## Abstract 2‐Alkoxy‐5‐chloromethy1‐1,3,4‐thiadiazoles are prepared by ring closure of 3‐chloroacetyl‐thiocarbazic acid O‐alkyl esters with concentrated sulfuric acid, 2‐alkylthio‐5‐chloro‐methy1‐1,3,4‐thiadiazoles directly from dithiocarbazic acid alkylesters with chloroacetylchloride in benzene i
Arbeiten über Phosphorsäure- und Thiophosphorsäureester mit einem heterocyclischen Substituenten. 4. Mitteilung. 3-Isopropyliden-dithiocarbazinsäure-alkylester und deren Ringschluss zu 5-Alkylthio-1,3,4-thiadiazol-2(3H)-onen
✍ Scribed by K. Rüfenacht
- Publisher
- John Wiley and Sons
- Year
- 1972
- Tongue
- German
- Weight
- 210 KB
- Volume
- 55
- Category
- Article
- ISSN
- 0018-019X
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Impurities in crude oily dithiocarbazic acid (2′‐methoxy)‐ethyl ester causing troubles in the ring closure to 5‐(2′‐methoxy‐ethylthio)‐1,3,4‐thiadiazol‐2(3H)‐one and in succeeding reactions are eliminated by using the crystalline 3‐isopropylidene‐dithiocarbazic acid (2′‐methoxy)‐ethyl ester, which can be obtained directly by alkylation of potassium dithiocarbazate with 2‐methoxy‐ethyl bromide in presence of acetone. By the action of phosgene followed by that of water, the isopropylidene compound yields the oily 5‐(2′‐methoxy‐ethylthio)‐1,3,4‐thiadiazol‐2(3H)‐one by splitting off the isopropylidene group and by ring closure in one single step.
📜 SIMILAR VOLUMES
## Abstract Some 1,3,4‐oxadiazol‐2(2__H__)‐ones with aliphatic substituents in 5‐position are prepared in good yields and converted __via__ the 3‐hydroxymethyl derivatives to the corresponding 3‐chloromethyl derivatives which are suitable starting materials for the preparation of insecticidal O,O‐d