Laurent Maron

Paul Sabatier University - Toulouse III | UPS Toulouse · Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes - FR 2568 - IRSAMC

Two‐electron oxidative addition is one of the most important elementary reactions for d‐block transition metals but it is uncommon for f‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic clu...

Two‐electron oxidative addition is one of the most important elementary reactions for d ‐block transition metals but it is uncommon for f ‐block elements. Here, we report the first examples of intermolecular oxidative addition of E−H (E=C, N) bonds to uranium(II) centers. The transient U(II) species was formed in‐situ by reducing a heterometallic c...

Polynuclear metal hydride clusters play important roles in various catalytic processes, with most of the reported polynuclear metal hydride clusters adopting a polyhedral three‐dimensional structure. Herein, we report the first example of a planar tetranuclear uranium hydride cluster [(CpCMe2CMe2Cp)U]4(μ2‐H)4(μ3‐H)4 (U4H8). It was synthesized by re...

Transition metal multimetallic complexes have seen intense study due to their unique bonding and potential for cooperative reactivity, but actinide–transition metal (An–TM) species are far less understood. We have synthesized uranium– and thorium–osmium heterometallic polyhydride complexes in order to study An–Os bonding and investigate the reactiv...

Cationic half‐sandwich zinc complexes containing chelating amines [Cp*Zn(Ln)][BAr4F] (2a, Cp* = η3‐C5Me5, Ln = N,N,N’,N’‐tetramethylethylenediamine, TMEDA; 2b, Ln = N,N,N’,N’‐tetraethylethylenediamine, TEEDA; 2c, Cp* = η1‐C5Me5, Ln = N,N,N′,N′′,N′′‐pentamethyl­diethylenetriamine, PMDTA; Ar4F = (3,5‐(CF3)2C6H3)4) reacted with dihydrogen (ca. 2 bar)...

Polynuclear metal hydride clusters play important roles in various catalytic processes, with most of the reported polynuclear metal hydride clusters adopting a polyhedral three‐dimensional structure. Herein, we report the first example of a planar tetranuclear uranium hydride cluster [(CpCMe2CMe2Cp)U]4(μ2‐H)4(μ3‐H)4 (U4H8). It was synthesized by re...

The stereodefined and highly substituted vinylsilanes are essential building blocks for constructing complex organic molecules. Transition metal‐mediated silylmetalation of alkynes was developed to overcome the limitations of conventional hydrosilylations; however, a very limited study was carried out to utilize transient vinylmetal species in cros...

The bulky β‐diketiminate ligand frameworks [BDIDCHP]⁻ and [BDIDipp/Ar]⁻ (BDI=[HC{C(Me)2N‐Dipp/Ar}2]⁻ (Dipp=2,6‐diisopropylphenyl (Dipp); Ar=2,6‐dicyclohexylphyenyl (DCHP) or 2,4,6‐tricyclohexylphyenyl (TCHP)) have been developed for the kinetic stabilisation of the first europium (II) hydride complexes, [(BDIDCHP)Eu(μ‐H)]2, [(BDIDipp/DCHP)Eu(μ‐H)]2...

End-on binding of dinitrogen to low valent metal centres is common in transition metal chemistry but remains extremely rare in f-elements chemistry. In particular, heterobimetallic end-on N2 bridged complexes of lanthanides are unprecedented despite their potential relevance in catalytic reduction of dinitrogen. Here we report the synthesis and cha...

Synthetic strategies to isolate molecular complexes of lanthanides, other than cerium, in the +4 oxidation state remain elusive, with only four complexes of Tb(iv) isolated so far. Herein, we present a new approach for the stabilization of Tb(iv) using a siloxide tripodal trianionic ligand, which allows the control of unwanted ligand rearrangements...

The stereodefined and highly substituted vinylsilanes are essential building blocks for constructing complex organic molecules. Transition metal‐mediated silylmetalation of alkynes was developed to overcome the limitations of conventional hydrosilylations; however, a very limited study was carried out to utilize transient vinylmetal species in cros...

A temperature-induced single-crystal to single-crystal transformation was observed in monoanionic N–P ligand-supported uranium azide complexes.

