Tripodal polyphosphine ligands in homogeneous catalysis. 1. Hydrogenation and hydroformylation of alkynes and alkenes assisted by organorhodium complexes with MeC(CH sub 2 PPh sub 2 ) sub 3

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Organometallics; (USA)

DOI:https://doi.org/10.1021/om00115a035· OSTI ID:6654542

Bianchini, C; Meli, A; Peruzzini, M; Vizza, F ^[1]; Frediani, P ^[2]; Ramirez, J A ^[3]

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1. ISSECC CNR, Firenze (Italy)
2. Universita degli Studi di Firenze (Italy)
3. Univ. of Valencia (Spain)

The crystal structure of the complex ((triphos)RhCl(C{sub 2}H{sub 4})) (1) has been determined by X-ray methods (triphos = MeC(CH{sub 2}PPh{sub 2}){sub 3}). The rhodium atom is coordinated to an ethylene molecule, a chlorine atom, and the triphos ligand, which occupies three fac positions of an octahedron. The Rh-C{sub 2}H{sub 4} coordination exhibits a C-C distance that is among the longest found in metal-ethylene structures (1.49 (4) {angstrom}). Compound 1 is the starting point to synthesize a number of ethylene complexes of rhodium containing hydride or {sigma}-organyl coligands: ((triphos)RhH(C{sub 2}H{sub 4})), ((triphos)Rh(C{sub 2}H{sub 5})(C{sub 2}H{sub 4})), ((triphos)Rh(CH{sub 3})(C{sub 2}H{sub 4})), ((triphos)Rh(C{sub 6}H{sub 5})(C{sub 2}H{sub 4})). All of the ethylene complexes but 1 react with CO, forming {sigma}-acyl carbonyls of general formula ((triphos)Rh(COR)(CO)) via the {sigma}-organyl carbonyls ((triphos)Rh(R)(CO)) (R = CH{sub 3}, C{sub 2}H{sub 5}, C{sub 6}H{sub 5}). Compound 1 reacts with CO, yielding the carbonyl ((triphos)RhCl(CO)). The hydrogenolysis reactions of the {sigma}-organyl ethylene complexes invariably give the trihydride ((triphos)Rh(H){sub 3}) and the corresponding hydrocarbon. In contrast, the {sigma}-acyl carbonyls and the {sigma}-organyl carbonyls react with H{sub 2} to form the hydride carbonyl ((triphos)RhH(CO)) and the corresponding hydrocarbon or aldehyde. Another excellent synthetic entry to organorhodium complexes of triphos is the {sup 3}{eta}-alkyne complex ((triphos)Rh({eta}{sup 2}-DMAD))BPh{sub 4} (DMAD = dimethyl acetylenedicarboxylate). This reacts with H{sub 2} to give the tetrahydride ((triphos)RhH({mu}-H){sub 2}HRh(triphos))(BPh{sub 4}){sub 2} and dimethyl succinate.

• OSTI ID: 6654542
• Journal Information: Organometallics; (USA), Journal Name: Organometallics; (USA) Vol. 9:1; ISSN 0276-7333; ISSN ORGND
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400200* -- Inorganic
Organic
& Physical Chemistry
ALKENES
ALKYNES
CATALYSIS
CHEMICAL REACTIONS
COMPLEXES
CRYSTAL STRUCTURE
DATA
DATA ANALYSIS
ETHYLENE
EXPERIMENTAL DATA
HYDROCARBONS
HYDROGENATION
INFORMATION
MEASURING INSTRUMENTS
MEASURING METHODS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
RHODIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES