2-(4-Morpholino)thiobenzothiazole → 2-(4-Morpholinyldithio)benzothiazole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

There is charged to a glass or glass-lined reactor 25.2 grams (0.1 mole) of 2-(morpholinothio)benzothiazole, 3.2 grams (0.1 mole) of sulfur, and 150 ml. of essentially anhydrous isopropyl alcohol (0.4% by weight water). The catalyst, the sodium salt of mercaptobenzothiazole, is used in amount of 0.01 mole and is formed in situ by adding 0.01 mole of solid sodium hydroxide and then 0.01 mole of 2-mercaptobenzothiazole (MBT) to the reaction mixture. The reaction mixture is then stirred and heated at refluxing temperature (about 82-83°C) for 2 hours although it is found that the reaction is essentially complete in one hour. A clear solution usually forms in from 15 to 75 minutes. The reaction mixture is cooled to 30°C. during which cooling a precipitate usually begins to form in the range of 67-74°C. Stirring and cooling is continued to 0°C. and the mixture is held at 0-10°C. for about 30 minutes after which it is filtered and the solids air dried at 25-30°C. There is obtained a yield of 94.4-95% of 2-(morpholinodithio)benzothiazole, m.p. 132°-136°C.

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