Coupling of octahedral, terminal d¹ molybdenum(v) nitrido complexes supported by a dianionic pentadentate ligand via N–N bond formation to give μ-dinitrogen complexes was found to be thermodynamically feasible but faces significant kinetic barriers. However, upon oxidation, a kinetically favored nucleophilic/electrophilic N–N bond forming mechanism...

Guanidinate homometallic rare-earth ethyl complexes [LLn(μ2-η¹:η²-Et)(Et)]2 (Ln = Y(1-Y), Lu(1-Lu)) and heterobimetallic rare-earth ethyl complexes LLn(Et)(μ2-η¹:η²-Et)(μ2-η¹-Et)(AlEt2) (Ln = Y(2-Y), Lu(2-Lu)) have been synthesized by the treatment of LLn(CH2C6H4NMe2-o)2 (L = (PhCH2)2NC(NC6H3ⁱPr2-2,6)2) with different equivalents of AlEt3 in toluen...

Reaction of the 1,2‐disilylenes {(DipArAm)Si}2 (DipArAm=[(NDip)2CAr]⁻, Dip=2,6‐diisopropylphenyl, Ar=4‐C6H4But (Ar’) 1 a or Ph 1 b) and two abnormal N‐heterocyclic silylenes, (DipArAm)SiOCSi{(NDip)2CAr} (Ar=Ar’ 3 a or Ph 3 b) with N2O led to formation of unprecedented examples of uncoordinated silicon analogues of carboxylic acid anhydrides, (DipAr...

The metal-substituted silylenes are of high interest, as the theoretical studies indicated that the silylenes with electropositive substituents have a small ΔES−T (singlet-triplet energy gap) or even the ground-state triplets. However, such compounds are highly unstable, and only two transient alkali metal-substituted silylenes M(tBu3Si)Si: (M = Li...

Reduction of the magnesium(II) diamide [Mg(TripNON)] (TripNON = 4,5-bis(2,4,6-triisopropylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) with 5% w/w K/KI leads to a good yield of a dianionic dimagnesium(I) species, as its potassium salt, [{K(TripNON)Mg}2]. An X-ray...

A straightforward and atom-economical route from P 4 to polyfunctional diphosphine ligands has been developed, revealing the versatile reactivity of the RPPR moiety.

Insertion of fluorenone into the lanthanum-phosporous bond of terminal phosphido complexes (PN)2La(PHR) (R = Mes (1a), R = Ph (1b) and R = tBu (1c)) results in the formation of...

The high stability of the + IVoxidation state limits thorium redox reactivity. Here we report the synthesis and the redox reactivity of two Th(IV) complexes supported by the arene‐tethered tris(siloxide) tripodal ligands [(KOSiR2Ar)3‐arene)]. The two‐electron reduction of these Th(IV) complexes generates the doubly reduced [KTh((OSi(OtBu)2Ar)3‐aren...

The high stability of the +4 oxidation state limits thorium redox reactivity. Here we report the synthesis and the redox reactivity of two Th(IV) complexes supported by the arene‐tethered tris(siloxide) tripodal ligands [(KOSiR2Ar)3‐arene)]. The two electron reduction of these Th(IV) complexes generates the doubly reduced [KTh((OSi(OtBu)2Ar)3‐arene...

Reaction of the 1,2-disilylenes {(DipArAm)Si}2 (DipArAm = [(NDip)2CAr]-, Dip = 2,6-diisopropylphenyl, Ar = 4-C6H4But (Ar’) 1a or Ph 1b) and two abnormal N-heterocyclic silylenes, (DipArAm)SiOCSi{(NDip)2CAr} (Ar = Ar’ 3a or Ph 3b) with N2O led to formation of unprecedented examples of uncoordinated silicon analogues of carboxylic acid anhydrides, (D...

Reduction of the magnesium(II) diamide [Mg(TripNON)] (TripNON = 4,5-bis(2,4,6-triisopropylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) with 5% w/w K/KI leads to a good yield of a dianionic dimagnesium(I) species, as its potassium salt, [{K(TripNON)Mg}2]. An X-ray crystallographic analysis shows the molecule to contain a very long Mg‒Mg bond (3.137(2...

