反应详情

A mixture of (E)-2-[2-(tetrahydro-pyran-4-yl)-vinyl]-5-(2-trifluoromethyl-phenyl)-1H-benzimidazole (0.220 g, 0.591 mmol, prepared as in STEP D above) in EtOH (4 mL) was treated with 5M HCl in i-PrOH (130 μL, 0.650 mmol) at room temperature for 1 h and concentrated in vacuo. The residue was taken up in a minimum amount of EtOH (2 mL). Hexane was added with stirring until the mixture became cloudy. EtOH (1 mL) was added, and hexane was very slowly added until precipitate formed. The resulting mixture was cooled in the refrigerator for 45 min. The solid was filtered, washed with cold hexane, and air-dried to yield (E)-2-[2-(tetrahydro-pyran-4-yl)-vinyl]-5-(2-trifluoromethyl-phenyl)-1H-benzimidazole hydrochloride as an off-white solid.

1. concentrationconcentrated in vacuo
2. additionHexane was added
3. additionEtOH (1 mL) was added
4. additionhexane was very slowly added until precipitate
5. customformed
6. temperatureThe resulting mixture was cooled in the refrigerator for 45 min
7. filtrationThe solid was filtered
8. washwashed with cold hexane
9. customair-dried