Hydrochloric Acid → N-Boc-3-mesyloxypiperidine

Participants

Reaction Conditions

Reaction Steps

To a solution of 216 g of N-BOC-3(R,S)-hydroxypiperidine in 5 l of CH2Cl2 222 ml of triethylamine are added at 0-5° C. 137 g of methanesulfonyl chloride in 300 ml of CH2Cl2 are added dropwise over a period of 45 min, maintaining the temperature at 0-5° C. After additional stirring for 70 minutes 2 l of deionised water are added and the pH is adjusted to 5.9 by addition of about 90 ml of 2 n HCl. The aqueous phase is separated and the organic phase is washed with water. The solution is evaporated to dryness and 270-280 g of an oily residue are obtained. After treating with 1 l of n-heptane crystallization occurs. Crystals are isolated and dried in vacuo. 250 g of N-BOC-3(R,S)-methylsulfonyloxy-piperidine are obtained.

Provenance & Evidence