Process for the preparation of 3-substituted thiophenes
Реферат: An improved process for the preparation of 3-substituted thiophenes. The thiophenes are useful for the preparation of penicillins and cephalosporins. The process is for the preparation of a thiophene of formula (1): where R' represents a carboxylic acid group, or an ester or amide thereof or a nitrile group; R' represents a group suitable for use as an a-substituent in the side- chain of a penicillin or cephalosporin; which comprises treating under basic conditions a compound of formula [II]: wherein X represents halogen or optionally functionalised hydroxyl, Y represents halogen, hydroxyl, or alkoxy; with a source of nucleophilic sulphur ionically bound to a polymeric support.
Process for the preparation of thiophenes
Номер патента: US4252976A. Автор: Angela W. Guest,Andrew W. Taylor,Robert Ramage. Владелец: Beecham Group PLC. Дата публикации: 1981-02-24.