Planar and Curved π-Extended Porphyrins by On-Surface Cyclodehydrogenation

. 2024 Dec 18 ; 146 (50) : 34600-34608. [epub] 20241204

Status PubMed-not-MEDLINE Jazyk angličtina Země Spojené státy americké Médium print-electronic

Typ dokumentu časopisecké články

Perzistentní odkaz   https://www.medvik.cz/link/pmid39629975

Recent advancements in on-surface synthesis have enabled the reliable and predictable preparation of atomically precise low-dimensional materials with remarkable properties, which are often unattainable through traditional wet chemistry. Among these materials, porphyrins stand out as a particularly intriguing class of molecules, extensively studied both in solution and on surfaces. Their appeal lies in the ability to fine-tune their unique chemical and physical properties through central metal exchange or peripheral functionalization. However, the synthesis of π-extended porphyrins featuring unsubstituted anthracenyl groups has remained elusive. Herein, we report an in vacuo temperature-controlled cyclodehydrogenation of bis- and tetraanthracenyl Zn(II) porphyrins on a gold(111) surface. By gradually increasing the temperature, sequential dehydrogenation leads to the formation of fused anthracenyl porphyrin products. Notably, at high molecular coverage, the formation of bowl-shaped porphyrins occurs, along with transmetalation of Zn with Au. These findings open the door to a variety of π-extended anthracenyl-containing porphyrin products via cyclodehydrogenation and transmetalation, offering significant potential in the fields of molecular (photo/electro)catalysis, (opto)electronics, and spintronics.

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