2-Thiocresol → Dichloro-(2-methylphenylthio)-1,2,4-triazine

Participants

Reaction Conditions

Reaction Steps

3,5,6-Trichloro-1,2,4-triazine (0.50 g) was dissolved in dry tetrahydrofuran (8 ml) and dry potassium carbonate (0.37 g) and 4Å molecular sieves (180 mg, activated overnight at 180° C.) were added. The stirred mixture was cooled to 0° C. and a solution of o-thiocresol (0.36 g) in dry tetrahydrofuran (4 ml) was added dropwise. After 45 minutes at 0-5° C. and standing overnight at 10° C., the mixture was diluted with dichloromethane (20 ml) and filtered through Hyflo Supercel filter aid covered with a layer of Merck silica 60. The filtrate was concentrated under reduced pressure to afford a single dichloro-(2-methylphenylthio)-1,2,4-triazine (unidentified regioisomer) as a yellow oil (0.86 g) which crystallised on standing. Recrystallisation from ether-n-hexane yielded a pale yellow powder (0.57 g, 77%); m.p. 93-95° C.; IR max (nujol mull): 1460, 1250 cm-1 ; 1H NMR: δ2.38 (3H,s), 7.24-7.37(1H,m), 7.37-7.54(3H,m) ppm.

Provenance & Evidence