Borole derivatives.: 24.: Synthesis of cationic (Arene)(phenylborole)rhodium complexes.: Structures of the trinuclear complex (η5-C4H4BPh)Rh(μ3-I)3-Rh(μ,η5:η6-C4H4BPh)Rh(η5-C4H4BMe)•CH2Cl2 and of the polymeric catena-(μ,η5:η6-1-phenylborole)rhodium tetrafluoroborate

The heterocubane [Rh(mu(3)-I)(C4H4BPh)](4) (1) reacts with Ag+ salts in acetonitrile to give the labile salt [Rh(NCMe)(3)(C4H4BPh)]BF4 (2). This salt 2 reacts with hexamethylbenzene (hmb) to give the arene complex [Rh(C4H4BPh)(hmb)]BF4 (3), and with mesitylene [Rh(1,3,5-C6H3Me3)(C4H4BPh)]BF4 (4) is obtained. Complex 2 loses acetonitrile under vacuum to produce the polymeric salt catena-[{Rh(mu,eta(5):eta(6)-C4H4BPh)}BF4](x) (5). Insight into the essential structural features of this polymer provided its radial distribution function obtained from a wide-angle X-ray scattering experiment, When treated with acetonitrile, complex 5 regenerates 2 and with pyridine affords [Rh(py)(3)((C4H4BPh)]BF4 (6). Crystallization from a solution of [Rh(mu(3)-I)(C4H4BPh)](4) (1) and the corresponding methylborole complex [Rh(mu(3)-I)(C4H4BMe)](4) (1/1) in CH2Cl2 produces the trinuclear complex (eta(5)-C4H4BPh)Rh(mu(3)-I)(3)Rh(mu,eta(5): eta(6)-C4H4BPh)Rh(eta(5)-C4H4BMe). CH2Cl2 (7) with a bridging mu,eta(5):eta(6)-C4H4BPh ligand; complex 7 was characterized by an X-ray structure determination, The resulting molecular structure was used to create a structure model for the monomeric building block of polymer 5.