Process for the preparation of 4-methyl-5-(2-chloroethyl)-thiazole and analogues thereof
US5534644A · kind A · utility
Assignee
Inventors
- Endre Palosi
- Dezso Korbonits
- Erzsebet Molnar nee Bako
- Ida Szvoboda nee Kanzel
- Gergely Heja
- Pal Kiss
- Csaba Gonczi
- Ferenc Sperber
- Csaba Huszar
- Gyorgy Mihalovics
- Attila Nemeth
- Mihaly Su
- Karol Gyure
- Istvan Bone
- Ferenc Morasz
- Laszlo Ledniczky
- Erzsebet Szabo nee Kardos
- Peter Gy ri
- Erzsebet Szalay
- Karoly Ban
- Iidiko Buttkai
- Arpad K vari
- Sandor Garaczy
Key dates
| Filing date | Jun 5, 1995 |
| Grant date | Jul 9, 1996 |
| Priority date | — |
| Expiry date | Jun 5, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07D277/34
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a process for the preparation of compounds of general formula (I), wherein R stands for a straight chained C.sub.1-5 alkyl group substituted by a chlorine atom in the 2-position, and acid addition salts thereof, characterized by reacting a 3,5-dichloro-2-alkanone of general formula (V), wherein R is a defined above, with an inorganic thiocyamate, and a) converting the 3-thiocyanato-5-chloro-2-alkanone of general formula (IV), thus obtained, wherein R is as defined above, into 2-chloro-4-methyl-5-(2-chloroalkyl)-thiazole of general formula (II), wherein R is as defined above, by gaseous hydrochloric acid in an organic solvent, hydrogenating the said compound in the presence of a metal catalyst in an organic solvent, or b) reacting said compound of general formula (IV) with an aqueous mineral acid and treating the 2-hydroxy-4-methyl-5-(2-chloroalkyl)-thiazole of general formula (III), thus obtained with a halogenating agent, and hydrogenating the 2-chloro-4-methyl-5-(2-chloroalkyl)-thiazole of general formula (II) thus obtained, wherein R is as defined above, in an organic solvent in presence of a metal catalyst, and optionally converting the 4-methyl…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.