Bicyclo[1.1.1]pentane Embedded in Porphyrinoids**

Abstract

AbstractWe report a two‐step approach to obtain synthetically versatile bicyclo[1.1.1]pentane (BCP) derivatives using Grignard reagents. This method allows the incorporation of BCP units in tetrapyrrolic macrocycles and the synthesis of a new class of calix[4]pyrrole analogues by replacing two bridging methylene groups with two BCP units. In addition, a doubly N‐confused system was also formed in the presence of electron‐withdrawing substituents at the BCP bridgeheads. The pyrrole rings in BCP containing macrocycles exist in 1,3‐alternate or αβαβ conformations, as observed from single‐crystal X‐ray diffraction analyses and 2D NMR spectroscopy.