Polarographic evidence of the formation of a uni-negative bipyridyl complex of cobalt in dimethylformamide

✍ Scribed by S.K. Dhar; Wayne E. Kurcz

• Book ID: 104149809
• Publisher: Elsevier Science
• Year: 1974
• Weight: 187 KB
• Volume: 53
• Category: Article
• ISSN: 0022-0728
• DOI: 10.1016/s0022-0728(74)80145-2

✦ Synopsis

In a recent paper Musumecl et al.' described the polarographic reduction of bis(2,2',2"-terpyridine)cobalt(lI) perchlorate in acetonitrile to its zerovalent form [Co(terp)2]. Formally zerovalent [Co(bipy)3] is also reported in the literature 2, as well as the uni-negative Co(CO)~7 ion 3. However, no reference of a uni-negative bipyridyl complex was found. In this communication we present evidences to indicate the formation of such a complex by the reduction of Co(bipy)~ ÷ at a dropping mercury electrode in dimethylformamide (DMF). Experimental Polarography of Co(NO3)2 in the presence of excess bipyridine in DMF, gave identical polarograms with those of Co(bipy)32 in the absence or presence of added bipyridine (Fig. 1B). However, added bipyridine was necessary in the -2.1 -1.8 -1.5 -1.2 > -o.g -0.(~ -0.3 0.0