Process for the preparation of furopyrroles

Abstract

The present invention relates to a process for the preparation of furopyrroles of general formula (I), comprising (a) heating a compound of the formula (II) under microwave irradiation optionally in the presence of an inert solvent, wherein A1 and A2 are C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C5-C8cycloalkyl, C5-C8cycloalkenyl, aryl or heteroaryl, A3 is hydrogen, C1-C18alkyl, cyanomethyl, Ar3, —CR30R31—(CH2)m—Ar3 or Y—R32, wherein R30 and R31 independently of each other stand for hydrogen or C1-C4alkyl, or phenyl which can be substitute up to three times with C1-C4alkyl, Ar3 stands for aryl, C5-C8 cloalkyl, C5-C8cycloalkenyl or heteroaryl, which can be substituted one to three times with C1-C8alkyl, C1-C8alkoxy, halogen or phenyl, which can be substituted with C1-C8alkyl 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 R32 is C1-C18alkyl, Ar3, or aralkyl. The furopyrroles of the general formula (I) can be can be obtained in high yield and high purity by the process of the present invention.

Dependencies are inferred from the claim text.