Zur reaktion von metall-koordiniertem kohlenmonoxid mit yliden: XI. Einige neuartige η1-vinyl-komplexe des eisens durch deprotonierung kationischer carbenkomplexe mit trimethyl(methylen)phosphoran

Novel η¹-vinyl complexes of the type Cp(CO)(L)FeC(OMe)C(R)R′ (R = R′ = H, Me; R = H, R′ = Me; L = Me₃P, Ph₃P) are obtainied via methylation of the acyl complexes Cp(CO)(L)FeC(O)R (R = Me, Et, i-Pr) with MeOSO₂F and subsequent deprotonation of the resulting carbene complexes [Cp(CO)(L)FeC(OMe)R]SO₃F with the phosphorus ylide Me₃PCH₂. The same procedure can be applied for the synthesis of the pentamethylcyclopentadienyl derivative C₅Me₅(CO)(Me₃P)FeC(OMe)CH₂, while treatment of the hydroxy or siloxy carbene complexes [Cp(CO)(L)FeC(OR)Me]X (R = H, Me₃Si; X = SO₃CF₃) with Me₃CH₂ results in the transfer of the oxygen bound electrophile to the ylidic carbon. Some remarkable spectroscopic properties of the new complexes are reported.     

Evidence for σ-π interaction in some allyltin compounds. UV photoelectron spectroscopy and LCBO calculations

A series of allyltin compounds, R_3-nCl_nSnCH₂CH=CH₂ (R = Me, n-Bu; n = 0-2) and Ph₃SnCH₂CH=CH₂, have been studied by gas-phase UV photoelectron spectroscopy, in order to determine the extent, if any, of σ-π conjugation (hyper-conjugation) between the σ(SnCH₂) bond and the π(CC) orbital of the allyl group. Analysis of the spectra, supported by a fragment analysis based on LCBO (Linear Combination of Bond Orbitals) calculations, indicated that the hyperconjugation operates for all the members of the series, the extent decreasing on passing from R = Me to R = n-Bu and, within each series, with increasing n.     

‘Anomalous’ 2J(Sn?H) coupling in mono– and dichloromethyltin compounds

The linear relationship between the coupling constants ¹J(Sn? ¹³C) and ²J(Sn? H), observed for a number of organotin compounds, does not hold for coupling in the Sn? CH_nCl_3?n group of mono- and dichloromethyltin compounds. A complete determination of all NMR parameters of the compounds Me₃Sn-CH_nCl_3?n (n = 0 to 3) shows no further anomalies, indicating that steric factors must be responsible for the unusually low values of ²J(Sn? H) in the SnCH_nCl_3?n group. Molecular weight measurements support this theory, showing that the chlorine-containing compounds are associated.     

Synthesis and Complexation Study of New Aminoalkynyl−amidinate Ligands

The current library of amidinate ligands has been extended by the synthesis of two novel dimethylamino-substituted alkynylamidinate anions of the composition [Me₂N−CH₂−C≡C−C(NR)₂]⁻ (R = ⁱPr, cyclohexyl (Cy)). The unsolvated lithium derivatives Li[Me₂N−CH₂−C≡C−C(NR)₂] ( 1 : R = ⁱPr, 2 : R = Cy) were obtained in good yields by treatment of in situ-prepared Me₂N−CH₂−C≡C−Li with the respective carbodiimides, R−N=C=N−R. Recrystallization of 1 and 2 from THF afforded the crystalline THF adducts Li[Me₂N−CH₂−C≡C−C(NR)₂] ⋅ nTHF ( 1 a : R = ⁱPr, n=1; 2 a : R = Cy, n=1.5). Precursor 2 was subsequently used to study initial complexation reactions with selected di- and trivalent transition metals. The dark red homoleptic vanadium(III) tris(alkynylamidinate) complex V[Me₂N−CH₂−C≡C−C(NCy)₂]₃ ( 3 ) was prepared by reaction of VCl₃(THF)₃ with 3 equiv. of 2 (75 % yield). A salt-metathesis reaction of 2 with anhydrous FeCl₂ in a molar ratio of 2 : 1 afforded the dinuclear homoleptic iron(II) alkynylamidinate complex Fe₂[Me₂N−CH₂−C≡C−C(NCy)₂]₄ ( 4 ) in 69 % isolated yield. Similarly, treatment of Mo₂(OAc)₄ with 3 or 4 equiv. of 2 provided the dinuclear, heteroleptic molybdenum(II) amidinate complex Mo₂(OAc)[Me₂N−CH₂−C≡C−C(NCy)₂]₃ ( 5 ; yellow crystals, 50 % isolated yield). The cyclohexyl-substituted title compounds 2 a , 4 , and 5 were structurally characterized through single-crystal X-ray diffraction studies.     