Uranium diazomethanediide complexes can be prepared and their synthesis, structure and reactivity were explored. Reaction of the uranium imido compound [η⁵‐1,2,4‐(Me3Si)3C5H2]2U=N(p‐tolyl)(dmap) (1) or [η⁵‐1,3‐(Me3C)2C5H3]2U=N(p‐tolyl)(dmap) (4) with Me3SiCHN2 cleanly yields the first isocyanoimido metal complexes [η⁵‐1,2,4‐(Me3Si)3C5H2]2U(=NNC)(μ‐...

Understanding the role of multimetallic cooperativity and of alkali ion-binding in the second coordination sphere is important for the design of complexes that can promote dinitrogen (N2) cleavage and functionalization. Herein, we compare the reaction products and mechanism of N2 reduction of the previously reported K2-bound dinuclear uranium(iii)...

Uranium diazomethanediide complexes readily can be prepared and their synthesis, structure and reactivity were explored. Reaction of the uranium imido compound [η5‐1,2,4‐(Me3Si)3C5H2]2U=N(p‐tolyl)(dmap) (1) or [η5‐1,3‐(Me3C)2C5H3]2U=N(p‐tolyl)(dmap) (4) with Me3SiCHN2 cleanly yields the first isocyanoimido metal complexes [η5‐1,2,4‐(Me3Si)3C5H2]2U(...

Benzene reduction by molecular complexes remain a significant synthetic challenge, requiring harsh reaction conditions involving group 1 metals. Even under such forcing conditions only the one- or two-electron reduction of benzene has been achieved. The high stability of benzene is attributed to its aromaticity, imparted by the delocalisation of el...

The dimeric β‐diketiminato calcium hydride, [(DippBDI)CaH]2 (DippBDI = HC{(Me)CN‐2,6‐i‐Pr2C6H3}2), reacts with ortho‐, meta‐ or para‐tolyl mercuric compounds to afford hydridoarylcalcium compounds, [(DippBDI)2Ca2(μ‐H)(μ‐o‐,m‐,p‐tolyl)], in which dimer propagation occurs either via μ2‐η¹‐η¹ or μ2‐η¹‐η⁶ bridging between the calcium centers. In each c...

Transition-metal-catalyzed cross-coupling of propargylic electrophiles and Grignard reagents provides densely functionalized products that are extremely useful synthetic intermediates. However, examples of conversion of propargylic derivatives to form propargyl compounds remain limited due to the challenging regioselectivity. We use LaCl3·2LiCl to...

Simple lanthanide cyclopentadienyl (Cp) complexes can photochemically cleave the sp3 carbon-chlorine bond of unactivated chlorinated hydrocarbons including polyvinyl chloride (PVC). The excited state lifetimes of these simple complexes are among the longest observed for cerium complexes (175 ns for [(CpMe4)2Ce(μ-Cl)]2) and the light absorption by t...

In the presence of TMEDA (TMEDA=N,N,N’,N’‐tetramethylethylenediamine), zinc dihydride reacted with germanium(II) compounds (BDI−H)Ge (1) and [(BDI)Ge][B(3,5‐(CF3)2C6H3)4] (3) (BDI‐H = HC{(C=CH2)(CMe)(NAr)2}, BDI = [HC(CMeNAr)2]; Ar = 2,6‐ⁱPr2C6H3) by formal insertion of the germanium(II) center into the Zn−H bond of polymeric [ZnH2]n to give neutra...

The activation of dinitrogen (N2) by transition metals is central to the highly energy intensive, heterogeneous Haber–Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N2 with d‐ and f‐block metals, though little success has been had with main group metals. Here we report that the reduction of a...

A guanidinato-stabilized binuclear yttrium carbyne complex [(PhCH2)2NC(NC6H3ⁱPr2-2,6)2]2Y2(μ2-Me)(AlMe3)2(μ4-CH) (1) was synthesized via C–H bond activation and its versatile reactivities were investigated. Complex 1 underwent σ-bond metathesis with PhSSPh and nucleophilic addition with PhCN to form the corresponding yttrium thiolate complex 3 and...

