Yield:316-69-8 82%

Reaction Conditions:

with chlorosulfonic acid at 20; for 0.5 h;

Steps:

11 4-Fluoro-naphthalene-1-sulfonyl chloride (27)

1-Fluoronaphthalene (20.0 g, 0.14 mol) was added in small portions to a stirred solution of chlrosulfonic acid (79 g, 45 mL, 0.68 mol) at room temperature. The reaction was stirred for 30 minutes until gas evolution ceased. The reaction mixture was poured carefully over a mixture of ice (300 g) and dichloromethane (300 mL) and charged to a separatory funnel. The organic layer was separated, washed twice with water and brine and dried over MgS04. Filtration and concentration in vacuo afforded 27 as a tan solid. Wt.: 27.6 g (82%). LH NMR (300 MHz, CDCL3) 8 8.79 (dd, 1H), 8.38 (dd, 1H), 8.28 (d, 1H), 7.88 (m, 1H), 7.77 (m, 1H), 7.26 (dd, 1H).

References:

WO2004/58736,2004,A1 Location in patent:Page 158-159