Functionally substituted organotin compounds I. Addition of thiols to alkenyltin compounds

3-(Trialkylstannyl)propyl aryl sulphides (R₃SnCH₂CH₂CH₂SR′; R = Me, Et, Bu; R′ = Ph, p-tolyl) were prepared by the addition of arenethiols to allyltrialkyltin compounds. Preferential cleavage of the allyl group by the reaction R₃SnCH₂CHCH₂+R′SH→R₃SnSR′+CH₃CHCH₂ occurred when R = R′ = Bu and R = R′ = Ph. Diallyltin dibromide and benzenethiol gave stannous bromide. Mössbauer parameters of the products are recorded.     

Funktionell substituierte zinnorganische verbindungen v. st]Phosphono- Und phosphonylmethyl-triorganostannane

The synthesis of phosphono- and phosphonylmethyl-triorganostannanes R₃SnCH₂P(O)(OR′)R′′ (R′′  OR′, C₆H₅) via an Arbuzov reaction of R₃SnCH₂I with P(OR′)₃ or C₆H₅P(OR′)₂ (R′′  CH₃, C₂H₅) is described. The new compounds have been studied with regard to their behaviour towards electrophilic (Br₂, HCl, HgBr₂) and nucleophilic (NaOH, LiAlH₄, LiR) agents. Their reaction with chlorophenylphosphines followed by reduction with LiAlH₄ yields the unsymmetrical methylenebis(phosphines) C₆H₅P(R)CH₂PH₂ (R  H, C₆H₅). The title compounds add to the carbonyl group of aldehydes and the CN bond of phenylisocyanate.     

Diorganophosphinoalkyl-dimethylzinnchloride: Synthese,struktur und reaktionsverhalten

Phosphinoalkylchlorostannanes of the type Me₂Sn(Cl)(CH₂)_nPR¹R² (n = 2,3) (I–VIII) are synthesized by a redistribution reaction of the tetraorganostannanes Me₃Sn(CH₂)_nPR¹R² (n = 2,3) with trimethyltin chloride. In non-coordinating solvents the tin atom in I–IV is tetracoordinated, whereas NMR data indicate an intramolecular SnP interaction for V–VIII. In the solid state compound III exists as an 1:1 adduct with trimethyltin chloride. With methyl iodide compounds I–VIII form the phosphonium stannates Me₂SnCl) (I) (CH₂)_nP+R¹R²Me (XI–XIII). Compounds I–VIII are suitable starting materials for the synthesis of the tin hydrides Me₂Sn(H)(CH₂)_nPR¹R² (XIV–XVI) and the distannanes [Me₂Sn(CH₂)_nPR¹R²]₂ (XVII–XIX). The reaction of I–VIII with sodium in liquid ammonia or with lithium in THF, respectively, yields solutions of the corresponding alkali stannides Me₂Sn(M)(CH₂)_nPR¹R² (M = Li, Na).     

Ligandverhalten von P‐funktionellen Organozinnhalogeniden: Nickel(II)‐, Palladium(II)‐ und Platin(II)‐halogenid‐Komplexe mit Me2(Cl)SnCH2CH2PPh2

Ligand Behaviour of P‐functional Organotin Halides: Nickel(II), Palladium(II), and Platinum(II) Complexes with Me₂(Cl)SnCH₂CH₂PPh₂ Me₂(Cl)SnCH₂CH₂PPh₂ ( 1 ) reacts with Ni^II, Pd^II, and Pt^II halides in molar ratio 2 : 1 forming the complexes [MX₂{PPh₂CH₂CH₂Sn(Cl)Me₂}₂] (M = Ni, Pd, Pt; X = Cl, Br) ( 3 – 6 , 9 , 10 ) ( 7 , 8 : M = Ni; Br instead of Cl). The nickel complexes were isolated and characterized both as the planar ( 3 , 5 , 7 ) and the tetrahedral ( 4 , 6 , 8 ) isomer. Crystal structure analyses and NMR data indicate for the planar nickel complexes 3 , 5 , 7 and [MCl₂{PPh₂CH₂CH₂Sn(Cl)Me₂}₂] ( 9 : M = Pd; 10 : M = Pt) the existence of intra and intermolecular M–Hal…Sn bridges. In a ligand : metal molar ratio of 3 : 1 the complexes [M^éCl{PPh₂CH₂CH₂Sn^⊖Cl₂Me₂}{PPh₂CH₂CH₂Sn(Cl)Me₂}₂] ( 11 : M = Pd; 12 : M = Pt) are formed which represent intramolecular ion pairs. By dehalogenation of [PdCl₂{PPh₂CH₂CH₂Sn(Cl)Me₂}₂] ( 9 ) with sodium amalgam and graphite potassium (C₈K), respectively, the palladacycles cis‐[Pd{PPh₂CH₂CH₂SnMe₂}₂] ( 13 ) and trans‐[Pd(Cl)PPh₂CH₂CH₂SnMe₂{PPh₂CH₂CH₂Sn(Cl)Me₂}] ( 14 ) are formed. From the compounds 1 , 3 , 9 , 11 , and 12 the crystal structures are determined. All compounds are characterized by ¹H, ³¹P, and ¹¹⁹Sn NMR spectroscopy.     