The first examples of regioselective aryl ortho-C-H functionalization with diphenyldiazomethane for the construction of Caryl-Nhydrazinato bonds were accomplished via the activation of C-H bonds and the subsequent reaction of diphenyldiazomethane with the RE-Caryl bond. The reactions of rare-earth metal monoalkyl complexes LRE(CH2SiMe3)(THF)2 (L =...

The activation of dinitrogen (N 2 ) by transition metals is central to the highly energy intensive, heterogeneous Haber–Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N 2 with d‐ and f‐block metals, though little success has been had with main group metals. Here we report that the reduction of...

The synthesis of molecular uranium complexes in oxidation states lower than +3 remains a challenge despite the interest for their multielectron transfer reactivity and electronic structures. Herein, we report the one- and two-electron reduction of a U(III) complex supported by an arene-tethered tris(siloxide) tripodal ligand leading to the mono-red...

This work reports the synthesis, characterization, and reactivity of the first example of a well‐defined zinc α‐diazoalkyl complex. Treatment of zinc(I)‐zinc(I) bonded compound L2Zn2 [L=CH3C(2,6‐ⁱPr2C6H3N)CHC(CH3)(NCH2CH2PPh2)] or zinc(II) hydride LZnH with trimethylsilyldiazomethane affords zinc diazoalkyl complex LZnC(N2)SiMe3. This complex liber...

The synthesis, characterization, and solid-state structure of bulky alkoxy- and aryloxy-supported yttrium polynuclear hydrides are reported. Hydrogenolysis of the supertrityl alkoxy anchored yttrium dialkyl, Y(OTr*)(CH2SiMe3)2(THF)2 (1) (Tr* = tris(3,5-di-tert-butylphenyl)methyl), resulted in the clean conversion to the tetranuclear dihydride, [Y(O...

17O-labelled tungsten siloxide complexes [WOCl2(OSitBu3)2] (1-Cl) and [WOMe2(OSitBu3)2] (1-Me) were prepared and characterized by 17O MAS NMR, with input from theoretical calculations of NMR parameters. Guidelines linking 17O NMR parameters and the coordination sphere of molecular and silica-grafted tungsten oxo species are proposed. The grafting o...

Simple lanthanide cyclopentadienyl (Cp) complexes can photochemically cleave the sp3 carbon-chlorine bond of unactivated chlorinated hydrocarbons including polyvinyl chloride (PVC). The excited state lifetimes of these simple complexes are long (175 ns for (CpMe4)2CeCl) and the light absorption by the Cp ligand is efficient, so photocatalytic react...

This work reports the synthesis, characterization, and reactivity of the first example of a well‐defined zinc α‐diazoalkyl complex. Treatment of zinc(I)‐zinc(I) bonded compound L 2 Zn 2 [ L =CH 3 C(2,6‐ ⁱ Pr 2 C 6 H 3 N)CHC(CH 3 )(NCH 2 CH 2 PPh 2 )] or zinc(II) hydride L ZnH with trimethylsilyldiazomethane affords zinc diazoalkyl complex L ZnC(N 2...

Lewis acidic bismuth compounds have found catalytic applications in the reduction of unsaturated bonds. In this work, we present the inferences from the mechanistic studies on the catalytic reduction of ketones and phosphine oxides using the organobismuth dication [NMe2C6H4Bi(L)3][Al{OC(CF3)3}4]2 in the presence of silanes as reducing agents. Exper...

Reduction of a range of amido‐ and aryloxy‐aluminum dihydride complexes, e.g. [AlH2(NR3){N(SiMe3)2}] (NR3=NMe3 or N‐methylpiperidine (NMP)), with β‐diketiminato dimagnesium(I) reagents, [{(ArNacnac)Mg}2] (ArNacnac=[HC(MeCNAr)2]⁻, Ar=mesityl (Mes) or 2,6‐xylyl (Xyl)), have afforded deep red mixed valence aluminum hydride cluster compounds, [Al6H8(NR...

