Observations on the thermal decomposition of some uranium(IV) tetraalkyls

Marks, Tobin J.; Seyam, Afif M.

doi:10.1016/s0022-328x(00)93684-2

Cited by 63 publications

(49 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Attempts to abstract a methyl group with 1 equiv of NEt 3 HCl produce similar results (see the Supporting Information). Thus, it appears that demethylation simply results in the re-formation of [Li(TMEDA)] 3 7 Li NMR spectrum in THF-d 8 exhibits a single resonance at −0.53 ppm.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…14 The Th−C benzyl bond lengths for these ligands range from 2.59(2) to 2.69(2) Å and are comparable to the Th−C benzyl bond lengths observed in the multidentate ligands and those seen in other actinide benzyl complexes. 14,80−83 For example, The U−C benzyl distances in [K(THF)] 3 [K(THF) 2 ][U(CH 2 Ph) 6 ] 2 range from 2.50(2) to 2.57(2) Å. 19 In addition, there are four potassium cations in the asymmetric unit of 3.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

“…4 These molecules were characterized by 1 H NMR spectroscopy, magnetic susceptibility, and, where possible, elemental analysis. In addition, the reaction of excess LiR (R = Me, CH 2 t Bu, CH 2 SiMe 3 ) with U 2 (OEt) 10 in dioxane was reported to provide the uranium(V) octa(alkyl) complexes [Li(dioxane)] 3 [UR 8 ]. However, the formulation of both the uranium(IV) and -(V) complexes, in the absence of solid-state structural data, was later called into question.…”

Section: ■ Introductionmentioning

confidence: 99%

“…19 This complex is quite temperature-sensitive and decomposes rapidly above −25°C, both in solution and in the solid state. Additionally, the reaction of UCl 4 with 6 equiv of K(CH 2 Ph) in THF results in the formation of [K(THF)] 3 6 in THF (Scheme 2) cleanly generates U-(CH 2 SiMe 3 ) 6 , according to 1 H NMR spectroscopy. The solid-state molecular structure of U(CH 2 SiMe 3 ) 6 would be of significant interest; however, this material is quite thermally sensitive and rapidly decomposes above −25°C, making its isolation an experimental challenge.…”

Section: ■ Introductionmentioning

confidence: 99%

See 3 more Smart Citations

In Pursuit of Homoleptic Actinide Alkyl Complexes

Seaman

Walensky

et al. 2012

Inorg. Chem.

View full text Add to dashboard Cite

This Forum Article describes the pursuit of isolable homoleptic actinide alkyl complexes, starting with the pioneering work of Gilman during the Manhattan project. The initial reports in this area suggested that homoleptic uranium alkyls were too unstable to be isolated, but Wilkinson demonstrated that tractable uranium alkyls could be generated by purposeful "ate" complex formation, which serves to saturate the uranium coordination sphere and provide the complexes with greater kinetic stability. More recently, we reported the solid-state molecular structures of several homoleptic uranium alkyl complexes, including [Li(THF)4][U(CH2(t)Bu)5], [Li(TMEDA)]2[UMe6], [K(THF)]3[K(THF)2][U(CH2Ph)6]2, and [Li(THF)4][U(CH2SiMe3)6], by employing Wilkinson's strategy. Herein, we describe our attempts to extend this chemistry to thorium. The treatment of ThCl4(DME)2 with 5 equiv of LiCH2(t)Bu or LiCH2SiMe3 at -25 °C in THF affords [Th(CH2(t)Bu)5] (1) and [Li(DME)2][Th(CH2SiMe3)5 (2), respectively, in moderate yields. Similarly, the treatment of ThCl4(DME)2 with 6 equiv of K(CH2Ph) produces [K(THF)]2[Th(CH2Ph)6] (3), in good yield. Complexes 1-3 have been fully characterized, while the structures of 1 and 3 were confirmed by X-ray crystallography. Additionally, the electronic properties of 1 and 3 were explored by density functional theory.

show abstract

Section: ■ Results and Discussionmentioning

confidence: 99%

Section: ■ Results and Discussionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

See 2 more Smart Citations

In Pursuit of Homoleptic Actinide Alkyl Complexes

Seaman

Walensky

et al. 2012

Inorg. Chem.

