Water ethanol → 1-[(S)-4-(2,3-Dihydro-[1,4]dioxino[2,3-b]pyridin-3-yl)-benzyl]-piperidine-4-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 1-[(8)-4-(2,3-dihydro-[1,4]dioxino[2,3-b]pyridin-3-yl)-benzyl]-piperidine-4-carboxylic acid ethyl ester (prepared from Intermediate C and piperidine-4-carboxylic acid ethyl ester according to General Method F) (3.00 g, 7.90 mmol) in 4:1 EtOH/water (80 mL) is added LiOH monohydrate (0.994 g, 23.7 mmol) and the reaction stirred overnight at about 25° C. The reaction is concentrated, diluted with water and washed with Et2O (2×). The aqueous layer is lypholized to dryness then purified by silica gel chromatography eluting with 20% (2M NH3 in MeOH)/DCM. The pooled fractions are concentrated and dried to provide the title compound (K) as a foamed solid.

Provenance & Evidence