4-Toluenesulfonyl chloride → (7-Nitro-2,3-dihydrobenzo[b][1,4]dioxin-2-yl)methyl 4-methylbenzenesulfonate

Participants

Reaction Conditions

Reaction Steps

A 500 mL round bottomed flask equipped with a magnetic stir bar is charged with [7-nitro-2,3-dihydro-1,4-benzodioxin-2-yl]methanol (37.3 g, 177 mmol) and anhydrous pyridine (150 mL). The solution is cooled to 5° C. and p-toluenesulfonyl chloride (42.1 g, 221 mmol) is added in one portion. After 1 h, the cooling bath is removed, and the solution is stirred for another 3 h. The reaction mixture is poured into a rapidly stirred flack containing water (750 mL). The precipitate is collected by vacuum filtration, and the filter cake is rinsed with water and suction dried to give the title compound (63.8 g, 99%) as yellow granules. LCMS (Standard Method): 2.81 min, 388 (M+Na)+. 1H NMR (300 MHz, DMSO-d6) δ7.79-7.72 (m, 3H), 7.49-7.42 (m, 3H), 7.06 (d, J=8.8 Hz, 1H), 4.59-4.55 (m, 1H), 4.41 (dd, J=2.6, 11.6 Hz, 2H), 4.22 (dd, J=6.3, 11.5 Hz, 1H), 4.12 (dd, J=6.8, 11.7 Hz, 1H), 2.38 (s, 3H).

Provenance & Evidence