PROCESS FOR THE PREPARATION OF FUROPYRROLES

摘要

The present invention relates to a process for the preparation of furopyrroles of the general formula (I), comprising (a) heating a compound of the formula (II) under microwave irradiation optionally in the presence of an inert solvent, wherein A<1 >and A<2> are Cl-C18alkyl, C2-Cl8alkenyl, C2-Cl8alkynyl, C5-C8cycloalkyl, C5- C8cycloalkenyl, aryl or heteroaryl, A<3> is hydrogen, C1-C18alkyl, cyanomethyl, Ar<3 >,-CR<30>R<31>-(CH2< >)m< >-Ar<3> or Y- R<32 >, wherein R<30 >and R<31> independently of each other stand for hydrogen or C1-C4alkyl, or phenyl which can be substituted up to three times with C1-C4alkyl, Ar<3 >stands for aryl, C5-C8 cloalkyl, C5-C8 cycloalkenyl or heteroaryl, which can be substituted one to three times with C1-C8alkyl, C1-C8alkoxy, halogen or phenyl, which can be substituted with C1-C8alkyI or C1-C8alkoxy one to three times, and m stands for 0, 1, 2, 3 or 4, R is C1-C18alkyl, in particular C1-C4alkyl, aryl, in particular phenyl, or aralkyl, in particular benzyl, which can be substituted one to three times with C1-C8alkyl, C1-C8alkoxy, or halogen, Y is -C(O)-, -C(O)O-, -C(O)NH-, -SO2NH- or -SO2- and R<32> is C1-Cl8alkyl, Ar<3>, or aralkyl. The furopyrroles of the general formula (I) can be obtained in high yield and high purity by the process of the present invention.