Cesium carbonate → 1-[4-(4-Biphenyl-2-ylmethyl-piperazin-1-yl)-benzyl]-3-methyl-1,3-dihydro-benzoimidazol-2-ylideneamine

Participants

Reaction Conditions

Reaction Steps

To a degassed solution of 1-(4-bromo-benzyl)-3-methyl-1,3-dihydro-benzoimidazol-2-ylideneamine (75 mg, 0.237 mmol) in anhydrous toluene (2 ml) was added Pd(OAc)2 (20 mg, 0.047 mmol). Nitrogen was bubbled through the suspension for 10 min before BINAP (29 mg, 0.047 mmol) was added. After a further 2 min 1-biphenyl-2-ylmethyl-piperazine (65 mg, 0.258 mmol) in degassed toluene (2 ml) was introduced and then after a additional 2 min Cs2CO3 (1.54 g, 4.75 mmol) was added and the reaction was stirred for 2 min. Throughout all of the additions nitrogen was continuously bubbled through the reaction mixture. The reaction was then sealed and heated to 95° C. where it was maintained for 16 h. After this time the dark red mixture was cooled to rt and filtered through Celite®. The collected solids were washed with additional toluene and then the combined filtrate and washings were concentrated under reduced pressure to give the crude product. Purification by preparative HPLC provided 1-[4-(4-biphenyl-2-ylmethyl-piperazin-1-yl)-benzyl]-3-methyl-1,3-dihydro-benzoimidazol-2-ylideneamine as a solid (14 mg, 12%). HPLC-MS 488 [M+1]+, 255.

Provenance & Evidence