Reaction #6088

Reaction equation

2,3,4-tri-O-acetyl-5-thio-D-xylopyranosyl bromide

4-mercaptobenzonitrile

→

expected product

Yield 17.0%

4-cyanophenyl 2,3,4-tri-O-acetyl-1,5-dithio-β-D-xylopyranoside

Yield 17.0%

Solvents

acetonitrile

Conditions

Workup

1. 1
   Filtrationthe reaction mixture is filtered on Celite® in ethyl acetate
2. 2
   WashThe filtrate is washed with a 1N solution of hydrochloric acid, water
3. 3
   Dryinga 1N solution of sodium hydroxide, water and finally a saturated solution of sodium chloride, dried over magnesium sulfate
4. 4
   Otherevaporated under reduced pressure
5. 5
   OtherAfter purification by chromatography on silica gel using a hexane/ethyl acetate mixture (3/1 v/v)
6. 6
   Otheras the eluent, and precipitation in ether

Procedure

A suspension of 625 mg (1.76.10-3 mol) of 2,3,4-tri-O-acetyl-5-thio-D-xylopyranosyl bromide, 200 mg (1.48.10-3 mol) of 4-mercaptobenzonitrile and a 400 pm molecular sieve in 10 ml of acetonitrile is stirred in the presence of 605 mg (4.4.10-3 mol) of zinc chloride and 310 mg (1.8.10-3 mol) of silver imidazolate, in the absence of light, under an inert atmosphere. After heating at 50° C. for 3 h, the reaction mixture is filtered on Celite® in ethyl acetate. The filtrate is washed with a 1N solution of hydrochloric acid, water, a 1N solution of sodium hydroxide, water and finally a saturated solution of sodium chloride, dried over magnesium sulfate and evaporated under reduced pressure. After purification by chromatography on silica gel using a hexane/ethyl acetate mixture (3/1 v/v) as the eluent, and precipitation in ether, 100 mg (yield: 17%) of the expected product are obtained.

Source