306763-51-9Relevant academic research and scientific papers
Organometallic complexes for nonlinear optics: Part 19. Syntheses and molecular quadratic hyperpolarizabilities of indoanilino-alkynyl-ruthenium complexes
McDonagh, Andrew M.,Cifuentes, Marie P.,Lucas, Nigel T.,Humphrey, Mark G.,Houbrechts, Stephan,Persoons, André
, p. 193 - 201 (2000)
The terminal alkyne 4-HCCC6H4N=CCH=CtBuC(O)CtBu=CH (1) and ruthenium complex derivatives trans-[Ru(CC-4-C6H4N=CCH=CtBuC(O)C tBu=CH}Cl(dppm)2] (2) and [Ru{CC-4-C6H4N=CCH=CtBuC(O)C tBu=CH}(PPh3)2(η-C5H 5)] (3) have been synthesized. An X-ray structural study of 3 reveals the expected equivalent C-C bond lengths of the phenyl and alternating C-C and C=C bond lengths of the quinonal ring in the indoanilino-alkynyl ligand; there is a dihedral angle of 47.59° between the phenyl and quinonal rings, probably a result of ortho-hydrogen repulsion. Metal-centred oxidation potentials of 2 and 3 are similar to those of 'extended chain' 4-nitroaryl-alkynyl complex analogues. Irreversible quinonal ring-centred reductions occur at significantly more negative potentials than the quasi-reversible reductions in their nitro-containing analogues. Quadratic optical nonlinearities by hyper-Rayleigh scattering at 1064 nm for 2 (417×10-30 esu) and 3 (658×10-30 esu) are both large, but resonance enhanced. Two-level-corrected nonlinearities for these complexes (124×10-30, 159×10-30 esu, respectively) are also large, despite the presence of electron-donating tert-butyl groups reducing the efficiency of the (formally) electron-accepting quinonal ring in these donor-bridge-acceptor complexes.
Active ester functionalized azobenzenes as versatile building blocks
Schultzke, Sven,Staubitz, Anne,Walther, Melanie
, (2021/07/12)
Azobenzenes are important molecular switches that can still be difficult to functionalize selectively. A high yielding Pd-catalyzed cross-coupling method under mild conditions for the introduction of NHS esters to azobenzenes and diazocines has been established. Yields were consistently high with very few exceptions. The NHS functionalized azobenzenes react with primary amines quantitatively. These amines are ubiquitous in biological systems and in material science.
