228549-20-0

Upstream product

• 882-33-7 diphenyldisulfane 
• 410076-79-8 [(η5-pentamethylcyclopentadienyl)2U(μ-Ph)2BPh2] 
• 948574-18-3 (C₅Me₅)2UMe(SPh) 
• 190076-36-9 tris(pentamethylcyclopentadienyl)uranium(III) 
• 108-98-5 thiophenol 

Downstream Products

• 362631-25-2 Na[Cp*2U(SPh)2] 

Relevant academic research and scientific papers

Multi-electron reduction from alkyl/hydride ligand combinations in U 4+ complexes

The U4+ mixed alkyl hydride complex (C5Me5)U[μ-C5Me3(CH2)2](μ-H)2U(C5Me5)2, 1, which contains a cyclopentadienyl ligand with two metalated methylene substituents, can effect four, six, and eight-electron reductions in which the combination of the two H1- ligands and the [C5Me3(CH2)2]3- moiety delivers four electrons and forms (C5Me5)1-. The reaction is formally equivalent to an alkyl hydride reductive elimination, a transformation common with transition metals not previously observed with f element compounds. This type of alkyl hydride reduction reactivity is also observed with a combination of U4+ alkyl and hydride complexes, (C5Me5)2UMe2/[(C5Me5)2UH2]2, which reduces benzene to make [(C5Me5)2U]2(C6H6), a U3+ complex formally containing a (C6H6)2- ligand. Copyright

(η5-C5Me5)2U(=P-2,4,6-tBu3C6H2)(OPMe3) Revisited-its intrinsic reactivity toward small organic molecules

The Lewis base stabilized uranium phosphinidene (η5C5Me5)2U(=P-2,4,6-tBu3C6H2)(OPMe3) (2), which was derived from (η5-C5Me5)2U(Cl)Me (1) and 2,4,6-(Me3C)3C6H2PHK in toluene in the presence of Me3PO, was originally reported in 1996, but since then its reactivity toward small organic molecules has not been extensively explored. This contribution closes this gap, and divergent reactivity patterns are established in the reaction of complex 2 toward (small) organic substrates. For example, complex 2 may release the phosphinidene moiety (2,4,6-tBu3C6H2P:) and therefore may act as a source of a (η5C5Me5)2UII fragment in the presence of Ph2S2, Ph2Se2, bipy, ketazine (Ph2C=N)2, and conjugated alkynes RC=CC=CR, forming the disulfido compound (η5-C5Me5)2U(SPh)2 (5), diselenido compound (η5-C5Me5)2U(SePh)2 (6), bipy compound (η5-C5Me5)2U(bipy) (8), diiminato compound (η5-C5Me5)2U(N=CPh2)2 (9) and the metallacyclopentatrienes (η5-C5Me5)2U[η4-C4(R)2] (R = Ph (10), Me3Si (11)), respectively. Furthermore, compound 2 may also straightforwardly react with terminal alkynes and a variety of heterounsaturated (organic) molecules such as CS2, isothiocyanates, imines, diazenes, carbodiimides, nitriles, isonitriles, and organic azides. For instance, on treatment with phenylacetylene (PhC=CH) the dialkynyl uranium complex (η5-C5Me5)2U(C2Ph)2(OPMe3) (12) is formed, whereas CS2 and PhNCS furnish the carbodithioates (η5-C5Me5)2U[SC(=P-2,4,6-tBu3C6H2)S](OPMe3) (13) and (η5-C5Me5)2U[SC(=NPh)S](OPMe3) (14), respectively. In the reaction of the secondary aldimine PhCH= NPh or the diazene PhN=NPh and 2 the uranium(IV) imido complex (η5-C5Me5)2U(=NPh)(OPMe3) (15) is isolated, which is in contrast to its reactivity with the primary ketimine 9-(C12H8)C=NH and the carbodiimides (RN=)2C, yielding the diiminato uranium(VI) complex (η5-C5Me5)2U[N=C(C12H8)]2 (16) and the four-membered uranaheterocycles (η5-C5Me5)2U[N(R)C(=P-2,4,6-tBu3C6H2)N(R)] (R = C6H11 (17), iPr (18)), respectively. Furthermore, treatment of 2 with nitriles RCN affords the imido uranium(IV) complexes (η5-C5Me5)2U[=NC(=P-2,4,6-tBu3C6H2)R](OPMe3) (R = C6H11 (19), Me3C (20)), whereas isonitriles RNC furnish the metallaaziridines (η5-C5Me5)2U[C(=P-2,4,6-tBu3C6H2)N(R)](OPMe3) (R = C6H11 (21), 2,6-Me2Ph (22)). However, in the reaction with organic azides RCN3, complex 2 yields the imido uranium(IV) complexes (η5-C5Me5)2U(= NR)(OPMe3) (R = Ph3C (23), p-tolyl (24)) as a result of 3,3-Me2-5,7-tBu2C8H5P (7) formation and N2 release. The new compounds 12-24 were characterized by various spectroscopic techniques, including single-crystal X-ray diffraction analyses. Furthermore, with complex 2 in hand a comparison between the reactivity of uranium phosphinidenes differing in the steric bulk of its cyclopentadienyl ligands and the effects of a Lewis base (OPMe3) adduct was undertaken.

