申请人:Seitetsu Kagaku Co., Ltd.
公开号:US04792612A1
公开(公告)日:1988-12-20
Novel compounds, 2-(.alpha.-alkoxyimino)ethylthiophenes are susceptible to electrophilic substitution reactions, and the acetylation, nitration, sulfonation and halogenation of the compounds provide 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-nitro-2-(.alpha.-alkoxyimino)ethylthiophenes, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenesulfonic acid and 5-halo-2-(.alpha.-alkoxyimino)ethylthiophenes, respectively. The hydrolysis of 5-acetyl-2-(.alpha.-alkoxyimino)ethylthiophenes readily provides a known compound, 2,5-diacetylthiophene which is an important intermediate for the production of medicines, whereas the haloform reaction provides novel compounds, 5-(.alpha.-alkoxyimino)ethyl-2-thiophenecarboxylic acids, the hydrolysis of which compounds readily provides a known compound, 5-acetyl-2-thiophenecarboxylic acids, an important intermediate for the production of medicines. The hydrolysis of 5-(.alpha.-alkoxyimino)ethyl-2-thiophenesulfonic acids and their salts provide novel 5-acetyl-2-thiophenesulfonic acid and its salts, respectively. Novel compounds, 2-(.alpha.-alkoxyimino)ethylthiophenes are obtained either by 0-alkylation of 2-acetylthiophene oxime or by directly reacting 2-acetylthiophene with an 0-alkylhydroxylamine.
新化合物2-(α-烷氧基亚胺)乙基噻吩易受亲电取代反应影响,化合物的乙酰化、硝化、磺化和卤代反应提供5-乙酰基-2-(α-烷氧基亚胺)乙基噻吩、5-硝基-2-(α-烷氧基亚胺)乙基噻吩、5-(α-烷氧基亚胺)乙基-2-噻吩磺酸和5-卤代-2-(α-烷氧基亚胺)乙基噻吩。5-乙酰基-2-(α-烷氧基亚胺)乙基噻吩的水解容易提供已知化合物2,5-二乙酰基噻吩,这是生产药物的重要中间体,而卤仿反应提供新化合物5-(α-烷氧基亚胺)乙基-2-噻吩羧酸,这些化合物的水解容易提供已知化合物5-乙酰基-2-噻吩羧酸,这是生产药物的重要中间体。5-(α-烷氧基亚胺)乙基-2-噻吩磺酸及其盐的水解提供新的5-乙酰基-2-噻吩磺酸及其盐。新化合物2-(α-烷氧基亚胺)乙基噻吩可通过2-乙酰基噻吩肟的0-烷基化或直接将2-乙酰基噻吩与0-烷基羟胺反应而获得。