A series of new Me2Si-bridged cyclopentadiene/indene proligands {Me2Si(R2',5'2-R3',4'2-Cp)(R2,R4,R5,R6-Ind)H2} (1a-j) with various substitutions both on the indene and cyclopentadiene moieties was prepared. The corresponding C1-symmetric group 4 ansa-metallocene complexes (M = Zr, Hf), namely, {Me2Si(Me4Cp)(Ind)}ZrCl2 (2a-Zr), {Me2Si(Me4Cp)(2-Me,4-...

Reduction of a range of amido‐ and aryloxy‐aluminum dihydride complexes, e.g. [AlH 2 (NR 3 ){N(SiMe 3 ) 2 }] (NR 3 =NMe 3 or N‐methylpiperidine (NMP)), with β‐diketiminato dimagnesium(I) reagents, [{( Ar Nacnac)Mg} 2 ] ( Ar Nacnac=[HC(MeCNAr) 2 ] ⁻ , Ar=mesityl (Mes) or 2,6‐xylyl (Xyl)), have afforded deep red mixed valence aluminum hydride cluster...

The activation of dinitrogen (N2) by transition metals is central to the highly energy intensive, heterogenous Haber-Bosch process. Considerable progress has been made towards more sustainable homogeneous activations of N2 with d- and f-block metals, though little success has been had with main group metals. Here we report that the reduction of a b...

The chemistry of lanthanides is limited to one electron transfer reactions due to the difficulty of accessing multiple oxidation states. Here we report that a redox-active ligand combining three siloxides with an arene ring in a tripodal ligand can stabilize cerium complexes in four different redox states and can promote multielectron redox reactiv...

Herein, we report the redox reactivity of a multimetallic uranium complex supported by triphenylsiloxide (−OSiPh3) ligands, where we show that low valent synthons can be stabilized via an unprecedented mechanism involving intramolecular ligand migration. The two‐ and three‐electron reduction of the oxo‐bridged diuranium(IV) complex [{(Ph3SiO)3(DME)...

In the field of metal-mediated selective and easier organic reactions, the present chapter focuses on the activation of at least one main step in the cleft of a dinuclear platform, in which a 1e-1e process occurs. This contribution emphasizes on the concepts that govern the conception of the coordination sphere in order to maintain the two metal ce...

Reactions of a dimagnesium(i) compound, [{(DipNacnac)Mg}2] (DipNacnac = [HC(MeCNDip)2]-, Dip = 2,6-diisopropylphenyl), pre-activated by coordination with simple Lewis bases (4-dimethylaminopyridine, DMAP; or TMC, :C(MeNCMe)2), with 1 atmosphere of CO in the presence of one equivalent of Mo(CO)6 at room temperature, led to the reductive tetramerisat...

The metal-mediated propargylation or allenylation of carbonyl compounds is well-adapted to the preparation of homopropargylic or allenylic alcohols, which are multifunctional intermediates in synthetic chemistry. However, the regioselectivity of reactions using propargyl or allenyl metal reagents is difficult to control, owing to the equilibrium be...

Reduction of a range of amido- and aryloxy-aluminum dihydride complexes, e.g. [AlH2(NR3){N(SiMe3)2}] (NR3 = NMe3 or N-methylpiperidine (NMP)), with -diketiminato dimagnesium(I) reagents, [{(ArNacnac)Mg}2] (ArNacnac = [HC(MeCNAr)2]-, Ar = mesityl (Mes) or 2,6-xylyl (Xyl)), have afforded deep red mixed valence aluminum hydride cluster compounds, [Al6...

Reduction of a range of amido- and aryloxy-aluminum dihydride complexes, e.g. [AlH2(NR3){N(SiMe3)2}] (NR3 = NMe3 or N-methylpiperidine (NMP)), with -diketiminato dimagnesium(I) reagents, [{(ArNacnac)Mg}2] (ArNacnac = [HC(MeCNAr)2]-, Ar = mesityl (Mes) or 2,6-xylyl (Xyl)), have afforded deep red mixed valence aluminum hydride cluster compounds, [Al6...

