Preparation of 5-unsubstituted 4-formylpyrrole-2-carboxylates and conversion to cycloalkano-oligopyrroles †
作者:Yumiko Fumoto、Hidemitsu Uno、Satoshi Ito、Yuka Tsugumi、Maki Sasaki、Yukiko Kitawaki、Noboru Ono
DOI:10.1039/b003360j
日期:——
Ethyl 4-formylpyrrole-2-carboxylates were prepared from nitroacetaldehyde dimethyl acetal in 9–50% yields using the Barton–Zard reaction. These formylpyrroles were successfully transformed to cycloalkano-oligopyrroles. The conformation of cyclononatripyrroles in CDCl3 was found to be a crown form based on the NMR analysis, while cyclododecatetrapyrroles were in two interconverting boat and chair conformations.