The reaction of monomeric [(TptBu,Me)LuMe2] (TptBu,Me=tris(3‐Me‐5‐tBu‐pyrazolyl)borate) with primary aliphatic amines H2NR (R=tBu, Ad=adamantyl) led to lutetium methyl primary amide complexes [(TptBu,Me)LuMe(NHR)], the solid‐state structures of which were determined by XRD analyses. The mixed methyl/tetramethylaluminate compounds [(TptBu,Me)LnMe({μ2‐Me}AlMe3)] (Ln=Y, Ho) reacted selectively and in high yield with H2NR, according to methane elimination, to afford heterobimetallic complexes: [(TptBu,Me)Ln({μ2‐Me}AlMe2)(μ2‐NR)] (Ln=Y, Ho). X‐ray structure analyses revealed that the monomeric alkylaluminum‐supported imide complexes were isostructural, featuring bridging methyl and imido ligands. Deeper insight into the fluxional behavior in solution was gained by 1H and 13C NMR spectroscopic studies at variable temperatures and 1H–89Y HSQC NMR spectroscopy. Treatment of [(TptBu,Me)LnMe(AlMe4)] with H2NtBu gave dimethyl compounds [(TptBu,Me)LnMe2] as minor side products for the mid‐sized metals yttrium and holmium and in high yield for the smaller lutetium. Preparative‐scale amounts of complexes [(TptBu,Me)LnMe2] (Ln=Y, Ho, Lu) were made accessible through aluminate cleavage of [(TptBu,Me)LnMe(AlMe4)] with N,N,N′,N′‐tetramethylethylenediamine (tmeda). The solid‐state structures of [(TptBu,Me)HoMe(AlMe4)] and [(TptBu,Me)HoMe2] were analyzed by XRD. 相似文献
Novel silylation reactions at [Ge9] Zintl clusters starting from the chlorosilanes SiR3Cl (R = iBu, iPr, Et) and the Zintl phase K4Ge9 are reported. The formation of the tris‐silylated anions [Ge9(SiR3)3]– [R = iBu ( 1a ), iPr ( 1b ), Et ( 1c )] by heterogeneous reactions in acetonitrile was monitored by ESI‐MS measurements. For R = iBu 1H, 13C and 29Si NMR experiments confirmed the exclusive formation of 1a . Subsequent reactions of 1a with CuNHCDippCl and Au(PPh3)Cl result in formation of the neutral metal complex (CuNHCDipp)[Ge9{Si(iBu)3}3]·0.5 tol ( 2 ·0.5 tol) and the metal bridged dimeric unit {Au[Ge9{Si(iBu)3}3]2}– ( 3a ), isolated as a (K‐18c6)+ salt in (K‐18c6)Au[Ge9{Si(iBu)3}3]2·tol ( 3 ·tol), respectively. Finally, from a toluene/hexane solution of 1a in presence of 18‐crown‐6, crystals of the compound (K‐18c6)2[Ge9{Si(iBu)3}2]·tol ( 4 ·tol), containing the bis‐silylated cluster anion [Ge9(Si(iBu)3)2]2– ( 4a ), were obtained. The compounds 2 ·0.5 tol, 3 ·tol and 4 ·tol were characterized by single‐crystal structure determination. 相似文献
Investigations on the Reactivity of [Me2AlP(SiMe3)2]2 with Base‐stabilized Organogalliumhalides and ‐hydrides [Me2AlP(SiMe3)2]2 ( 1 ) reacts with dmap?Ga(Cl)Me2, dmap?Ga(Me)Cl2, dmap?GaCl3 and dmap?Ga(H)Me2 with Al‐P bond cleavage and subsequent formation of heterocyclic [Me2GaP(SiMe3)2]2 ( 2 ) as well as dmap?AlMexCl3?x (x = 3 8 ; 2 3 ; 1 4 ; 0 5 ). The reaction between equimolar amounts of dmap?Al(Me2)P(SiMe3)2 and dmap?Ga(t‐Bu2)Cl yield dmap?Ga(t‐Bu2)P(SiMe3)2 ( 6 ) and dmap?AlMe2Cl ( 3 ). 2 – 8 were characterized by NMR spectroscopy, 2 and 6 also by single crystal X‐ray diffraction. 相似文献
