Process for the production of phenthiazines
Номер патента: GB757794A
Опубликовано: 26-09-1956
Автор(ы):
Принадлежит: Rhone Poulenc SA, Societe des Usines Chimiques Rhone Poulenc SA
Опубликовано: 26-09-1956
Автор(ы):
Принадлежит: Rhone Poulenc SA, Societe des Usines Chimiques Rhone Poulenc SA
Реферат: 757,794. Phenthiazine derivatives. SOC. DES USINES CHIMIQUES RHONE-POULENC. Jan. 27, 1954 [April 8, 1953], No. 9592/53. Addition to 757,795. Class 2 (3). Phenthiazines are prepared by bringing about cyclization in an anhydrous solvent, at elevated temperature and in the presence of an acid binding agent of a diphenylsulphide orthosubstituted in one ring by an amino group and in the other ring by a halogen atom (preferably bromine), all of the remaining positions being unsubstituted or at least one of the remaining positions (preferably ortho or para) being substituted by a halogen atom (preferably chlorine or bromine) or a lower alkyl (preferably methyl or ethyl), lower alkoxy (preferably methoxy or ethoxy) or a phenoxy group; the term " lower " implying the presence of up to 6 carbon atoms. The reaction is preferably conducted at or near the boiling point of the reaction mixture at the pressure employed, e.g. by refluxing. The solvent is preferably an N-substituted amide of a fatty acid containing up to 3 carbon atoms (e.g. dimethylformamide and N-methylacetamide), and the acid binding agent is preferably potassium or sodium carbonate, preferably in conjunction with a dehydrohalogenation catalyst such as copper powder. The examples describe the preparation of phenthiazine and 2-chloro-, 3-chloro- and 4-chlorophenthiazine. 2 - Bromo- 2<SP>1</SP>- amino-, 2 - - bromo -2<SP>1</SP>- amino- 4<SP>1</SP> - chloro- and 2 - bromo - 2<SP>1</SP> - amino - 5<SP>1</SP> - chloro -diphenylsulphide are prepared by stannous chloride reduction of the corresponding nitro derivatives. 2-Bromo-2<SP>1</SP>-nitro-, 2-bromo-21-nitro-41-chloro- and 2 -bromo - 2<SP>1</SP>-nitro- 5<SP>1</SP>-chloro -diphenylsulphide are prepared by reacting 2-bromothiophenol with 2-chloro-, 2: 5-dichloro- and 2: 4-dichloronitrobenzene respectively. Specifications 716,205, 724,218, 757,797 are referred to.
Improvements in processes for the hydrogenation of products of aldolic condensation
Номер патента: GB908495A. Автор: . Владелец: SNIA Viscosa SpA. Дата публикации: 1962-10-17.