Triethylamine → 1-(1-tert-butoxycarbonyl-4-piperidylacetyl)-4-mesyloxypiperidine

Participants

Reaction Steps

To 16.3 g (0.05 mol) of 1-(1-tert-butoxycarbonyl-4-piperidylacetyl)-4-hydroxypiperidine [5], 147.1 g of toluene and 6.58 g (0.065 mol) of triethylamine were added. 6.30 g (0.055 mol) of mesyl chloride was added dropwise to the mixture at a temperature in the range of 0 to 5° C. and the reaction was allowed to proceed for 2 hours at the temperature in the range. Toluene was added to the reaction mixture. Thereafter, the reaction mixture was washed with an aqueous solution of sodium hydrogencarbonate and an aqueous solution of sodium chloride, and concentrated under a reduced pressure. 70.8 g of toluene was added to the concentrated residue, and the temperature of the mixture was increased. After the residue was dissolved in toluene, filtration was carried out. Thereafter, the filtrate was cooled to room temperature and the crystals which precipitated at room temperature were collected by filtration. The resultant wet crystals were dried under a reduced pressure, whereby 17.2 g of the title compound in the state of white crystalline powder was obtained (the yield was 84.8%). The values obtained by the analysis of 1HNMR, 13CNMR and mass spectroscopy were substantially the same as those obtained in Step 5a of Example 2.

Provenance & Evidence