Although examples of multiple bonds between actinide elements and main‐group elements are quite common, studies of the multiple bonds between actinide elements and transition metals are extremely rare owing to difficulties associated with their synthesis. Here we report the first example of molecular uranium complexes featuring a cis‐[M →→ ${{\rm{...

Although examples of multiple bonds between actinide elements and main‐group elements are quite common, studies of the multiple bonds between actinide elements and transition metals are extremely rare owing to difficulties associated with their synthesis. Here we report the first example of molecular uranium complexes featuring a cis ‐[M U M] core...

Herein, we report the redox reactivity of a multimetallic uranium complex supported by triphenylsiloxide (−OSiPh 3 ) ligands, where we show that low valent synthons can be stabilized via an unprecedented mechanism involving intramolecular ligand migration. The two‐ and three‐electron reduction of the oxo‐bridged diuranium(IV) complex [{(Ph 3 SiO) 3...

Reactions of a dimagnesium(I) compound, [{(DipNacnac)Mg}2] (DipNacnac = [HC(MeCNDip)2]-, Dip = 2,6-diisopropylphenyl), pre-activated by coordination with simple Lewis bases (4-dimethylaminopyridine, DMAP; or TMC, :C(MeNCMe)2), with 1 atmosphere of CO in the presence of one equivalent of Mo(CO)6 at room temperature, led to the reductive tetramerisat...

Correction for ‘Isolation of C1 through C4 derivatives from CO using heteroleptic uranium( iii ) metallocene aryloxide complexes’ by Robert J. Ward et al. , Chem. Sci. , 2023, 14 , 2024–2032, https://doi.org/10.1039/D2SC06375A.

The conversion of C1 feedstock molecules such as CO into commodity chemicals is a desirable, but challenging, endeavour. When the U(iii) complex, [(C5Me5)2U(O-2,6- t Bu2-4-MeC6H2)], is exposed to 1 atm of CO, only coordination is observed by IR spectroscopy as well as X-ray crystallography, unveiling a rare structurally characterized f element carb...

Thorium redox chemistry is extremely scarce due to the high stability of ThIV. Here we report two unique examples of thorium arenide complexes prepared by reduction of a ThIV‐siloxide complex in presence of naphthalene, the mononuclear arenide complex [K(OSi(OtBu)3)3Th(η⁶‐C10H8)] (1) and the inverse‐sandwich complex [K(OSi(OtBu)3)3Th]2(μ‐η⁶,η⁶‐C10H...

Thorium redox chemistry is extremely scarce due to the high stability of Th(IV). Here we report two unique examples of thorium arenide complexes prepared by reduction of a Th(IV)‐siloxide complex in presence of naphthalene, the mononuclear arenide complex [K(OSi(OtBu)3)3Th(η6‐C10H8)] (1) and the inverse‐sandwich complex [K(OSi(OtBu)3)3Th]2(μ‐η6,η6‐...

Herein we report the first catalytic decarbonylation and decarbonylative hydroamination of formamides without using additives enabled by a redox-neutral rare earth catalyst. The protocol displays complete N-aryl/alkenyl formamide-selectivity, thus providing a wide variety of creative uses of the N-formylation and N-deformylation method and opening...

Reaction of the potassium pentamethylcyclopentadienyl iridate tris-hydride K[IrCp*H3] with UCl4 and ThCl4(DME)2 led to the complete replacement of the halide ligands to generate multimetallic complexes U{(μ-H)3IrCp*}4 (1) and Th{[(μ-H2)(H)IrCp*]2[(μ-H)3IrCp*]2} (2), respectively. These analogues feature a significant discrepancy in hydride bonding...

[This corrects the article DOI: 10.1021/jacsau.2c00251.].

Cyclobutadienyl complexes of the f-elements are a relatively new yet poorly understood class of sandwich and half-sandwich organometallic compounds. We now describe cyclobutadienyl transfer reactions of the magnesium reagent [(η4-Cb'''')Mg(THF)3] (1), where Cb'''' is tetrakis(trimethylsilyl)cyclobutadienyl, toward thorium(IV) and uranium(IV) tetrac...

