Chlorosulfonic acid → 3-Trifluoroacetyl-1,2,4,5-tetrahydro-3-benzazepine-7-sulfonyl chloride

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Reaction Steps

Chlorosulphonic acid (10.4 ml, 0.156 mol) was added dropwise to a stirred, cold solution of the product from (b) above (5.85 g, 11.7 mmol) in dichloromethane, whilst ensuring that the temperature of the reaction mixture was held between -12° and -8° C. After 2 days at room temperature, the reaction solution was poured onto ice and the aqueous phase separated and extracted with dichloromethane. The combined organic extracts were dried (MgSO4) and evaporated under reduced pressure to provide an oil (7.9 g) which was purified by chromatography on silica gel, using a mixture of hexane and ether (1:3) as eluant, to give the title compound as a colourless oil which eventually solidified. Crystallisation of a sample from diisopropyl ether produced a white solid. m.p. 87°-88° C. Found: C,41.75; H,3.18; N,3.92. C12 H11Cl F3NO3S requires C,42.17; H,3.24; N,4.10%.

Provenance & Evidence