3-dihydrobenzoimidazol-2-ylideneamine, hydrobromide salt (20 mg, 0.036 mmol) was partitioned between aqueous NaOH and EtOAc. The organic phase was separated, dried (Na2SO4) and concentrated under reduced pressure to provide 3-(4-bromo-benzyl)-1-[3-(4-fluoro-phenoxy)-propyl]-5-methyl-1,3-dihydrobenzoimidazol-2-ylideneamine (0.036 mmol). To a degassed solution of Pd(OAc)2 (0.04 mg, 0.16 □mol) and BINAP (0.44 mg, 0.71 mmol) in toluene (8 ml) at 40° C. was added 1-biphenyl-2-ylmethyl-piperazine (18 mg, 0.071 mmol) followed by 3-(4-bromo-benzyl)-1-[3-(4-fluoro-phenoxy)-propyl]-5-methyl-1,3-dihydrobenzoimidazol-2-ylideneamine (0.036 mmol) and sodium t-butoxide (4.8 mg, 0.05 mmol). The suspension was then heated to 130° C. where it was maintained for 20 h. After this time, the mixture was filtered and then the filtrate was partitioned between H2O and EtOAc. The organic phase was separated and concentrated under reduced pressure to provide the crude product. Purification by preparative HPLC gave 3-[4-(4-biphenyl-2-ylmethyl-piperazin-1-yl)-benzyl]-1-[3-(4-fluoro-phenoxy)-propyl]-5-methyl-1,3-dihydro-benzoimidazol-2-ylideneamine (2.5 mg, 11%). HPLC-MS 640 [M+1]+, 320 (100%).

Provenance & Evidence