A dimeric niobium(I) complex formed by electrochemical reduction of a niobium(III) dimethylphosphane adduct

✍ Scribed by Liliane G. Hubert-Pfalzgaf; Annie Chaloyard; Nabil El Murr

• Book ID: 104138968
• Publisher: Elsevier Science
• Year: 1982
• Tongue: English
• Weight: 216 KB
• Volume: 65
• Category: Article
• ISSN: 0020-1693
• DOI: 10.1016/s0020-1693(00)93535-7

✦ Synopsis

The molecular chemistry of niobium in oxrdatron states lower than 3 is very limited, especially for noncarbonyl derivatives [ 11. In fact, the only niobium(I) species reported so far are an impure dinitrogen compound {NbCl(dmpe)z}(p-Nz)

[2] (dmpe = 1,2-brs-(dimethylphosphino)ethane) and an ally1 derivative, ($-CHaCgHq)(CqH6)2Nb

[3] obtained by metal vapor synthesis. On the other hand, the unstable CpzNb, which could not be isolated, was characterized only by its EPR spectra and by its derivatives resulting from oxidative addition reactions [4] ; this suggests a low stability for oxidation state 2.

Starting from the niobium(II1) complex Nb2C16-(PhPMe.& for which a metal-metal bond of order 2 was assumed [S], we undertook electrochemical investigations in order to gain more information about the relative stability of oxidation states 2 and 1 and to generate stable niobium species having triple or quadruple metal-metal bonding. We now report the salient features of this investigation.