申请人:Novartis AG
公开号:US05883253A1
公开(公告)日:1999-03-16
The invention relates to a process for the prepn of ortho-sulfocarboxylic acids, which comprises: a) in a first reaction step, diazotizing an aromatic o-aminosulfonic acid in the presence of an acid and nitrite in water, in an organic solvent or in a mixture thereof, to an o-diazonium sulfonate, and, b) in a second reaction step, reacting the o-diazonium sulfonate in the presence of a palladium catalyst in water, in an organic solvent or in a mixture thereof, with carbon monoxide, under overpressure, to an aromatic o-sulfocarboxylic acid. The invention also relates to a process for the preparation of sulfonylureas using o-sulfocarboxylic acids as intermediates. Thus, 4-methoxyaniline-2-sulfonic acid was diazotized and treated with CO to give 97% 4-methoxybenzoic acid 2-sulfonic acid.
本发明涉及一种制备邻磺酰基羧酸的方法,包括:a)在第一反应步骤中,在水、有机溶剂或二者混合物中,在酸和亚硝酸盐的存在下,重氮化芳香族邻氨基磺酸为邻重氮基磺酸盐;b)在第二反应步骤中,在水、有机溶剂或二者混合物中,在钯催化剂的存在下,通过过量压力下与一氧化碳反应,将邻重氮基磺酸盐转化为芳香族邻磺酰基羧酸。本发明还涉及一种以邻磺酰基羧酸为中间体制备磺酰脲类化合物的方法。因此,4-甲氧基苯胺-2-磺酸被重氮化并与CO反应,得到97%的4-甲氧基苯甲酸-2-磺酸。