Manufacture of cyclopentanecarboxylic acid derivatives

摘要

The invention comprises 2-nitrocyclopent-1-enecarboxylic acid and salts and esters thereof, processes for the preparation of the acid wherein (a) 1-iodo-2-nitro-cyclopentanecarboxylic acid is interacted with pyridine at about 18-2 DEG C.; (b) 1-hydroxy-2-nitrocyclopentane carboxylic acid is heated with dimethyl sulphoxide or (c) 1-hydroxy-2-nitrocyclopentane carboxylic acid or 1-amino-2-nitro-cyclopentane-carboxylic acid is hydrolysed by heating in an aqueous medium in the presence of an inert gas and a process for the manufacture of 1-amino-2-nitrocyclopentane carboxylic acid in which a compound of the formula or wherein X stands for a halogen atom or a hydroxy, methanesulphonyloxy, p-toluenesulphonyloxy or acetoxy, nitrite or nitrate radical with ammonia. 1 - iodo - 2 - nitrocyclopentane carboxylic acid is prepared by reacting cyclopentane carboxylic acid and iodine in ether with dinitrogen tetroxide. Examples are furnished.