Synthesis and Characterization of Aminoquinonato Bridged Re(I)‐Based Amide Functionalized Dinuclear Metallastirrups and Tetranuclear Lemniscate Metallacycles

Abstract

AbstractHerein, we describe a multicomponent self‐assembly approach that has the prospect of furnishing functionalized di‐ and tetranuclear metallacyclic architectures with a very less level of constitutional control using semi‐rigid ligands. The methodology relies on the coordination preference of the metal and the directionality of the ligands. Self‐assembly of Re2(CO)10, aminoquinone ligands (H2L=2,5‐bis(n‐butylamino)‐1,4‐benzoquinone (bbbq), 2,5‐bis(n‐octylamino)‐1,4‐benzoquinone (bobq) and 2,5‐bis(phenethylamino)‐1,4‐benzoquinone (bpbq)) and ditopic pyridyl ligands (N‐L′‐N=bis(4‐pyridinecarboxamide)‐1,2‐ethane (bpce), N,N′‐(1,2‐phenylene)diisonicotinamide (pdia) and N,N′‐bis(4‐pyridylformamide)‐1,4‐benzene (bpfb)) in equimolar ratio afforded amide functionalized metallacyclophanes of 1–9 (Scheme ). Compounds 1–9 have been characterized by elemental analysis, IR, NMR, UV/Vis absorption and ESI‐mass spectroscopic techniques. Molecular structures of 1, 3 and 7 were ascertained by single‐crystal X‐ray diffraction methods.