Deprotonation of aminophosphaalkenes (RMe2Si)2C?PN(H)(R′) (R=Me, iPr; R′=tBu, 1‐adamantyl (1‐Ada), 2,4,6‐tBu3C6H2 (Mes*)) followed by reactions of the corresponding Li salts Li[(RMe2Si)2C?P(M)(R′)] with one equivalent of the corresponding P‐chlorophosphaalkenes (RMe2Si)2C?PCl provides bisphosphaalkenes (2,4‐diphospha‐3‐azapentadienes) [(RMe2Si)2C?P]2NR′. The thermally unstable tert‐butyliminobisphosphaalkene [(Me3Si)2C?P]2NtBu ( 4 a ) undergoes isomerisation reactions by Me3Si‐group migration that lead to mixtures of four‐membered heterocyles, but in the presence of an excess amount of (Me3Si)2C?PCl, 4 a furnishes an azatriphosphabicyclohexene C3(SiMe3)5P3NtBu ( 5 ) that gave red single crystals. Compound 5 contains a diphosphirane ring condensed with an azatriphospholene system that exhibits an endocylic P?C double bond and an exocyclic ylidic P(+)? C(?)(SiMe3)2 unit. Using the bulkier iPrMe2Si substituents at three‐coordinated carbon leads to slightly enhanced thermal stability of 2,4‐diphospha‐3‐azapentadienes [(iPrMe2Si)2C?P]2NR′ (R′=tBu: 4 b ; R′=1‐Ada: 8 ). According to a low‐temperature crystal‐structure determination, 8 adopts a non‐planar structure with two distinctly differently oriented P?C sites, but 31P NMR spectra in solution exhibit singlet signals. 31P NMR spectra also reveal that bulky Mes* groups (Mes*=2,4,6‐tBu3C6H2) at the central imino function lead to mixtures of symmetric and unsymmetric rotamers, thus implying hindered rotation around the P? N bonds in persistent compounds [(RMe2Si)2C?P]2NMes* ( 11 a , 11 b ). DFT calculations for the parent molecule [(H3Si)2C?P]2NCH3 suggest that the non‐planar distortion of compound 8 will have steric grounds. 相似文献
The reactivity towards AlMe3 of discrete cationic ansa‐zirconocenes 2 a,b that are ubiquitously used in isoselective propylene polymerization and based on [{Ph(H)C(3,6‐tBu2‐Flu)(3‐tBu‐5‐Et‐Cp)}ZrMe2)] {Cp‐Flu} and rac‐[{Me2Si‐(2‐Me‐4‐Ph‐Ind)2}ZrMe2] {SBI} was scrutinized. The first example of a structurally characterized Group 4 metallocene AlMe3 adduct ( 3 b ) is reported. In the presence of excess AlMe3, the {SBI}‐based AlMe3 adduct 3 b undergoes a slow decomposition via C? H activation in a bridging methyl unit to yield a new species ( 4 b ) with a trimetallic {Zr(μ‐CH2)(μ‐Me)AlMe(μ‐Me)AlMe2} core. EXSY NMR data for the process 2 b ? 3 b → 4 b suggest very rapid and reversible binding of an additional AlMe3 molecule onto AlMe3 adduct 3 b . The resulting heterotrimetallic species intermediates exchange of methyl groups between different metal centers and slowly undergoes the C? H activation reaction towards 4 b . 相似文献