Sigma bond metathesis with pentamethylcyclopentadienyl ligands in sterically crowded (C5Me5)3M complexes

To further explore the reactivity of the (C5Me5) - ligand in the sterically crowded (C5Me5) 3M complexes, reactions with PhEEPh (E = S, Se, Te) have been examined. With M = La, Pr, Nd, Sm, and Y, PhSSPh reacts to form the expected reduction products, [(C5Me5)2M(SPh)] 2, but the major organic byproduct is not the sterically induced reduction product, (C5Me5)2. Instead, the sigma bond metathesis product, C5Me5SPh, is the major byproduct. In contrast, reactions with (C5Me5) 3Ce and (C5Me5)3U gave a mixture of C5Me5SPh and (C5Me5)2 as byproducts. PhSSPh reactions with the lanthanide nitrile adducts, (C 5Me5)3Ln(NCCMe3)2 (Ln = La, Ce) and (C5Me5)3Nd(NCCMe3), formed [(C5Me5)2Ln(SPh)(NCCMe 3)]2 and only C5Me5SPh as the byproduct. PhSeSePh reactions paralleled the PhSSPh results, but reactions of PhTeTePh with (C5Me5)3La, (C5Me 5)3Sm, and (C5Me5) 3La(NCCMe3)2 gave only (C5Me 5)2 as a byproduct. The Royal Society of Chemistry 2010.

Reactivity of tuck-in and tuck-over uranium metallocene complexes

The reactivity of the uranium tuck-in and tuck-over cyclopentadienyl moieties {[ν5:ν1-C5Me4CH 2]U}2+ and {U[μ- ν5:ν1- C5Me4CH2]U}6+, respectively, has been investigated by examining the reactivity of (C5Me 5)U[μ- ν5:ν1:ν1-C 5Me3(CH2)2](μ-H) 2U(C5Me5)2, 1, and (C 5Me5)(ν5:ν1-C 5Me4CH2)(hpp)U [(hpp)- = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidinato], 2, with hydrogen, silyl halide, sulfide, amine, and hydrocarbon reagents. The reactivity of 2, which has a single tuck-in reactive site, provides valuable comparisons with that of 1, where the presence of two hydride ligands as well as both tuck-in and tuck-over moieties leads to products in which multiple transformations have occurred. Both 1 and 2 react with H2 to form hydrides, namely, the [(C 5Me5)2UH2]2/[(C 5Me5)2UH]2 equilibrium mixture and (C5Me5)2(hpp)UH, 3, respectively. Attempts to make a simple chloride derivative of 1 with Me3SiCl yielded a new tethered metallocene, (C5Me5)ClU(ν5-C 5Me4CH2SiMe2CH2-κC) , 4, which formally results from a silylmethyl C-H bond activation as well as insertion of the silyl group into the U-CH2 tuck-in linkage. The trivalent chloride [(C5Me5)2UCl]3, 5, is the byproduct of this reaction. This sequence of reactions is probably not initiated by the tuck-in functionality, since 2 does not react with Me 3SiCl under comparable conditions. Hydride complex 3 reacts readily with Me3SiCl to form (C5Me5) 2(hpp)UCl, but (C5Me5)2(hpp)UMe, 6, requires 100 °C to form the chloride. Complex 1 also displays complicated reactivity with HC=CPh, whereas 2 and 3 react with this substrate to form (C5Me5)2(hpp)U(C=CPh), 7, in high yield. Complex 1 converts PhSSPh cleanly to (C5Me5) 2U(SPh)2, 8, in a reaction that involves S-S cleavage and C-H bond formation. Complex 1 reacts with a 1:1 mixture of PhSSPh and p-tolylSS-p-tolyl to form a 1:2:1 mixture of (C5Me5) 2U(SPh)2, 8, (C5Me5) 2U(SPh)(S-p-tolyl), 9, and (C5Me5) 2U(S-p-tolyl)2, 10, but the mechanistic implications are compromised by exchange of 8 with 10 to make 9. PhSH, a possible intermediate in a δ-bond metathesis reaction pathway for the 1/PhSSPh reaction, reacts with 1 to form 8. Complex 2 forms a δ-bond metathesis product, (C 5Me4CH2SPh)(C5Me5)(hpp) U(SPh), 11, from PhSSPh that contains a new peralkylated cyclopentadienyl ligand. The reaction of 2 and PhSH forms (C5Me5) 2(hpp)U(SPh), 12. Complexes 1 and 2 react similarly with PhNH 2 to generate amide products (C5Me5) 2U(NHPh)2, 13, and (C5Me5) 2(hpp)U(NHPh), 14, respectively. No reactions were observed between complex 1 or 2 and methane, benzene, or toluene, but 1 and 2 react with CuI to form (C5Me5)2UI2, 15, and (C 5Me5)2(hpp)UI, 16, respectively, in which the CH2 tuck components have been converted to methyl groups.

