Reaction #989

Reaction equation

(R)-N-(2-pyridyl)-2-aminopropanol

N,N-diisopropylethylamine

thionyl chloride

→

(R)-4-methyl-3-(2-pyridyl)-[1,2,3] oxathiazolidine 2-oxide

Solvents

dichloromethane

dichloromethane

Conditions

Workup

1. 1
   Otherwas kept below 10° C
2. 2
   OtherThe organic phase was separated
3. 3
   Washwashed with water (5×500 ml)
4. 4
   ExtractionThe aqueous phase was back-extracted with dichloromethane (2×500 ml)
5. 5
   Dryingdried (MgSO4)
6. 6
   Otherevaporated in vacuo
7. 7
   Otherto give a brown oil
8. 8
   OtherThis was purified on a silica column
9. 9
   Washeluting with diethyl ether

Procedure

A solution of (R)-N-(2-pyridyl)-2-aminopropanol (20.0 g, 0.13 moles) and N,N-diisopropylethylamine (33.6 g, 0.13 moles) in dichloromethane (500 ml) was cooled to 5° C. Then thionyl chloride (15.5 g, 0.13 moles) in dichloromethane (100 ml) was added slowly whilst the temperature was kept below 10° C. The mixture was stirred for 0.5 h. and ice cold water (500 ml) was added. The organic phase was separated and washed with water (5×500 ml). The aqueous phase was back-extracted with dichloromethane (2×500 ml), the organic phases were combined, dried (MgSO4) and evaporated in vacuo to give a brown oil. This was purified on a silica column, eluting with diethyl ether to give (R)-4-methyl-3-(2-pyridyl)-[1,2,3] oxathiazolidine 2-oxide (154.4 g) as a clear oil.

Source