A Synthetic and X-ray Crystallographic Study of Zinc and Platinum Complexes of 4,5-Diazafluoren-9-one (Dafone) and Dicobalt Hexacarbonyl Derivatives of 9-Phenylethynyl-4,5-Diazafluoren-9-ol: Chelation versus Monocoordination

作者：Maguire Linda; Seward Corey M; Baljak Sladjana; Reumann Thea; Ortin Yannick; Banide Emilie; Nikitin Kirill; Mueller Bunz Helge; McGlinchey Michael J^*

来源：European Journal of Inorganic Chemistry, 2009, 2009(22): 3250-3258.

DOI：10.1002/ejic.200900161

• Metal-nitrogen linkages
• Asymmetric bonds
• Hydrogen bonds
• Coordination modes
• Zinc
• Platinum
• Cobalt

Reaction of 4,5-diazafluoren-9-one (dafone, 6) and zinc dichloride yields [(dafone)ZnCl(2)(H(2)O)] (11) in which the ZnCl(2) moiety is coordinated to a single nitrogen atom and also to a molecule of water. Hydrogen bonding, not only to the un-complexed 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)(2)ZnI(2) (12) in which the metal-nitrogen distances - 2.170(5) and 2.456(5) angstrom - are significantly different. Dafone, in the presence of dimethyl sulfoxide, reacts with K(2)PtCl(4) to produce square-planar (dafone)PtCl(2)(dmso) (13), whereas with K(2)PtBr(6) the octahedral complex (dafone)PtBr(4) (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 PtCl(2) complex, 15. Reaction of 7 with Co(2)(CO)(8) yields the (mu-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.

• 出版日期2009-8