Pyrithione → Heptadecane

Beteiligte Stoffe

Reaktionsschritte

286 mg (1 mmol) of stearic acid (7) are mixed with 151 mg (1.2 mmol) of N-hydroxypyridine-2-thione, 183 mg (1.5 mmol) of p-dimethylaminopyridine (DMAP) and 310 mg (1.5 mmol) of dichlorohexylcarbodiimide (DCC). The mixture in 20 ml of benzene is stirred under an atmosphere of nitrogen and the solution obtained is brought to reflux so as to distil 10 ml of benzene. After 45 minutes under reflux, 10.8 ml (3 mmol) of tri-n-butylstannane and 10 mg of azobis(isobutyronitrile) (AIBN) in 10 ml of benzene are added dropwise during 15 minutes. Heating under reflux is continued for 6 hours, 10 ml of carbon tetra-chloride are then added, and refluxing is continued for one hour before evaporating the mixture to dryness. The residue is treated with iodine (20% in 10 ml CH2Cl2) and potassium fluoride (10% in 10 ml H2O), and the two phases are then vigorously stirred for 10 minutes. The polymeric tin residues are filtered under vacuum on Celite and washed with 5 ml of dichloromethane. The organic phase is removed and the aqueous layer is extracted twice with dichloromethane (2×10 ml). The combined organic phases are washed with sodium thiosulfate (10%, 10 ml) and 10 ml of water, dried over sodium sulfate, filtered and evaporated to dryness. The crude product purified by filtration on silica gel (100% pentane) gives 228 mg of n-heptadecane (8).

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