Characterization of the anion [(.eta.5-C5H5)3 UIII-n-C4H9]-. Synthesis and crystal structure of tricyclopentadienyl n-butyluranium(III) lithium cryptate: [(C5H5)3UC4H9]-[LiC14H28N2O4]+

[{[(η7-C2B10H12)(η6-C2B10H12)U][K2(thf)5]}2]: A Metallacarborane Containing the Novelη7-C2B10H124− Ligand

“…These values are very close to those of UÀC s bonds normally observed in organouranium compounds, for instance, 2.43 (2) in [(C 5 H 5 ) 3 U(nBu)], [11] 2.56(1) in [(C 5 H 5 ) 3 U(nBu)] À , [12] 2.48(3) in [(C 5 H 5 ) 3 U{CH 3 C(CH 2 ) 2 }], [13] 2.54 (2) in [(C 5 H 5 ) 3 U(p-CH 2 C 6 H 4 CH 3 )], [11] and 2.436(4) in [(Me 3 SiC 5 H 4 ) 3 U(CH CH 2 )]. [14] The five B atoms of the C 2 B 5 bonding face are almost coplanar, and the two C atoms are about 0.6 above this plane.…”

Expanding the Family of Uranium(III) Alkyls: Synthesis and Characterization of Mixed‐Ligand Derivatives

“…Successful synthesis of the mixed‐ligand uranium(III) alkyl derivatives reported here is significant given that trivalent alkyls are relatively rare. Furthermore, the only known examples bearing cyclopentadienyl ligands are [Cp 3 U(CH 2 )CH 3 ] – , [Cp 3 UCH 3 ] – , Cp* 2 U[CH(SiMe 3 ) 2 ], and [Cp*UCH(SiMe 3 ) 2 ] 2 (µ‐η 6 : η 6 ‐C 6 H 6 ) . Thus, incorporating a more sterically demanding hydrotris(pyrazolyl)borate derivative allows for variation of the alkyl group .…”

Achievements in uranium alkyl chemistry: celebrating sixty years of synthetic pursuits

“…[Cp 3 UR] − , by treatment with one equivalent of LiR (R = n Bu (3), Me (4), Ph ( 5)) (Scheme 1). 14 In the cases of red-brown 3 and dark brown 4, gas chromatographic analysis revealed evolution of butane for both, with methane also detected for 4 as the reaction proceeds. To make 5, PhLi was added to Cp 3 U n Bu in diethyl ether-benzene; therefore benzene loss could not be detected.…”

“…Unsubstituted cyclopentadienyl ligands were initially used to generate a family of stable uranium(IV) alkyls as reported by Marks and co-workers. Treating a suspension of Cp 3 UCl in diethyl ether with three equivalents of LiR (R = Me (12), n Bu, allyl (13), neopentyl (14), C 6 F 5 , i Pr) 7 or MgXR (R = CH 3 C-(CH 2 ) 2 , 32 t Bu, 7 cis-2-butenyl, 7 trans-2-butenyl, 7 Ph, 7 vinyl (15) 7 ) at −78 °C afforded the desired products after warming to room temperature, stirring for 2 hours, and filtration to remove the LiCl or magnesium salts. 1 H NMR spectroscopic measurements (benzene-d 6 ) confirmed product formation.…”