Formic Acid → 2-(3-Pyridinylmethyl)-3-quinuclidinol

Participants

Reaction Conditions

Reaction Steps

0.518 g (2.39 mmol) of racemic 2-(3-pyridinylmethyl)-3-quinuclidinone, 0.65 ml (4.66 mmol) of triethylamine, 0.44 ml (11.7 mmol) of formic acid (formic acid/triethylamine=5/2 to the substrate molar ratio), 5.5 mg (8.6×10−3 mmol, S/C=200) of RuCl [(S,S)— TsDPEN] (p-cymene) were introduced into a 20 mL Schlenk flask under an argon atmosphere and stirred for 19 hours at 40° C. The reaction liquid was diluted in dichloromethane, neutralized by potassium carbonate, and after removing the solids by filtration, the target substance was obtained with a yield of 49% by concentrating and drying to solids. By NMR spectroscopy it was confirmed that 2-(3-pyridinylmethyl)-3-quinuclidinol of only one of the diastereomers was obtained. The optical purity, determined by HPLC analysis (Daicel Chiralcel OD-H two columns connected in series, Hexane/2-propanol/diethylamine=80/20/0.1, 0.3 mL/min., 25° C., the retention times of the two types of optical isomers in the diastereomer obtained were 64.0 min. and 83.2 min.) was 85% ee.

Provenance & Evidence