Dicarbonyl(acetylacetonato)rhodium(I)

Dicarbonyl(acetylacetonato)rhodium(I) is an organorhodium compound with the formula Rh(O₂C₅H₇)(CO)₂. The compound consists of two CO ligands and an acetylacetonate. It is a dark green solid that dissolves in acetone and benzene, giving yellow solutions. The compound is used as a precursor to homogeneous catalysts.^[2]

Dicarbonyl(acetylacetonato)­rhodium(I)

Names
Other names Rhodium acetylacetonate dicarbonyl
Identifiers
CAS Number	14874-82-9
3D model (JSmol)	coordination form: Interactive image ionic form: Interactive image
ChemSpider	9055018
ECHA InfoCard	100.035.392
PubChem CID	10879749
InChI InChI=1S/C5H8O2.2CO.Rh/c1-4(6)3-5(2)7;2*1-2;/h3,6H,1-2H3;;;/b4-3+;;; Key: GGRQQHADVSXBQN-FHJHGPAASA-N
SMILES coordination form: CC(=C[C-](C)O1)O[Rh+]1(C#[O])C#[O] ionic form: C/C(=C/C(=O)C)/[O-].[C-]#[O+].[C-]#[O+].[Rh+]
Properties
Chemical formula	C7H7O4Rh
Molar mass	258.034 g·mol−1
Appearance	green solid
Density	1.95 g/cm3
Melting point	155 °C (311 °F; 428 K)
Structure[1]
Crystal structure	triclinic
Space group	P1
Lattice constant	a = 6.5189 Å, b = 7.7614 Å, c = 9.205 Å α = 106.04°, β = 91.15°, γ = 100.21° at 20°C
Lattice volume (V)	439.3 Å3
Formula units (Z)	2
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

It is prepared by treating rhodium carbonyl chloride with sodium acetylacetonate in the presence of base:^[3]

[(CO)₂RhCl]₂ + 2 NaO₂C₅H₇ → 2 Rh(O₂C₅H₇)(CO)₂ + 2 NaCl

The complex adopts square planar molecular geometry. The molecules stack with Rh---Rh distances of about 326 pm. As such, it is representative of a linear chain compound.^[1]

Portion of the lattice of Rh(acac)(CO)₂ showing the "stacking" of the individual planar units through Rh---Rh interactions.