Multinuclear NMR studies of the products resulting from the reaction of pyridine or 2,2'-bipyridine with [Rh4(CO)12]

Kerry J Bradd; Brian T Heaton; Jonathan A Iggo; Chacko Jacob; Jeyagowry T Sampanthar; Stefano Zacchini

doi:10.1039/b715139j

Multinuclear NMR studies of the products resulting from the reaction of pyridine or 2,2'-bipyridine with [Rh4(CO)12]

Dalton Trans. 2008 Feb 7:(5):685-90. doi: 10.1039/b715139j. Epub 2007 Nov 22.

Authors

Kerry J Bradd¹, Brian T Heaton, Jonathan A Iggo, Chacko Jacob, Jeyagowry T Sampanthar, Stefano Zacchini

Affiliation

¹ Chemistry Department, University of Liverpool, UK.

PMID: 18217125
DOI: 10.1039/b715139j

Abstract

The progressive addition of anhydrous pyridine, (py), to a solution of [Rh(4)(CO)(12)] in CH(2)Cl(2) under CO, even at low temperature, results in immediate disproportionation to give cis-[Rh(CO)(2)py(2)][Rh(5)(CO)(15)]; further addition of pyridine results in the progressive replacement of CO's by py on the same apical rhodium in [Rh(5)(CO)(15)](-) to give cis-[Rh(CO)(2)py(2)][Rh(5)(CO)(15-x)py(x)] (x = 1, 2). The analogous reactions with 2,2'-bipyridine (bipy) give only [Rh(CO)(2)bipy][Rh(5)(CO)(13)bipy]. IR and low temperature, multinuclear NMR measurements have been used to establish the structures of all the above anions and the structures of [Rh(5)(CO)(13)(bipy)](-) and [Rh(5)(CO)(13)py(2)](-) are subtly different. Under N(2), [Rh(4)(CO)(12)] reacts with py to give [Rh(6)(CO)(16-y)py(y)] (y = 1, 2).