149217-16-3Relevant academic research and scientific papers
Thermal rearrangement of N-alkyl-, and N-aryl-(2,2-dihalo-1-phenylcyclopropyl)methyleneamines to 1-alkyl-, and 1-aryl-2 (or 3)-halo-4-phenylpyrroles
Kagabu,Tsuji,Kawai,Ozeki
, p. 341 - 349 (2007/10/02)
The thermolysis of N-t-alkyl-, and N-aryl-(2,2-dichlorocyclopropyl)methyleneamines yielded directly 1-t-alkyl, and 1-aryl-3-chloropyrroles as the major products along with a slight amount of the 2-chloro isomers. The transformation to the 3-chloropyrroles was enhanced in polar solvents. But basic additives directed the thermal rearrangement into the 1,2-bond cleavage of the cyclopropane ring, leading to the 2-chloropyrroles. On the other hand, (difluorocyclopropyl)methyleneamines were pyrolyzed exclusively to 3-fluoropyrroles under 1,3-bond cleavage. The ionic mechanism involving a heterolytic dissociation of chlorine atom under 1,3-bond scission of the cyclopropane ring is proposed for the rearrangement to 3-chloropyrroles, while a homolytic cleavage pathway is proposed for 3-fluoropyrroles. The present thermolysis supplies a unique preparative tool for 2-, and 3-halo-4-phenylpyrrole derivatives.
2- and 3-chloropyrroles and process for preparing the same
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, (2008/06/13)
Novel 2- or 3-chloropyrroles represented by the general formula: STR1 wherein R1 represents hydrogen atom, chlorine atom, alkyl group, or aryl group which may optionally be substituted, with the proviso that any one of the two groups represente
