Synthesis, X-ray, crystal structure, and electrochemical properties of the Rh/sub 2//sup 4 +/ complex Rh/sub 2/(form)/sub 4/ (form = N,N'-Di-p-tolylformamidinate anion)

Journal Article · Wed Jul 15 04:00:00 EDT 1987 · Inorg. Chem.; (United States)

DOI:https://doi.org/10.1021/ic00261a009· OSTI ID:5522704

Piraino, P; Bruno, G; Schiavo, S L; Laschi, F; Zanello, P

The reaction of the dirhodium(II) mixed-ligand complex Rh/sub 2/(form)/sub 2/(O/sub 2/CCF/sub 3/)/sub 2/(H/sub 2/O) (form = N,N'-di-p-tolylformamidinate anion) with free N,N'-di-p-tolylformamidine (mole ratio 1:4) leads to the formation of the complex Rh/sub 2/ (form)/sub 4/ (1) in excellent yield. The complex was characterized by a single-crystal X-ray diffraction analysis, crystallizing in the space group Pnanti3n, with a = 20.990 (2) A, V = 9248 A/sup 3/, Z = 6, R = 0.036, and R/sub w/ = 0.0378. The Rh-Rh (2.4336 (4) A) and the Rn-N (2.050 (5) A) bond distances are well in the range observed for this class of compounds. The molecule is in a staggered conformation, with N-Rh-Rh-N torsion angles of 16.7 (2)/sup 0/. Complex 1 reacts with carbon monoxide, giving the monocarbonyl adduct Rh/sub 2/-(form)/sub 4/(CO) (2), characterized by elemental analysis and IR, /sup 13/C NMR, and electrochemical measurements. Unlike other dirhodium(II) carbonyl derivatives, 2 is remarkably stable. In the /sup 13/C NMR spectrum a dramatic upfield shift is seen for the carbonyl resonance (delta 144.06); the IR spectrum shows v(CO) at 2040 cm/sup -1/. These data coupled to electrochemical measurements suggest that the ..pi.. back-bonding is reasonably strong in 2. The electrode behavior of 1 has been investigated in different nonaqueous solvents.

• Research Organization: Universita di Messina, Italy
• OSTI ID: 5522704
• Journal Information: Inorg. Chem.; (United States), Journal Name: Inorg. Chem.; (United States) Vol. 26:14; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400400 -- Electrochemistry
AMIDES
CHEMICAL PREPARATION
CHEMISTRY
COHERENT SCATTERING
COMPLEXES
CRYSTAL STRUCTURE
DATA
DIFFRACTION
ELECTROCHEMISTRY
EXPERIMENTAL DATA
INFORMATION
INFRARED SPECTRA
MAGNETIC RESONANCE
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
RESONANCE
RHODIUM COMPLEXES
SCATTERING
SPACE GROUPS
SPECTRA
SYNTHESIS
TRANSITION ELEMENT COMPLEXES
X-RAY DIFFRACTION