Ethyldithio hexadecanoic acid

To a solution of ethyl 2-pyridyl disulfide (55 mg, 0.32 mmol) and DMAP (33mg, 0.27mmol) in dichloromethane (2ml) was added 2-mercaptohexadecanoic acid (77 mg, 0.27 mmol). The progress of the reaction was monitored by TLC (silica, CHCl,/MeOH 9 1). Upon completion (1 h) the product mixture was passed through a column (0.5 X 5 cm) of AG MP-50 (0.5 g, 3.5 meq (ml dry resin)Bio-Rad Laboratories). Elution with 3 ml of dichloromethane, followed by concentration of the filtrate under reduced pressure, afforded 2-(ethyldithio)hexadecanoic acid (91 mg, 98%) as a colourless oil. 

The following routes to unsymmetrical disulfides and symmetrical trisulfides use silyl sulfides and thiosulfinates [41.42]. Thiosulfonates react similarly. 

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