Linda Maguire, Corey M. Seward, Sladjana Baljak
Aug 1, 2009
Citations
0
Influential Citations
12
Citations
Journal
European Journal of Inorganic Chemistry
Abstract
Reaction of 4,5-diazafluoren-9-one (dafone, 6) and zinc dichloride yields [(dafone)ZnCl2(H2O)] (11) in which the ZnCl2 moiety is coordinated to a single nitrogen atom and also to a molecule of water. Hydrogen bonding, not only to the uncomplexed nitrogen atom of dafone but also to the ketonic oxygen atom of a neighbouring molecule, leads to a zigzag chain structure. In contrast, reaction with anhydrous zinc iodide forms cis-(dafone)2ZnI2 (12) in which the metal–nitrogen distances – 2.170(5) and 2.456(5) A – are significantly different. Dafone, in the presence of dimethyl sulfoxide, reacts with K2PtCl4 to produce square-planar (dafone)PtCl2(dmso) (13), whereas with K2PtBr6 the octahedral complex (dafone)PtBr4 (14) is formed in which the ligand chelates in a symmetrical fashion. Treatment of dafone with phenylethynyllithium furnishes 9-phenylethynyl-4,5-diazafluoren-9-ol (7), which forms a square-planar nitrogen-bonded PtCl2 complex, 15. Reaction of 7 with Co2(CO)8 yields the (μ-alkyne)hexacarbonyldicobalt cluster 17, which undergoes protonation at the nitrogen atom to form 20 rather than at the alcohol to form a cobalt-complexed propargyl cation. Alkynol 7 also reacts with HBr by addition across the triple bond to form Z-9-[(2-bromo-2-phenyl)ethenyl]-4,5-diazafluoren-9-ol (10). X-ray crystal structures are reported for 6, 7, 10–15, 17 and 20, and their differing hydrogen-bonding motifs are discussed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)