Synthesis of 2-Pyridyl Tribromomethyl Sulfone

Abstract

Polyethylene glycol-400 was used as phase transfer catalyst in reaction of dichloropyridine and sodium thiomethoxide to form 2-methylthiopyridine with a yield of 97.8%. Then 2-methylthiopyridine and sodium hypochlorite were added respectively to oxidize and bromize it to synthesis 2-Pyridyl tribromomethyl sulfone, with the purity of 99.6% and yield of 93.3%. Mass ratio of dichloropyridine versus polyethylene glycol-400 is 1:0.18, and molar ratio of dichloropyridine versus sodium thiomethoxide is 1:1.2. The optimum conditions to prepare sodium hypochlorite are a temperature at-5 to 0 °C, a molar ratio of bromine versus sodium hydroxide being 1:4. Proved optimum conditions to synthesis 2-pyridyl tribromomethyl sulfone are a temperature at (80±1)°C, reaction time for 5 hours and the molar ratio of 2-methylthiopyridine versus bromine being 1:6.58. Probable mechanism of synthetizing 2-methylthiopyridine was speculated, properties with structure of resultant substances were characterized by melting point apparatus, IR spectra and magnetic resonance spectrum.</jats:p