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The complex trans-[Rh(CF3)(CNXy)2(PPh3)] (1) reacts with SO2, tetracyanoethylene (TCNE), or maleic anhydride (MA) to give the complexes [Rh(CF3)(CNXy)2(PPh3)L] (L = SO2 (2), TCNE (3), MA (4)) and with CO or CF3CO2H to give, respectively, mixtures containing mainly [Rh(CF3)(CNXy)2(CO)(PPh3)] or trans-[Rh(CNXy)2(PPh3)2]CF3CO2, which is prepared in better yield by reaction of trans-[RhCl(PPh3)2(CO)] with XyNC and NaCF3CO2. [Rh(CF3)(CNXy)3] (6) is prepared by reaction of [Rh(CF3)(CNXy)3(PPh3)] (7) with 35% H2O2 or, better, by reaction of [Rh(μ-OH)(COD)]2 with XyNC and Me3SiCF3. The reaction of 6 with tetracyanoethylene (TCNE) or maleic anhydride (MA) gives the complexes [Rh(CF3)(CNXy)3L] (L = TCNE (8), MA (9)). The oxidative addition reaction of MeI or n-C4F9I with complex 6 gives the octahedral Rh(III) complexes [Rh(CF3)(R)I(CNXy)3] (R = Me (10), n-C4F9 (11)). In an attempt to obtain single crystals of complex 11, a few crystals of [{Rh(CF3)(n-C4F9)(CNXy)2}2(μ-I)2] (12) were obtained. The crystal structures of complexes 2−4 and 12 have been determined by X-ray diffraction studies.

The rhodium(I) fluoro complexes [RhF(COD)(PR3)] (R = Ph (1a), C6H4OMe-4 (1b), i-Pr (1d), Cy (1e); COD = 1,5-cyclooctadiene) react with Me3SiRF to afford the rhodium(I) perfluoroalkyl complexes [Rh(RF)(COD)(PR3)] (RF = CF3, R = Ph (2a), C6H4OMe-4 (2b), i-Pr (2d), Cy (2e); RF = n-C3F7, R = Ph (2c)), of which 2a,c were isolated as pure solids. [Rh(CF3)(NBD)(PPh3)] (3) was prepared by reaction of 2a with norbornadiene. The reactions of 2a−c with 2,6-dimethylphenyl isocyanide (XyNC) or t-BuNC, in a 1:2 molar ratio, gave the compounds trans-[Rh(RF)(CNR‘)2(PR3)] (RF = CF3, R‘ = Xy, R = Ph (4a), C6H4OMe-4 (4b); RF = CF3, R‘ = t-Bu, R = Ph (4a‘); RF = n-C3F7, R‘ = Xy, R = Ph (4c)). The reactions of 2a−c with an equimolar amount of XyNC gave mixtures containing complexes 4a−c as the major products. The peroxo complexes [Rh(CF3)(η²-O2)(CNXy)2(PR3)], (R = Ph (7a), C6H4OMe-4 (7b)) were isolated by reacting O2 with 4a,b, respectively. The complexes [Rh(RF)(CNR‘)3(PR3)] (RF = CF3, R‘ = Xy, R = Ph (8a), C6H4OMe-4 (8b); RF = n-C3F7, R‘ = Xy, R = Ph (8c)) were obtained by reaction of 2a−c with 3 equiv of XyNC. Formation of [Rh(CF3)(PPh3)(CO)3] (9) in the reaction of complex 2a with CO was spectroscopically observed. The crystal structures of complexes 4a, 7a, and 8a have been determined by single-crystal X-ray diffraction studies. The dynamic behavior in solution of the prepared complexes was studied by variable-temperature NMR.