Two-electron reductive reactivity of trivalent uranium tetraphenylborate complexes of (C5Me5)1- and (C5Me4H)1-

The reductive reactivity of the (BPh4)1- ligand in pentamethylcyclopentadienyl [(C5Me5)2U][(μ-η2:η1-Ph)2BPh2] (1) was compared with that of the tetramethyl analog, [(C5Me4H)2U][(μ-η6:η1-Ph)(μ-η1:η1-Ph)BPh2] (2) using PhSSPh as a probe to determine if the mode of (BPh4)1- bonding affected the reduction. Both complexes act as two-electron reductants to form (C5Me4R)2U(SPh)2 [R = Me, 3; H, 4], but only in the R = H case could the product be crystallographically characterized. An improved synthesis of 1 from [(C5Me5)2UH]2 (5) and [Et3NH][BPh4] is also reported as well as its reaction with MeCN that provides another route to the unusual, parallel-ring, uranium metallocene [(C5Me5)2U(NCMe)5][BPh4]2 (6).

Actinide hydride complexes as multielectron reductants: Analogous reduction chemistry from [(C5Me5)2UH]2, [(C5Me5)2UH2]2, and [(C5Me5)2ThH2]2

Methods to separate the components of the equilibrium mixture of [(C 5Me5)2UH]2 and [(C 5Me5)2-UH]2 have been developed that allow their reductive chemistry to be studied. These actinide hydrides can act as four-, six-, and eight-electron reductants depending on the substrate with H: as the byproduct of a H- → e- + 1/2 H2 redox couple. This hydride reduction chemistry allows complexes of redox-inactive Th4+ such as [(C5Me5) 2THH2]2 to be four- and six-electron reductants. [(C5Me5)2UH]2 and [(C5-Me5)2UH2]2 cleanly reduce 2 equiv of PhEEPh (E = S, Se) to form 2 equiv of (C5Me 5)2U(SPh)2 and (C5Me 5)2U(SePh)2 in an overall four-electron reduction in each case. [(C5Me5)2UH] 2 and [(C5Me5)2UH2] 2 also effect a six-electron reduction of 3 equiv of 1,3,5,7-cyclooctatetraene to [(C5Me5)(C8H 8)]2-(C8H8) and an eight-electron reduction of 2 equiv of PhN=NPh to form 2 equiv of the U6+ imido complex (C5Me5)2U(=NPh)2. In each reaction, H2 is a byproduct. This hydride-based reduction is also successful with the tetravalent thorium hydride [(C5Me 5)2THH2]2 which reduces 2 equiv of PhSSPh to (C5Me5)2-Th(SPh)2 and 3 equiv of C8H8 to [(C5Me5)(C 8H8)Th]2(C8H8) with concomitant formation of H2. X-ray crystallographic data are reported on [(C5Me5)2UH]2, [(C 5Me5)2UH2]2, and (C 5Me5)2U(SePh)2 as well as the thorium reduction products (C5Me5)2Th(SPh) 2 and [(C5Me5)(C8H 8)Th]2(C8H8).

Formation of (C5Me5)2U(EPh)Me, (C 5Me5)2U(EPh)2, and (C 5Me5)2U(η2-TeC6H 4) from (C5Me5)

(C5Me5)2UMe2, 1, reacts with 1 and 2 equiv of PhEEPh (E = S, Se) to form (C5Me5) 2UMe(EPh) (E = S, 2; Se, 3) and (C5Me5)2U(EPh) 2 (E = S, 4; Se,