Dimethylformamide → Pentyl methanesulfonate

Participants

Reaction Steps

To a stirred solution of 231 mg (5.79 mmol, 60% disp.) of NaH in 22 mL of DMF was added 2.05 g (4.45 mmol) of 5-(4′-hydroxyphenyl)-7-(dimethylamino)tetrahydrobenzothiepine-1,1-dioxide (obtained from Example 1402, Step 10), and the resulting solution was stirred at ambient temperature for 1 hour. To the mixture was added 18.02 g (55.63 mmol) of 1,5-dibromopentane and the solution was stirred overnight at ambient temperature. DMF was removed by high vacuum and the residue was extracted with ethyl acetate and washed with brine. The extract was dried over MgSO4, and the concentrated residue was purified by column chromatography to give the pentyl mesylate intermediate: 1H NMR (CDCl3) δ0.90(q, 6H), 1.05-2.0 (m, 17H), 2.2 (t, 1H), 2.8 (s, 6h), 3.0 (q, 2H), 3.22 (t, 2H), 3.95 (t, 2H), 4.1 (s, 1H), 5.42 (s, 1H), 6.1 (d, 1H), 6.6 (d, 1H), 6.9 (d, 2H), 7.4 (d, 2H), 7.9 (d, 1H).

Provenance & Evidence