Hydrochloric Acid → 4-[(4-(Hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-alpha,alpha-dimethylbenzeneacetic acid hydrochloride hydrate

Participants

Reaction Conditions

Reaction Steps

Mix ethyl 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-oxobutyl]-α,α-dimethylbenzeneacetate, hydrochloride (101.92 g, 0.1807 mol) and methanol (510 mL) and stir. Rapidly add 50% sodium hydroxide (72.27 g, 0.903 mol) and wash in with water (61 mL). Heat to reflux for 2 hours, allow to cool to 35° C. and treat with sodium borohydride (3.42 g, 0.0903 mol). Add water (100 mL) and maintain at 35° C. for 10 hours. Add 37% hydrochloric acid (53.0 g) to adjust pH to 11.5. Add acetone (26.5 mL) and water (102 mL). Hold at 35° C. for 2 hours and adjust to pH 2.5 with 37% hydrochloric acid (44.69 g). Dilute with water (408 mL), cool to −15° C., stir for 1.5 hours and collect the precipitate by vacuum filtration. Wash the filtercake with deionized water (3×100 mL) and vacuum dry to give 4-[4-[4-(hydroxydiphenylmethyl)-1-piperidinyl]-1-hydroxybutyl]-α,α-dimethylbenzeneacetic acid hydrochloride hydrate (97.10 g).

Provenance & Evidence