Patent GB-1257259-A (GB)
IPC: C07D239/60
Filed: 1969-05-13
Abstract: 1,257,259. Uracils. E.I. DU PONT DE NEMOURS & CO. 13 May, 1969 [13 May, 1968], No. 24452/69. Heading C2C. [Also in Division A5] 1-Substituted uracils of the formula R 1  represents an alkyl radical containing 1 to 10 carbon atoms, a substituted alkyl radical containing 1 to 10 carbon atoms, wherein the or each substituent is a bromine, chlorine, hydroxy, alkoxy, alkoxycarbonyl or cyano radical; a substituted or unsubstituted carbocyclic or heterocyclic aromatic radical containing 5 to 16 carbon atoms; an aralkyl radical containing 5 to 13 carbon atoms; a substituted aralkyl radical containing 5 to 13 carbon atoms, wherein the or each substituent is a chlorine, nitro, alkyl or alkoxy radical; an alkenyl radical containing 3 to 8 carbon atoms; an alkynyl radical containing 3 to 8 carbon atoms; a cycloalkyl radical containing 3 to 12 carbon atoms; a substituted cycloalkyl radical containing 3 to 12 carbon atoms, wherein the or each substituent is a bromine, chlorine, methoxy, or alkyl radical; a cycloalkenyl radical containing 4 to 12 carbon atoms; a substituted cycloalkenyl radical containing 4 to 12 carbon atoms, wherein the or each substituent is a bromine, chlorine, methoxy, or alkyl radical; a cycloalkyl alkyl radical containing 4 to 13 carbon atoms; a substituted cycloalkyl alkyl radical containing 4 to 14 carbon atoms; wherein the or each substituent is. a. bromine, chlorine, methoxy, or C 1-4  alkyl radical; a cycloalkenyl, alkyl radical containing 5 to 13 carbon atoms; a substituted cycloalkenyl alkyl radical containing 5 to 14 carbon atoms, wherein the or each substituent is a bromine, chlorine, methoxy or C 1-4  alkyl radical; R 2  represents a hydrogen or a halogen atom or a methyl, ethyl, methoxy, ethoxy,. nitro, alkoxymethyl of 2 to 4 carbon atoms, hydroxyalkyl of 1 to 4 carbon atoms, mercapto -methyl, methylthio, ethylthio, methylmercaptomethyl, bromomethyl, chloromethyl or fluoromethyl radical; R 3  represents a hydrogen or an alkyl radical containing 1 to 3 carbon atoms.; or R 2  and R 3  together represent a divalent radical of the formula (CH 2 )q, wherein q is. 3, 4 or 5; R 4  represents an alkyl. radical containing: 1 to 10 carbon atoms; a. substituted alkyl radical containing 1 to 10 carbon atoms, wherein the or each substituent is a chlorine, bromine, fluorine or alkoxy radical of 1 to 4 carbon atoms; a phenyl radical; a chlorophenyl radical; a benzyl radical; an aryl radical containing 4 to 10 carbon atoms; an alkenyl radical containing 3 or 4 carbon atoms; or a cycloalkyl radical containing 4 to 8 carbon atoms; and X represents an oxygen or sulphur atom.; or the reaction product of a said uracil with a Lewis acid or base are prepared either by (1) reacting with sodium methoxide in the presence of an organic solvent a uracil of formula and (2) reacting the product of step (1) with an excess of R 4 X-CO-Cl or replacing sodium methoxide in the first process by sodium hydride. Amongst numerous. examples the compounds 1 methoxycarbonyl - 3 -sec -butyl-5- bromo - 6 - methyluracil, 1 - (2 - fluoroethoxycarbonyl) - 3 - propargyl - 5 - fluoro - 6 - methyluracil and 1-phenoxycarbonyl-3-cyclopropyl- 5,6-dimethyluracil are prepared. The 1 -substituted uracils of the invention have herbicidal activity and numerous examples of herbicidal compositions are given in the Specification.