Dimethyl Sulfoxide → HCID 86739365, compound

Participants

Reaction Steps

A solution of crude 2 (66.6 g, 99.4 mmole) in CH2Cl2 (250 mL) was added dropwise under argon to a mixture prepared from DMSO (14.2 mL, 200 mmole) in CH2Cl2 (100 mL) and TFAA (21.2 mL, 150 mmole) in CH2Cl2 (70 mL) as reported above for 6. The mixture was stirred in the dry ice acetone bath for 90 min. TEA (40 mL) was added and the mixture then allowed to warm to room temperature. The solution was evaporated, the residue dissolved in CHCl3 and washed 3 times with dilute NH4OH. Evaporation of the dried organic phase gave a foam which crystallized from 95% ethanol to give 53.8 g (81%) of 10 as white crystals, mp 150°-153° C. Recrystallization from 95% ethanol gave analytically pure 10, mp 155°-156° C.; NMR δ 7.2-7.9 (m, 811, tosyl 11's); 7.70 (s, 2H, H1 and H2); 4.47 (s, H5).

Provenance & Evidence