Side-on dihapto-bonding of hydrazide(1–) and diazenide(1–) to titanium

Abstract

The complexes [Ti(n-C5H5)CI2L] (L = N-NPh or NPhNH2) have been shown by X-ray crystallography to contain side-on dinitrogen moieties, the former being the first example of this kind of co-ordination of a diazenido-ligand.

Assembly of an R3N52− Chain by Cycloaddition of a Hydrazinediide and an Azide at Zirconium and its Thermal Fragmentation

“…The mesityl-N 2 unit is a rare example of a nonbridging side-on-coordinated alkyl-or aryldiazenido ligand. [14] A similar h 2 -RN 2 coordination was reported for the titanium complex [Ti(C 5 H 5 )Cl 2 (h 2 -N 2 Ph)] (NÀN 1.215 (8) ) [15] as well as the nickel complex [(dtbpe)Ni(h 2 -N 2 C 6 H 4 OMe)] (dtbpe = 1,2-bis(di-tert-butylphosphino)ethane; N À N 1.224(3) ). [16] The bonding in complex 5 was modeled in a DFT (B3PW91) study.…”

Photolysis of Isoelectronic Ruthenium Nitrosyl and Diazonium Complexes in Frozen PVC Matrices: Retention of Dinitrogen on Ruthenium Following Photochemical Phenyl Radical Loss

“…[5,6] Our attention has recently turned to the photochemistry of diazonium complexes as an extension of our ongoing study of the nitrosyl ligand. Initial findings from this work indicate that in a PVC matrix at cryogenic temperatures has permitted direct observation of an isotopically sensitive product band that may be assigned to a 17-electron ruthenium dinitrogen species, suggesting that this photochemical decomposition does not proceed through formation of a diazenyl intermediate but through homolytic cleavage of the parent diazonium complex to give the phenyl radical and the 17-electron RuCl 3 …”

“…[9][10][11][12][13][14][15][16][17][18][19][20][21] Scheme 2. Mechanism for phenyl radical formation proposed by Kunkely and Vogler. In light of the report by Kunkely and Vogler, we thought it fruitful to carry out low temperature photolyses of RuCl 3 , respectively [23,24] Photolysis of RuCl 3 (NO)(PPh 3 ) 2 in PVC matrices at 85 K with λ irr = 500 ± 50 nm results in bleaching of the parent nitrosyl band at 1873 cm -1 and appearance of a photoproduct absorption at 1748 cm -1 (Δν = 125 cm -1 ), see Figure 1 (a). Photolysis at shorter wavelengths, 330 < λ irr < 400 nm, increases the extent of conversion between these two species but does not result in the appearance of any additional product bands.…”

“…A side-on linkage isomer is also known (Scheme 1, c) and several such derivatives, have been isolated. [2][3][4] Despite the similarities between the nitrosyl and arylazo ligands, the photochemistry of arylazo complexes has largely gone unexplored since the discovery of this class of compounds by King and Bisnette in 1964. [5,6] Our attention has recently turned to the photochemistry of diazonium complexes as an extension of our ongoing study of the nitrosyl ligand.…”

“…This may suggest that N-Ph homolysis is not directly occurring in the excited state, but rather as the result of vibrational relaxation of the excited state species. While phenyldiazonium salts are well known to undergo reductive dediazotization by a variety of metal reducing agents to yield aryl radicals, RuCl 3 undergo photochemical charge transfer initiated phenyl radical loss with retention (at least at cryoscopic temperatures) of the dinitrogen group.…”