Triethylamine → (+/-)-2-methyl-cyclohexanecarboxylic acid-N'-[5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-hydrazide

Participants

Reaction Conditions

Reaction Steps

A flask containing a mixture of [5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-hydrazine hydrochloride (336 mg, 1.06 mmol) and (+/−)-2-methyl-1-cyclohexane-carboxylic acid (0.18 mL, 1.22 mmol) in dry dichloromethane (11 mL) was cooled to 0° C. (ice bath) under nitrogen atmosphere. To this cooled mixture was added triethylamine (0.31 mL, 2.1 mmol) and EDCI (278 mg, 1.45 mmol). After 30 minutes the cooling bath was removed and the material was stirred for 3 hours. An aqueous solution of 5% sodium bicarbonate (40 mL) and methylene chloride (30 mL) were added and the mixture was shaken in a reparatory funnel. The organic phase was collected and washed with brine (40 mL). The aqueous phases were back extracted with methylene chloride (2×30 mL). The organic phases were combined, dried (MgSO4), filtered and stripped. The crude remainder was purified by preparative TLC, using 45% ethyl acetate in hexanes to elute. The product band was collected, affording 152 mg of (+/−)-2-methyl-cyclohexanecarboxylic acid-N′-[5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl]-hydrazide as a golden brown oil, which solidified on standing. MS (M+H)+=404.

Provenance & Evidence