Triphenylphosphine → 3-[(Tert-butyldimethylsilyloxy)methyl]-6-[(2-chloro-5-trifluoromethyl-phenyloxy)methyl]-1,2-dithiin

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of 3-(hydroxymethyl)-6-[(tert-butyldimethylsilyloxy)methyl]-1,2-dithiin (U.S. Ser. No. 08/212,096) (200 mg, 0.688 mmol) in 5 mL dry THF was added a solution of 2-chloro-5-(trifluoromethyl) phenol (271 mg, 180 μL, 1.38 mmol) in 5 mL of THF, followed by the addition of triphenylphosphine (220 mg, 0.83 mmol). The resulting solution was cooled to 0° C., then 140 μL (155 mg, 0.89 mmol) of diethylazodicarboxylate was added, and the reaction mixture was kept at 0°-5° C. for 30 min and then the ice-water bath was removed. The reaction mixture was stirred at rt for 17 h. For isolation of the products the reaction mixture was chromatographed directly on a silica gel column, using ethyl acetate-hexane (1:3) as eluant, to yield 3-[(tert-butyldimethylsilyloxy)methyl]-6-[(2-chloro-5-trifluoromethyl-phenyloxy)methyl]-1,2-dithiin, 200 mg (62%); 1H NMR(CDCl3):δ7.54 (d, J=8, 1 H), 7.23 (d, J=8.4, 1 H), 7.16 (s, 1 H), 6.54 (d, J=6.4, 1 H), 6.42(d, J=6.4, 1 H), 4.78(s, 2 H), 4.31 (s, 2 H), 0.9 (s, 9 H), 0.1 (s, 6 H); MS (EI):m/z 468.1.

Provenance & Evidence