Heptathiazocine

Heptathiazocine (1.4 g, 5.85 mmole) is dissolved in anhydrous diethyl ether (150 mL) in a 250-mL, three-necked flask. The solution is cooled to -78° (acetone-Dry Ice) under nitrogen and tetrabutylammonium hydroxide 7.5 mL of 25% solution in methanol, Eastman, 7.25 mmoles) in diethyl ether (12.5 mL) is added slowly. A yellow precipitate (sometimes with a greenish tinge) is formed immediately. The solution is kept at -78° and filtered through a coarse glass frit in a low-temperature filter funnel (Kontes, airless-ware). The greenish-yellow solid on the frit is transferred quickly to a dry box, and in the course of about 1 day it becomes a deep-purple solid. This solid contains elemental sulfur (x-ray... 

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