Upon reacting SeCl4 with Me3Si–F–Al(ORF)3, the selenonium salt SeMeCl2[al‐f‐al] ( 1 ) {[al‐f‐al]– = [F[Al(OC(CF3)3)3]2]–} was obtained and characterized by NMR, IR, and Raman spectroscopy as well as single crystal XRD experiments. Despite the [SeX3]+ (X = F, Cl, Br, I) and [SeR3]+ salts (R = aliphatic organic residue) being well known and thoroughly studied, the mixed cations are scarce. The only previous example of a salt with the [SeMeCl2]+ cation is SeMeCl2[SbCl6], which was never structurally characterized and is unstable in solution over hours. Only 1H‐NMR studies and IR spectra of this compound are known. The unexpected use of Me3Si–F–Al(ORF)3 as a methylating agent was investigated via DFT calculations and NMR experiments of the reaction solution. The reaction of SeCl3[al‐f‐al] with Me3Si‐Cl at room temperature in CH2Cl2 proved to yield the same product with Me3Si–Cl acting as a methylating agent. 相似文献
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XXII. The Formation of [η2‐{tBu–P=P–SiMe3}Pt(PR3)2] from (Me3Si)tBuP–P=P(Me)tBu2 and [η2‐{C2H4}Pt(PR3)2] (Me3Si)tBuP–P = P(Me)tBu2 reacts with [η2‐{C2H4}Pt(PR3)2] yielding [η2‐{tBu–P=P–SiMe3}Pt(PR3)2]. However, there is no indication for an isomer which would be the analogue to the well known [η2‐{tBu2P–P}Pt(PPh3)2]. The syntheses and NMR data of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] and [η2‐{tBu–P=P–SiMe3}Pt(PMe3)2] as well as the results of the single crystal structure determination of [η2‐{tBu–P=P–SiMe3}Pt(PPh3)2] are reported. 相似文献
Lithium 8‐amidoquinoline ( 1 ) and lithium 8‐(trialkylsilylamido)quinoline [SiMe2tBu ( 2 ), SiiPr3 ( 3 )] react with dimethylgallium chloride to the metathesis products dimethylgallium 8‐amidoquinoline ( 4 ) as well as dimethylgallium 8‐(trialkylsilylamido)quinoline [SiMe2tBu ( 5 ), SiiPr3 ( 6 )]. The gallium atoms are in distorted tetrahedral environments. During the synthesis of 5 , orange dimethylgallium 2‐butyl‐8‐(tert‐butyldimethylsilylamido)quinoline ( 7 ) was found as by‐product. The metathesis reactions of Me2GaCl with LiN(R)CH2Py (Py = 2‐pyridyl) yield the corresponding 2‐pyridylmethylamides Me2Ga‐N(H)CH2Py ( 8 ), Me2Ga‐N(SiMe2tBu)CH2Py ( 9 ) and Me2Ga‐N(SiiPr3)CH2Py ( 10 ). In these complexes the gallium atoms show a distorted tetrahedral coordination sphere. However, derivative 8 crystallizes dimeric with bridging amido units whereas in 9 and 10 the 2‐pyridylmethylamido moieties act as bidentate ligands leading to monomeric molecules. 相似文献
Synthesis and Characterization of New Intramolecularly Nitrogen‐stabilized Organoaluminium‐ and Organogallium Alkoxides The intramolecularly nitrogen stabilized organoaluminium alkoxides [Me2Al{μ‐O(CH2)3NMe2}]2 ( 1a ), Me2AlOC6H2(CH2NMe2)3‐2,4,6 ( 2a ), [(S)‐Me2Al{μ‐OCH2CH(i‐Pr)NH‐i‐Pr}]2 ( 3a ) and [(S)‐Me2Al{μ‐OCH2CH(i‐Pr)NHCH2Ph}]2 ( 4 ) are formed by reacting equimolar amounts of AlMe3 and Me2N(CH2)3OH, C6H2[(CH2NMe2)3‐2,4,6]OH, (S)‐i‐PrNHCH(i‐Pr)CH2OH, or (S)‐PhCH2NHCH(i‐Pr)CH2OH, respectively. An excess of AlMe3 reacts with