Synthesis and properties of bis(pentamethylcyclopentadienyl) actinide hydrocarbyls and hydrides. A new class of highly reactive f-element organometallic compounds

Journal Article · Wed Nov 04 04:00:00 EST 1981 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00412a021· OSTI ID:5845105

Fagan, P J; Manriquez, J M; Maatta, E A; Seyam, A M; Marks, T J

The synthesis and chemical and physcochemical properties of Th and U bis(pentamethylcyclopentadienyl) chlorides, hydrocarbyls, chlorohydrocarbyls, and hydrides are reported. The reaction of the precursor compounds M(eta/sup 5/-(CH/sub 3/)/sub 5/C/sub 5/)/sub 2/Cl/sub 2/ with 2 equiv of lithium reagent RLi produces M(eta/sup 5/-(CH/sub 3/)/sub 5/)/sub 2/R/sub 2/ compounds where R = CH/sub 3/, CH/sub 2/Si(CH/sub 3/)/sub 3/, CH/sub 2/C(CH/sub 3/)/sub 3/, CH/sub 2/C/sub 6/H/sub 5/, and C/sub 6/H/sub 5/ (M = Th) and R = CH/sub 3/, CH/sub 2/Si(CH/sub 3/)/sub 3/, CH/sub 2/C/sub 6/H/sub 5/, and C/sub 6/H/sub 5/ (M = U) in good yield. With 1 equiv of lithium reagent, M(eta/sup 5/-(CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(R)Cl compounds where R = CH/sub 2/C(CH/sub 3/)/sub 3/, CH/sub 2/Si(CH/sub 3/)/sub 3/, CH/sub 2/C/sub 6/H/sub 5/, and C/sub 6/H/sub 5/ (M = Th) and R = CH/sub 2/C(CH/sub 3/)/sub 3/ CH/sub 2/Si(C/sub 3/)/sub 3/, CH/sub 2/C/sub 6/H/sub 5/, and C/sub 6/H/sub 5/, and C/sub 6/H/sub 5/ (M = U) are formed in high yield. The M(eta/sup 5/-(CH/sub 3/)/sub 5/C/sub 52/(C/sub 3/)Cl compounds can be synthesized by redistribution between the corresponding dimethyl and dichloro complexes. The new organoactinides were thoroughly characterized by elemental analysis, /sup 1/H NMR and vibrational spectroscopy, and in many cases cryoscopic molecular weight measurements. The hydrocarbyls and chlorohydrocarbyls generally exhibit high thermal stability. However, the diphenyl compounds react readily with C/sub 6/D/sub 6/ to yield, via a benzyne complex, the corresponding M(C/sub 6/D/sub 5/)/sub 2/ compounds. The Th bis(neopentyl) complex reacts with benzene to produce the corresponding diphenyl complex. Competition experiments at -78/sup 0/C indicate that the Th complexes are more reactive than those of U. The M(eta/sup 5/-(CH/sub 3/)/sub 5/))/sub 2/R/sub 2/ compounds undergo hydrogenolysis to yield organoactinide hydrides, (M(eta/sup 5/-(CH/sub 3/)/sub 5/C/sub 5/)/sub 2/(..mu..-H)H)/sub 2/, and RH. While the Th hydride exhibits high thermal stability that of U readily (and reversibly) eliminates H/sub 2/, forming a U(III) hydride. The olefin addition and hydrogenolysis reactions of the compounds can be coupled to effect homogeneous, catalytic olefin hydrogenation.

• Research Organization: Northwestern Univ., Evanston, IL
• OSTI ID: 5845105
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 103:22; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400702* -- Radiochemistry & Nuclear Chemistry-- Properties of Radioactive Materials
ACTINIDE COMPLEXES
ALKENES
CATALYSIS
CATALYTIC EFFECTS
CHEMICAL PREPARATION
CHEMICAL REACTIONS
COMPLEXES
DATA
EXPERIMENTAL DATA
HYDROCARBONS
HYDROGENATION
INFORMATION
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANOMETALLIC COMPOUNDS
SYNTHESIS
THORIUM COMPLEXES
URANIUM COMPLEXES