苯噻菌胺的合成研究

Study of Synthetic Process of Novel of Fungicides Benthiavalicarb

对氟苯胺在盐酸的作用下与硫氰酸铵反应得到对氟苯基硫脲,然后在溴的作用下环化得到2-氨基-6-氟苯并噻唑;2-氨基-6-氟苯并噻唑水解并与氯化锌反应得2-氨基-5-氟苯硫酚锌盐;2-氨基-5-氟苯硫酚锌盐与D-丙氨酸-N-羰酐反应得到(R)-1-(6-氟-2-苯噻唑)乙胺。最后,(R)-1-(6-氟-2-苯噻唑)乙胺与L-缬氨酸和氯甲酸异丙酯反应得到目的产物苯噻菌胺,总收率51.2%(以对氟苯胺计)。

P-fluoroaniline reacted with ammonium thiocyanate in the present of hydrochloric acid to give 4-fluoro-phenylthioureas, then 4-fluoro-phenylthioureas reacted with bromine in the solution of chloroform to give the 2-amino-6-fluorol-benzothiazoles. In the present of NaOH, 2-amino-6-fluorol-benzothiazoles hydrolyzed and reacted with ZnCl2 to give the bis（5-fluoro-2-aminothiophenol） zinc salt. （R）-1-（6-fluoro-2-benzothiazoly）ethylamine was prepared by the reaction of bis（5-fluoro-2-aminothiophenol） zinc salt with D-alanine-N-carboxy anhydride. Under the catalytic of NaOH, （R）-1-（6-fluoro-2-benzothiazoly） ethylamine reacted with L-valine and isopropyl chlorocarbonate to give the target production of benthiavalicarb. The total yield is 51.2%（calculation on p-fluoroaniline）.