Me2N(CH2)2OH, Me2N(CH2)3OH, C6H2[(CH2NMe2)3‐2,4,6]OH, and (S)‐i‐PrNHCH(i‐Pr)CH2OH producing the “pick‐a‐back” complexes [Me2AlO(CH2)2NMe2](AlMe3) ( 5 ), [Me2AlO(CH2)3NMe2](AlMe3) ( 1b ), [Me2AlOC6H2(CH2NMe2)3‐2,4,6](AlMe3)2 ( 2b ), and [(S)‐Me2AlOCH2CH(i‐Pr)NH‐i‐Pr](AlMe3) ( 3b ), respectively. The mixed alkyl‐ or alkenylchloroaluminium alkoxides [Me(Cl)Al{μ‐O(CH2)2NMe2}]2 ( 6 ) and [{CH2=C(CH3)}(Cl)Al{μ‐O(CH2)2NMe2}]2 ( 8 ) are to obtain from Me2AlCl and Me2N(CH2)2OH and from [Cl2Al{μ‐O(CH2)2NMe2}]2 ( 7 ) and CH2=C(CH3)MgBr, respectively. The analogous dimethylgallium alkoxides [Me2Ga{μ‐O(CH2)3NMe2}]2 ( 9 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)NH‐i‐Pr}]n ( 10 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)NHCH2Ph}]n ( 11 ), [(S)‐Me2Ga{μ‐OCH2CH(i‐Pr)N(Me)CH2Ph}]n ( 12 ) and [(S)‐Me2Ga{μ‐OCH2(C4H7NHCH2Ph)}]n ( 13 ) result from the equimolar reactions of GaMe3 with the corresponding alcohols. The new compounds were characterized by elemental analyses, 1H‐, 13C‐ and 27Al‐NMR spectroscopy, and mass spectrometry. Additionally, the structures of 1a , 1b , 2a , 2b , 3a , 5 , 6 and 8 were determined by single crystal X‐ray diffraction. 相似文献
Diimido, Imido Oxo, Dioxo, and Imido Alkylidene Halfsandwich Compounds via Selective Hydrolysis and α—H Abstraction in Molybdenum(VI) and Tungsten(VI) Organyl Complexes Organometal imides [(η5‐C5R5)M(NR′)2Ph] (M = Mo, W, R = H, Me, R′ = Mes, tBu) 4 — 8 can be prepared by reaction of halfsandwich complexes [(η5‐C5R5)M(NR′)2Cl] with phenyl lithium in good yields. Starting from phenyl complexes 4 — 8 as well as from previously described methyl compounds [(η5‐C5Me5)M(NtBu)2Me] (M = Mo, W), reactions with aqueous HCl lead to imido(oxo) methyl and phenyl complexes [(η5‐C5Me5)M(NtBu)(O)(R)] M = Mo, R = Me ( 9 ), Ph ( 10 ); M = W, R = Ph ( 11 ) and dioxo complexes [(η5‐C5Me5)M(O)2(CH3)] M = Mo ( 12 ), M = W ( 13 ). Hydrolysis of organometal imides with conservation of M‐C σ and π bonds is in fact an attractive synthetic alternative for the synthesis of organometal oxides with respect to known strategies based on the oxidative decarbonylation of low valent alkyl CO and NO complexes. In a similar manner, protolysis of [(η5‐C5H5)W(NtBu)2(CH3)] and [(η5‐C5Me5)Mo(NtBu)2(CH3)] by HCl gas leads to [(η5‐C5H5)W(NtBu)Cl2(CH3)] 14 und [(η5‐C5Me5)Mo(NtBu)Cl2(CH3)] 15 with conservation of the M‐C bonds. The inert character of the relatively non‐polar M‐C σ bonds with respect to protolysis offers a strategy for the synthesis of methyl chloro complexes not accessible by partial methylation of [(η5‐C5R5)M(NR′)Cl3] with MeLi. As pure substances only trimethyl compounds [(η5‐C5R5)M(NtBu)(CH3)3] 16 ‐ 18 , M = Mo, W, R = H, Me, are isolated. Imido(benzylidene) complexes [(η5‐C5Me5)M(NtBu)(CHPh)(CH2Ph)] M = Mo ( 19 ), W ( 20 ) are generated by alkylation of [(η5‐C5Me5)M(NtBu)Cl3] with PhCH2MgCl via α‐H abstraction. Based on nmr data a trend of decreasing donor capability of the ligands [NtBu]2— > [O]2— > [CHR]2— ? 2 [CH3]— > 2 [Cl]— emerges. 相似文献
