Crystal Structure of a Carbonylation Catalyst: Acetyldiiodo-1,3-bis(diphenylphosphino)propanerhodium(III).

Comparison of the Thermal and Reductive Decarbonylation of a Rhodium Trifluoroacetyl Diphosphine Complex

“…Contact between the acyl oxygen and the phosphorus atoms in 1 and the single F2 atom and the phosphorus atoms in 3 is less significant, and so those angles are closer to the ideal 90° value. These slight distortions are quite typical of this class of rhodium complexes and agree with several related structures that we have solved, as well as literature reports for similar dichloro complexes. , Interestingly, Moloy and Petersen’s reported structure for Rh(dppp)(COCH 3 )I 2 shows significant distortion toward a trigonal bipyramid, but Søtofte and Hjortkjær have reported the structure as having only minor deviations from square-pyramidal geometry . We have independently solved the structure of this compound and found it in agreement with that of 1…”

“…This complex was characterized by IR, NMR, elemental analysis, and X-ray crystallography (Figure , Table ). As with previously reported rhodium acyl complexes of this type, ,− complex 1 adopts an essentially square-pyramidal geometry with the trifluoroacetyl group in the apical position. Other than the somewhat enlarged C−Rh−I bond angles, the structure is an essentially ideal square pyramid (vide infra).…”

“…3,22 Interestingly, Moloy and Petersen's reported structure for Rh(dppp)(COCH 3 )I 2 shows significant distortion toward a trigonal bipyramid, 21 but Søtofte and Hjortkjaer have reported the structure as having only minor deviations from square-pyramidal geometry. 24 We have independently solved the structure of this compound and found it in agreement with that of 1. 36 The bond lengths in complexes 1 and 3 are quite typical.…”

[1,3-Bis(diphenylphosphino)propane-κ2P,P′]diiodido(perfluoropropyl)rhodium(III) dichloromethane solvate

“…The geometry about the rhodium atom is square-based pyramidal (sbp) with the perfluoropropyl group occupying the axial position. This geometry is similar to that of trans-Rh(CF 2 H) (PPh 3 ) 2 Cl 2 (Burrell et al, 1990), cis-Rh(COMe)(dppp)I 2 , where dppp = 1,3-bis(diphenylphosphino)propane (Søtofte & Hjortkjaer, 1994), cis-Rh(COPh)(dppp)Cl 2 (McGuiggan et al, 1980), trans-Rh(COCH 2 CH 2 Ph)(PPh 3 ) 2 Cl 2 (Egglestone et al, 1977), and cis-Rh(COCH 2 CH 3 )(PPh 3 ) 2 Cl 2 (Shie et al, 1989), without the significant distortion toward trigonal bipyramidal geometry reported for cis-Rh(COCH 3 )(dppp)I 2 by Moloy & Petersen (1995). The structure of the title compound includes one CH 2 Cl 2 solvent molecule, not shown in Fig.…”

Reactivity of cationic methyl rhodium(III) complexes cis-[Rh(β-diket)(PPh3)2(CH3)(CH3CN)][BPh4] toward ligands of different character: pyridine, carbon monoxide, and triphenylphosphine

“…By analogy, we assign the signals at d 2.47 (3H) and 1.85 ppm (3H) in the spectrum of complex 3 to methyl groups of acetyl and benzoylacetonate ligands, respectively. It is easy to verify that a trigonal bipyramid with trans-phosphines and the acetyl group in the equatorial position fits all the experimental data: Acyl complexes of rhodium(III) usually exist in a pentacoordinate form, and their typical solid-state geometry is square pyramid (sp) with apical acyl ligand [4,9,10,[18][19][20][21][22][23]. The same geometry was evidenced for these complexes in solutions.…”