Potassium Carbonate → 3-Triphenylmethylthio-2-(t-butoxycarbonylaminoethylthiomethyl)pyridine

Participants

Reaction Conditions

Reaction Steps

Into a 3 L round bottom flask equipped with a mechanical stirrer, thermometer and nitrogen purge was charged 3-triphenylmethylthio-2-hydroxymethylpyridine (40.0 g, 0.104 mol, 1 eq.) followed by DMF (1.2 L). The solution was cooled to 0° C. and a pre-formed solution of thionyl chloride (12.4 g, 0.104 mol, 1.0 eq.) in DMF (200 mL) was charged dropwise over approximately 5 minutes. To this orange coloured solution was charged BOC-cysteamine (18.4 g, 0.104 mol, 1 eq.) followed by finely powdered potassium carbonate (43.1 g, 0.104 mol, 1 eq) and the resulting suspension was vigorously stirred for two hours until TLC analysis showed reaction completion (1:1 EtOAc/hexanes). The solution was poured into a 3 L of a 4:1 mixture of ice water/4:1 ethyl acetate-hexane. The aqueous was separated and extracted with an additional 200 mL of 4:1 ethyl acetate-hexane. The organics were combined and washed with water (2×200 mL) then brine (2×200 mL). The organic layer was dried with sodium sulfate, filtered and the solvent was removed in vacuo to give 54 grams of a brown oil. This oil was purified by column chromatography on silica gel to give 41 grams of the title compound as a light yellow oil. 1H NMR (CDCl3) δ 1.41 (s, 9H); 2.77 (t, 2H); 3.42 (t, 3H); 4.11 (s, 2H); 7.05-7.45 (m, 16H); 8.22 (d, 1H); 8.65 (d, 1H).

Provenance & Evidence