Process for the preparation of trisubstituted ureas
Реферат: 1504534 Preparation of trisubstituted ureas QUIMCO GmbH 13 Aug 1976 [13 June 1975] 21686/75 Heading C2C The invention relates to a process for preparing a trisubstituted urea of the general formula R(NHCONR<SP>1</SP>R<SP>11</SP>) n in which R is an aromatic, aliphatic or heterocyclic radical, which may be substituted by one or more atoms or groups that are inert under the conditions of the reaction, R<SP>1</SP> and R<SP>11</SP> are monovalent aliphatic radicals and n is an integer, in which an amine of the general formula R(NH 2 ) n is reacted in a solvent with a stoichiometric excess of a secondary ammonium N,N-disubstituted thiolcarbamate of the general formula and in which a part or all of the starting material which remain after the reaction and any intermediate compound which are produced during the reaction, and which distil with the solvent or at a temperature below the boiling point of the solvent are recycled into the manufacture of additional quantities of the said secondary ammonium N,N-disubstituted thiolcarbamate. Example I describes the preparation of 1 - (3,4 - dichlorophenyl) - 3,3- dimethylurea wherein. the volatiles obtained after the reaction are collected and reacted with (CH 3 ) 2 NH, sulphur and carbon monooxide in an autocalve to produce dimethylammonium N,N - dimethylthiol carbamate. In Example 5, dimethylammonium - N,N - dimethyl - thiolcarbamate is reacted with 3 - aminopyridine to form 1,1-dimethyl-3-(3-pyridyl)urea.
Process for the preparation of tivozanib or a salt thereof
Номер патента: WO2024157170A1. Автор: Pratik Patel,Venkata Raghavendra Acharyulu Palle,Premkumar Ramraj YADAV,Raj Mahendra SHANMUGHASAMY. Владелец: Glenmark Life Sciences Limited. Дата публикации: 2024-08-02.