View full text Add to dashboard Cite

show abstract

“…9 In the case of 2-Bn and its derivatives, stability is imparted by the η 4 -coordination of the benzyl groups, which prevent unwanted side reactions that have plagued previous synthetic attempts. 5,6,10 The successful isolation and characterization of 2-Bn demonstrated that perhaps this synthetic route could be expanded to produce organouranium species with alkylsubstituted benzyls, benzyls with functional groups, and 2-picoline. Along these lines, we targeted a general procedure to synthesize a new family of substituted benzylpotassium reagents, 1-Bn′ (Bn′ = p-i PrBn, p-t BuBn, p-NMe 2 Bn, pSMeBn, m-OMeBn, o-OMeBn, 2-picolyl), which would provide diversity in steric, electronic, and coordination environments for the resulting uranium complexes.…”

Section: ■ Introductionmentioning

confidence: 99%

New Benzylpotassium Reagents and Their Utility for the Synthesis of Homoleptic Uranium(IV) Benzyl Derivatives

et al. 2015

View full text Add to dashboard Cite

A new family of benzylpotassium reagents, KBn′(1-Bn′) (Bn′ = p-i PrBn, p-t BuBn, p-NMe 2 Bn, p-SMeBn, m-OMeBn, o-OMeBn, 2-picolyl), was synthesized using a modified literature procedure and characterized by multinuclear NMR spectroscopy. Combining four equivalents of 1-Bn′ with UCl 4 at low temperature in THF afforded the homoleptic uranium(IV) derivatives 2-Bn′ (2-p-i Pr, 2-p-t Bu, 2-p-NMe 2 , 2-p-SMe, 2-o-Picolyl, 2-m-OMe, 2-o-OMe). In addition to 1 H NMR spectroscopic characterization, structural studies of five of these organouranium compounds (2-p-i Pr, 2-p-t Bu, 2-o-Picolyl, 2-m-OMe, 2-o-OMe) were performed, showing that in many cases the benzyl groups are coordinated in an η 4 -fashion, lending stability to these otherwise low-coordinate molecules. In the cases of U(o-OMeBn) 4 (2-o-OMe) and U(2-picolyl) 4 (2-o-Picolyl), heteroatom coordination to the uranium center is observed.

show abstract

Actinides: Organometallic Chemistry

Burns¹,

Clark²,

Sattelberger³

2005

Encyclopedia of Inorganic Chemistry

View full text Add to dashboard Cite

An actinide organometallic complex is one containing an actinide‐carbon π‐bond, an actinide‐carbon σ‐bond, or a combination of both. Actinide organometallic complexes are known for the actinide (An) elements from thorium through californium; the vast majority of the reports on organoactinide compounds, however, deal with thorium and uranium. The latter elements have isotopes, for example, thorium‐232 ( t 1/2 = 1.41 × 10 10 years) and uranium‐238 ( t 1/2 = 4.468 × 10 9 years), with extremely long half‐lives. Modern organoactinide chemistry is characterized by the existence not only of actinide analogs to many classes of d transition metal complexes, but increasingly common reports of compounds and types of reactions unique to the actinide series.

show abstract

Observations on the thermal decomposition of some uranium(IV) tetraalkyls

Cited by 63 publications

References 29 publications

In Pursuit of Homoleptic Actinide Alkyl Complexes

In Pursuit of Homoleptic Actinide Alkyl Complexes

New Benzylpotassium Reagents and Their Utility for the Synthesis of Homoleptic Uranium(IV) Benzyl Derivatives

Actinides: Organometallic Chemistry

Contact Info

Product

Resources

About