Organoactinide carbonylation and carboxylation chemistry. Structural, electronic, bond energy, and photochemical effects on migratory insertion in the tris(cyclopentadienyl)thorium hydrocarbyl series

Journal Article · Wed Jun 13 04:00:00 EDT 1984 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00324a016· OSTI ID:6454103

Sonnenberger, D C; Mintz, E A; Marks, T J

A synthetic and kinetic study of CO migratory insertion is reported for the series of thorium hydrocarbyls Th(eta/sup 5/-C/sub 5/H/sub 5/)/sub 3/R, R = i-C/sub 3/H/sub 7/, sec-C/sub 4/H/sub 9/, neo-C/sub 5/H/sub 11/, n-C/sub 4/H/sub 9/, CH/sub 2/Si(CH/sub 3/)/sub 3/, CH/sub 3/, and CH/sub 2/C/sub 6/H/sub 5/. Under the conditions employed, the reaction was found to be first order in Th(C/sub 5/H/sub 5/)/sub 3/R and first order in CO. In the above order, the relative rates of migratory insertion were found to be 42:18:1.3:1.0:0.02:0.01:<0.01. In the case of R = CH/sub 3/, i-C/sub 3/H/sub 7/, n-C/sub 4/H/sub 9/, neo-C/sub 5/H/sub 11/, and sec-C/sub 4/H/sub 9/, carbene-like (by spectroscopic and chemical properties) eta/sup 2/-acyl insertion products, Th(C/sub 5/H/sub 5/)/sub 3/(eta/sup 2/-COR), could be isolated and characterized. In the case of R = i-C/sub 3/H/sub 7/ and CH/sub 2/Si(CH/sub 3/)/sub 3/, enolate rearrangement products were isolated and characterized. The relative rates of CO insertion reflect both steric and electronic effects; there is a significant correlation with experimentally determined Th-R bond disruption enthalpies. For Th(C/sub 5/H/sub 5/)/sub 3/CH/sub 2/Si(CH/sub 3/)/sub 3/, it was also found that the rate of migratory CO insertion could be significantly accelerated by photolysis. However, secondary reactions of the insertion product are also observed. A comparative study of CO/sub 2/ migratory insertion to yield bidentate carboxylates revealed that carboxylation is significantly slower than carbonylation (a factor of 50 for Th(C/sub 5/H/sub 5/)/sub 3/CH/sub 3/; a factor of 10/sup 5/ for Th(C/sub 5/H/sub 5/)/sub 3/(i-C/sub 3/H/sub 7/)) and that for the above two compounds sensitivity of the rate to the nature of R is considerably altered vis-a-vis CO migratory insertion. 51 references, 2 figures, 2 tables.

• Research Organization: Northwestern Univ., Evanston, IL
• OSTI ID: 6454103
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 106:12; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702* -- Radiochemistry &amp; Nuclear Chemistry-- Properties of Radioactive Materials
ACTINIDE COMPLEXES
ALKANES
ALKENES
AROMATICS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON MONOXIDE
CARBON OXIDES
CARBONYLATION
CARBOXYLATION
CHALCOGENIDES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPARATIVE EVALUATIONS
COMPLEXES
CYCLOALKENES
DATA
DECOMPOSITION
DIENES
EXPERIMENTAL DATA
HYDROCARBONS
INFORMATION
INFRARED SPECTRA
KINETICS
LIGANDS
NMR SPECTRA
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
POLYENES
REACTION KINETICS
SILICON COMPOUNDS
SPECTRA
STRUCTURAL CHEMICAL ANALYSIS
THORIUM COMPLEXES