Diethyl Ether → 1,5-Dihydro-benzo[e][1,3,2]dioxathiepine 3,3-dioxide

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of 1,2-benzenedimethanol (2.00 g, 14.5 mmol) and triethylamine (8.08 mL, 58.0 mmol) in 50 mL of CH2Cl2 was added thionyl chloride (1.59 mL, 21.7 mmol) dropwise at 0° C. The resulting dark brown solution was stirred at 0° C. for 1 h. Then 30 mL of brine was added. The organic layer was separated and the aqueous layer was extracted with CH2Cl2 (20 mL) once. The combined organic layers were dried with Na2SO4 and evaporated. The residue was further dried on vacuum pump for 2 h to afford crude cyclic sulfite (2.48 g. 13.5 mmol). This crude cyclic sulfite was dissolved in a mixture of acetonenitrile, chloroform and water (20, 20, 30 mL respectively). NalO4 (4.33 g, 20.3 mmol) and RuCl2.xH2O (60 mg) were added at 0° C. The resulting reaction mixture was vigorously stirred at 0° C. for 1 h. 30 mL of brine was added, followed by 60 mL of Et2O. The aqueous layer was extracted with Et2O (30 mL×2). The combined organic layers were dried with Na2SO4 and evaporated. The resulting solid residue was purified by passing through a short silica gel plug (CH2Cl2 as eluent) to give 40 as a white solid (2.55 g, 88%).

Herkunft & Nachweise