Reaktion #6634

Reaktionsgleichung

S-(4-bromophenyl) 3,3-dimethyl-thioacrylate

aluminum chloride

Compound 69

S-(4-bromophenyl) 3,3-dimethyl-thioacrylate

→

title compound

4,4-Dimethyl-6-bromo-2-oxo-thiochroman

Lösungsmittel

methylene chloride

brine

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturTo a stirred, ice-cooled
2. 2
   workup.ADDITIONwas added under nitrogen
3. 3
   ExtraktionThe mixture was extracted with methylene chloride
4. 4
   Waschenthe combined organic extracts were washed with saturated NaCl solution
5. 5
   Trocknendried (MgSO4)
6. 6
   SonstigeThe solvent was removed in vacuo
7. 7
   Sonstigethe residue recrystallized from hexanes

Vorschrift

To a stirred, ice-cooled suspension of 15.9 g (119 mmol) of aluminum chloride in 140 ml of methylene chloride was added under nitrogen, a solution of 21.64 g (79.9 mmol) of S-(4-bromophenyl) 3,3-dimethyl-thioacrylate (Compound 69) in 100 ml of methylene chloride. The mixture was then stirred at room temperature for 72 h and then poured into 250 g of an ice and brine mixture. The mixture was extracted with methylene chloride and the combined organic extracts were washed with saturated NaCl solution and then dried (MgSO4). The solvent was removed in vacuo and the residue recrystallized from hexanes to give the title compound as white crystals. PMR (CDCl3): δ 1.40 (6H, s), 2.67 (2H, s), 7.31-7.40 (3H, m). MS exact mass, m/e 269.9714 (calcd. for C11H11SOBr, 269.9714).

Quelle