申请人:Bayer Aktiengesellschaft
公开号:US05686392A1
公开(公告)日:1997-11-11
The herbicidally active substituted N-carbamoyl-tetrazolinones of the formula (I) ##STR1## in which R.sup.1 represents, inter alia, an (optionally substituted) phenyl radical, R.sup.2 represents, inter alia, an alkyl radical, and R.sup.3 represents, inter alia, a cycloalkyl radical, are obtained in very good yields and at high purity--i.e. free from the isomeric O-carbamoyloxytetrazoles (Ia)--by reacting tetrazolinones of the formula (II) with carbamoyl halides of the formula (III) (X=halogen) ##STR2## in the presence of an acid acceptor and in the presence of a diluent, at temperatures of between 0.degree. C. and 200.degree. C., and either isomerizing the O-carbamoylation product of the formula (Ia), which is formed under these circumstances as a byproduct, into the desired product of the formula (I) by heating, or else converting it by hydrolysis or alcoholysis into water-soluble, and thus readily separable, components (variable (a)). Three variants (b), (c) and (d) which are closely related to this process (a) are also described: Process variant (b) proceeds in analogy with (a) but via the (novel, isolated) metal salts (IIa) of the tetrazolinones (II). In variant (c), the isomer (Ia) is isomerized thermally, either in pure isolated form or mixed with (I), while, in variant (d), the (Ia) isomer is removed from (I)/(Ia) mixtures by means of hydrolysis or alcoholysis. The novel intermediates (Ia) and (IIa) also belong, as such, to the subject-matter of the invention.
公式(I)中具有除其他外,R1代表(可取代的)苯基,R2代表(可取代的)烷基,R3代表(可取代的)环烷基的除草活性取代的N-氨基甲酰基四唑酮可在很好的收率和高纯度下获得,即不含异构体O-氨基甲酰氧基四唑酮(Ia),方法为在酸性受体和稀释剂存在下,以0℃至200℃的温度下,将公式(II)的四唑酮与公式(III)的氨基甲酰卤化物(X=卤素)反应,并将在这些情况下形成的公式(Ia)的O-氨基甲酰化产物通过加热异构化为所需的公式(I)的产物,或通过水解或醇解将其转化为水溶性,因此易于分离的组分(变量(a))。还描述了与此过程(a)密切相关的三种变体(b),(c)和(d):过程变体(b)类似于(a),但通过四唑酮(II)的(新颖的,分离的)金属盐(IIa)进行。在变体(c)中,异构体(Ia)在纯隔离形式或与(I)混合物中通过热异构化,而在变体(d)中,通过水解或醇解从(I)/(Ia)混合物中去除(Ia)异构体。新颖的中间体(Ia)和(IIa)也属于本发明的内容。