Deprotonation of the aminophosphanes Ph2PN(H)R 1a – 1h [R = tBu ( 1a ), 1‐adamantyl ( 1b ), iPr ( 1c ), CPh3 ( 1d ), Ph ( 1e ), 2,4,6‐Me3C6H2 (Mes) ( 1f ), 2,4,6‐tBu3C6H2 (Mes*) ( 1g ), 2,6‐iPr2C6H3 (DIPP) ( 1h )], followed by reactions of the phosphanylamide salts Li[Ph2PNR] 2a , 2b , 2g , and 2h with the P‐chlorophosphaalkene (Me3Si)2C=PCl, and of 2a – 2g with (iPrMe2Si)2C=PCl, gave the isolable P‐phosphanylamino phosphaalkenes (Me3Si)2C=PN(R)PPh2 3a , 3b , 3g , and (iPrMe2Si)2C=PN(R)PPh2 4a – 4g . 31P NMR spectra, supported by X‐ray structure determinations, reveal that in compounds 2a , 2b , 3a , and 3b , with bulky N‐alkyl groups the Si2C=P–N–P skeleton is non‐planar (orthogonal conformation), whereas 3g , 3h , and 4g with bulky N‐aryl groups exhibit planar conformations of the Si2C=P–N–P skeleton. Solid 3g and 4g exhibit cisoid orientation of the planar C=P–N–C units (planar I) but in solid 3h the transoid rotamer is present (planar II). From 3g , 4d , and 4g mixtures of rotamers were detected in solution by pairs of 31P NMR patterns ( 3h : line broadening). 相似文献
Synthesis and X‐Ray Structure Determination of iso ‐Butylimido Galliummethyl, [CH3Ga–NCH2CH(CH3)2]6 The thermal decomposition of [Me2Ga–N(iBu)SnMe3]2 (prepared by the reaction of [Me2SnNiBu]3 with GaMe3 in a 1:3 molar ratio) in an evacuated, sealed tube at 160°C forms [MeGaNiBu]6 in high yield and SnMe4. Mass, 1H and 13C NMR as well as some IR and Raman spectroscopic data are given and the crystal structure of this cage molecule with a hexagonal prismatic Ga6N6 skeleton has been determined. 相似文献
The synthesis of an N‐heterocyclic silylene‐stabilized digermanium(0) complex is described. The reaction of the amidinate‐stabilized silicon(II) amide [LSiN(SiMe3)2] ( 1 ; L=PhC(NtBu)2) with GeCl2?dioxane in toluene afforded the SiII–GeII adduct [L{(Me3Si)2N}Si→GeCl2] ( 2 ). Reaction of the adduct with two equivalents of KC8 in toluene at room temperature afforded the N‐heterocyclic carbene silylene‐stabilized digermanium(0) complex [L{(Me3Si)2N}Si→ Ge?Ge←Si{N(SiMe3)2}L] ( 3 ). X‐ray crystallography and theoretical studies show conclusively that the N‐heterocyclic silylenes stabilize the singlet digermanium(0) moiety by a weak synergic donor–acceptor interaction. 相似文献
Summary: The metallocenes rac‐C2H4(Ind)2ZrCl2 ( 1 ), rac‐Me2Si(Ind)2ZrCl2 ( 2 ), and rac‐Me2Si(2‐Me‐benz[e]Ind)2ZrCl2 ( 3 ) efficiently copolymerize propene and 5‐vinyl‐2‐norbornene (VNB). 1 and 2 give a high VNB content and high productivities, whereas 3 gives moderate incorporation. Surprisingly, precatalysts 1 and 2 , which have very closely related structures, showed very different reactivities toward VNB, with 1 having a greater affinity for VNB than for propene. The copolymers are quantitatively converted into polyolefins with polar functionalities.