Réaction #2482549

Équation de réaction

water

N-(1-tert-butyldimethylsilyloxy-2(R)-phenylethan-2-yl)-3-iodobenzamide

Lawesson's reagent

→

N-(1-tert-butyldimethylsilyloxy-2(R)-phenyl-ethan-2-yl)-3-iodobenzthiamide

Rendement 50.1%

Solvants

1,2-dimethoxyethane

Conditions de réaction

Traitement

1. 1
   workup.WAITat 60° C. for 2 hours
2. 2
   Températurecooled
3. 3
   ExtractionThe mixture was extracted with CH2 Cl2 (2×50 ml)
4. 4
   Lavagewashed with brine (100 ml)
5. 5
   Séchagedried (MgSO4)
6. 6
   Concentrationconcentrated under reduced pressure
7. 7
   AutreThe resulting residue was purified by column chromatography on silica gel eluting with ethyl acetate/hexane (=1:7)

Mode opératoire

To a solution of N-(1-tert-butyldimethylsilyloxy-2(R)-phenylethan-2-yl)-3-iodobenzamide (13.1 g, 27.2 mmol) in 1,2-dimethoxyethane (80 ml) was added Lawesson's reagent (8.2 g, 20 mmol). The reaction mixture was stirred at ambient temperature for 1 h and then at 60° C. for 2 hours, cooled and poured into water (100 ml). The mixture was extracted with CH2 Cl2 (2×50 ml), washed with brine (100 ml), dried (MgSO4) and concentrated under reduced pressure. The resulting residue was purified by column chromatography on silica gel eluting with ethyl acetate/hexane (=1:7) to afford N-(1-tert-butyldimethylsilyloxy-2(R)-phenyl-ethan-2-yl)-3-iodobenzthiamide (4.99 g, 50%) as a yellow liquid.

Source