Nitrogen atom transfer and redox chemistry of terpyridyl phosphoraniminato complexes of osmium (IV)

(Nitrido)ruthenium(VI) and ‐osmium(VI) Complexes with Catecholate Auxiliaries: Synthesis, Structure, and Conversion into a (Phosphoraniminato)osmium(V) Complex

“…Complex 3 has an Os(1)−N(1) distance of 2.077(3) Å and an N(1)−P(2) distance of 1.616(3) Å. These Os−N(phosphoraniminato) and N−P distances are similar to those in trans ‐[Os IV (NPPh 3 )(tpy)Cl 2 ]PF 6 and cis ‐[Os IV (NPPh 2 Me)(tpy)Cl 2 ]PF 6 ,45 but considerably longer than those in [Os IV (NPPh 3 )(salophen)Cl]32 and [Os IV (NPPh 3 )(L)Cl 2 ]46 (see Table 4). The Os− N −PPh 3 angle in 3 is 128.7(2)°.…”

“…The formation of a (phosphoraniminato)osmium( V ) complex from the reaction of a (nitrido)osmium( VI ) complex with phosphane is unusual. Previous reactions of (nitrido)osmium( VI ) complexes, such as [Os VI NX 4 ] − (X = Cl, Br),3,4 [Os VI N(tpy)Cl 2 ] + (tpy = 2,2′:6′,2′′‐terpyridine),45 [Os VI N(L)Cl] (L = salen and its derivatives),32 and [Os VI N(L)Cl 2 ] (L = [Co(η 5 ‐C 5 H 5 ){PO(OEt) 2 } 3 ] − )31,46 all gave (phosphoraniminato)osmium( IV ) and, much less frequently, (phosphoraniminato)osmium( III ) complexes. Meyer and co‐workers reported that electrochemical oxidation of trans ‐[Os IV (NPPh 3 )(tpy)Cl 2 ] + presumably gave trans ‐[Os V (NPPh 3 )(tpy)Cl 2 ] 2+ but this (phosphoraniminato)osmium( V ) species was not isolated or characterized.…”

Osmium(iv) complexes TpOs(X)Cl2 and their Os(iii) counterparts: oxidizing compounds with an unusual resistance to ligand substitution

“…Similar reductive substitution has been reported for the analogous terpyridine derivative trans-[(tpy)Os IV (NPPh 3 )Cl 2 ]PF 6 , which converts to [(tpy)Os III Cl 2 (NCCH 3 )]PF 6 on addition of HBF 4 in MeCN. 13 The source of the reducing equivalents in these reactions is not known. Reaction 5 eliminates the use of TpOs(OTf )Cl 2 , but purification of the resulting products is complicated by Ph 3 PO in the reaction mixtures.…”

Synthesis and Characterization of the Keggin‐Type Ruthenium‐Nitrido Derivative [PW11O39{RuN}]4‐ and Evidence of Its Electrophilic Reactivity.

“…The N1-P2A or N1-P2B distances of 1.487(18) and 1.511(18) Å are a bit shorter than those reported in osmium-phosphoraniminato complexes that fall in the range 1.59-1.66 Å. 7 The M-N-P link, which can be either linear or bent is clearly bent here with P2A-N1-Ru1 and P2B-N1-Ru1 angles respectively of 137.1 (11) and 139.1(11)°.…”

“…Despite the encountered disorder, the geometrical parameters around N1 and the phosphorous atoms P2A and P2B are similar to those described in the literature for osmiumphosphoraniminato function. 7 Structural characterisation of analogous ruthenium complexes are indeed unprecedented. The Ru1-N1 bond length of 1.923(16) Å, considerably elongated by comparison with a ruthenium-nitrido function, is nevertheless indicative of a multiple bonding.…”