The tetrapyralzolylpyridyl diborate pentadentate ligand B2Pz4Py has been complexed to Ti(III) to form the chloro complex (B2Pz4Py)Ti(III)Cl, which is a convenient starting material for preparing alkyl and hydride derivatives of this ligand. The former (R = CH3 and CH2SiMe3) are highly thermally stable and do not react with dihydrogen to form (B2Pz4...

The uranyl complex UVIO2Cl(LMes) of the redox-active, acyclic dipyrrin-diimine anion LMes- [HLMes = 1,9-di-tert-butyl-imine-5-(mesityl)dipyrrin] is reported, and its redox property is explored and compared with that of the previously reported UVIO2Cl(LF) [HLF = 1,9-di-tert-butyl-imine-5-(pentafluorophenyl)dipyrrin] to understand the influence of th...

Herein we report the first example of a mononuclear uranium complex, [U4+(NP(pip)3)4] (1-U), that selectively reduces dioxygen to produce a terminal oxo complex, [U6+O(NP(pip)3)4] (2-U; [NP(pip)3]1– is tris(piperidinyl)imidophosphorane). Reactions between...

In this contribution, we illustrate uranium complexes bearing a pendant borate (i.e. 1 and 2) or a pendant borane (i.e. 3 and 4) moiety via reaction of the highly strained uranacycle I with various 3‐coordinate boranes. Complexes 3 and 4 represent the first examples of uranium complexes with a pendant borane Lewis acid. Moreover, complex 3 was capa...

The controlled functionalization of a single fluorine in a CF3 group is difficult and rare. Photochemical C-F bond functionalization of the sp3-C-H bond in trifluorotoluene, PhCF3, is achieved using catalysts made from earth-abundant lanthanides, (CpMe4)2Ln(2-O-3,5- t Bu2-C6H2)(1-C{N(CH)2N(iPr)}) (Ln = La, Ce, Nd and Sm, CpMe4 = C5Me4H). The Ce com...

Ligands play a key role in controlling activity of organometallic complexes so that development of new ligands to overcome the challenge is the main topic of modern chemistry. The first example of 1,1-hydride migratory insertion and intramolecular redox reaction has been realized in this work by applying a new ligand in rare-earth metal chemistry....

An extremely bulky xanthene bridged diamide ligand (TCHPNON = 4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) has been developed and used to prepare two monomeric diamido-calcium complexes [(TCHPNON)Ca(D)n] (D = THF, n = 2, 3; D = toluene, n = 1, 4). Reduction of 4 with 5% w/w K/KI under an N2 atmosphere gave the first well-d...

In this contribution, we illustrate uranium complexes bearing a pendant borate ( i.e. 1 and 2 ) or a pendant borane ( i.e. 3 and 4 ) moiety via reaction of the highly strained uranacycle I with various 3‐coordinate boranes. Complexes 3 and 4 represent the first examples of uranium complexes with a pendant borane Lewis acid. Moreover, complex 3 was...

An extremely bulky xanthene bridged diamide ligand (TCHPNON = 4,5-bis(2,4,6-tricyclohexylanilido)-2,7-diethyl-9,9-dimethyl-xanthene) has been developed and used to prepare two monomeric diamido-calcium complexes [(TCHPNON)Ca(D)n] (D = THF, n = 2, 3; D = toluene, n = 1, 4). Reduction of 4 with 5% w/w K/KI under an N2 atmosphere gave the first well-d...

Radical-bridged diuranium complexes are desirable for their potential high exchange coupling and single molecule magnet (SMM) behavior, but remain rare. Here we report for the first time radical-bridged diuranium(iv) and diuranium(iii) complexes. Reaction of [U{N(SiMe3)2}3] with 2,2'-bipyrimidine (bpym) resulted in the formation of the bpym-bridged...

The nature of transition-metal-olefin bonding has been explained by the Dewar-Chatt-Duncanson model within a continuum of two extremes, namely, a π-complex and a metallacyclopropane. The textbook rule suggests that a low-spin late-transition-metal-ethylene complex more likely forms a π-complex rather than a metallacyclopropane. Herein, we report a...