Synthesis of Doubly β‐to‐β 1,3‐Butadiyne‐Bridged Diporphyrins: Enforced Planar Structures and Large Two‐Photon Absorption Cross Sections

Plane and simple! Doubly β-to-β 1,3-butadiyne-bridged diporphyrins have been synthesized efficiently through metal-catalyzed reactions. The double bridges enforce the two porphyrins in a perfectly planar conformation (see picture), which leads to almost a 100 % increase in the two-photon absorption cross section. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2007/z700550_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.