A 1-lower alkoxy-1-lower alkyl-3-[4-(2-lower alkoxy-2,3-dihydro-7-benzopyranyloxy)phenyl]-urea is prepared by a process which comprises alkylating a novel 1-hydroxy-3-[4-(2-lower alkoxy-2,3-dihydro-7-benzopyranyloxy)phenyl]urea with a corresponding alkylating agent selected from the group consisting of a sulfuric acid ester and an alkyl halide in the presence of a basic compound. The 1-lower alkoxy-1-lower alkyl-3-[4-(2-lower alkoxy-2,3-dihydro-7-benzopyranyloxy)phenyl]urea has a herbicidal activity. New intermediates and processes for production thereof are also disclosed.
                            一种 1-低级烷氧基-1-低级烷基-3-[4-(2-低级烷氧基-2,3-二氢-7-苯并
吡喃氧基)苯基]
脲的制备方法包括在碱性化合物存在下,将新型 1-羟基-3-[4-(2-低级烷氧基-2,3-二氢-7-苯并
吡喃氧基)苯基]
脲与选自
硫酸酯和烷基卤化物组成的组中的相应烷基化剂烷基化。1-低级烷氧基-1-低级烷基-3-[4-(2-低级烷氧基-2,3-二氢-7-苯并
吡喃氧基)苯基]
脲具有除草活性。此外,还公开了新的中间体及其生产工艺。