REACTIONS OF A PHOSPHORANIMINE ANION WITH SOME ORGANIC ELECTROPHILES

Abstract

The reactions of a variety of electrophiles with the N-silyl-P-trifluoroethoxyphosphoranimine anion Me₃Sin°P(Me)(OCH₂CF₃)CH^? ₂ (1a), prepared by the deprotonation of the dimethyl precursor Me₃SiN[dbnd]P(OCH₂CF₃)Me₂ (1) with n-BuLi in Et₂O at-78°C, were studied. Thus, treatment of 1a with alkyl halides, ethyl chloroformate, or bromine afforded the new N-silylphosphoranimine derivatives Me₃SiN[dbnd]P(Me)(OCH₂CF₃)CH₂R [2: R = Me, 3: R = CH₂Ph, 4: R = CH[sbnd]CH₂, 5: R = C(O)OEt, and 6: R = Br]. In another series, when 1a was allowed to react with various carbonyl compounds, 1,2-addition of the anion to the carbonyl group was observed. Quenching with Me₃SiCl gave the O-silylated products Me₃SiN[dbnd]P(Me)(OCH₂CF₃)CH₂°C(OSiMe₃)R¹R² [7: R ¹ = R ² = Me; 8: R ¹ = Me, R ² = Ph; 9: R¹ = Me, R ² = CH[sbnd]CH₂; and 10: R ¹ = H, R ² = Ph]. Compounds 2–10 were obtained as distillable, thermally stable liquids and were characterized by NMR spectroscopy (¹H, ¹³C, and ³¹P) and elemental analysis.     

Reactions of [Cp*Ru(H2O)(NBD)]+ with alkynes

Formal [2 + 2 + 2] addition reactions of [Cp*Ru(H₂O)(NBD)]BF₄ (NBD = norbornadiene) with PhC?CR (R = H, COOEt) give [Cp*Ru(η⁶‐C₆H₅? C₉H₈R)] BF₄ (1a, R = H; 2a, R = COOEt). Treatment of [Cp*Ru(H₂O)(NBD)]BF₄ with PhC?C? C?CPh does not give [2 + 2 + 2] addition product, but [Cp*Ru(η⁶‐C₆H₅? C?C? C?CPh)] BF₄(3a). Treatment of 1a, 2a, 3a with NaBPh₄ affords [Cp*Ru(η⁶‐C₆H₅? C₉H₈R)] BPh₄ (1b, R = H; 2b, R = COOEt) and [Cp*Ru(η⁶‐C₆H₅? C?C? C?CPh)] BPh₄(3b). The structures of 1b, 2b and 3b were determined by X‐ray crystallography. Copyright © 2007 John Wiley & Sons, Ltd.     

Reaktionen von metall-koordiniertem kohlenmonoxid mit yliden: XVII. Darstellung eines molybdän- und wolframkomplexes mit η3-gebundenem trimethylsiloxybutenon-liganden durch silylierung der phosphonium-metall-enolat-vorstufe

The reaction of the phosphonium metallates Me₄P[C₅R₅(CO)(Me₃P)$\text{MC(O)=CHC(O}$)R′] (M = W, R = H, R′ = Et (1a); M = Mo, R = Me, R′ = Me (1b)) with the silylating reagent Me₃SiOSO₂CF₃ yields the neutral complexes C₅R₅(CO)(Me₃P)$\text{MC(OSiMe}{}_3\text{)=CHC(O}$)R (2a, 2b) bearing a chelating O(2), C(4)-trimethylsiloxybutenone ligand. The structure of the new compounds is established by the IR, ¹H and ³¹P NMR spectra.     

Synthesis and Characterisation of 1‐[9‐(H,Me3Si,Me3Ge,Me3Sn)9‐Fluorenyl]‐3,7,10‐trimethylgermatranes. The Crystal Structure Analysis of 1‐(9‐Fluorenyl)‐3,7,10‐trimethylgermatrane

The title compounds, viz. C₁₃H₈(R)Ge · (OCHMeCH₂)₃N ( 1 : R = H, 2 : R = Me₃Si; 3 : R = Me₃Ge) were prepared as mixtures of diastereomers by the reaction of N(CH₂CHMeOSnAlk₃)₃ ( 7 : Alk = Et; 8 : Alk = Bu) with C₁₃H₈(R)GeBr₃ ( 4 : R = H, 5 : R = Me₃Si; 6 : R = Me₃Ge), respectively. The synthesis of C₁₃H₈(Me₃Sn)Ge · (OCHMeCH₂)₃N ( 13 ) by the reaction of germatrane ( 1 ) with Me₃SnNMe₂ is reported. Identity and structures were established by elemental analyses, ¹H and ¹³C NMR spectroscopy and mass spectrometry. The crystal structure of 1 was determined by X‐ray diffraction methods.     

Zur Reaktion von Metall-koordinierten Kohlenmonoxid mit Yliden XXII. Bis(diphenylphosphino)methanid-Eisen-Komplexe Cp(L)Fe(Ph2PCHPPh2) (L = CO,Me3P)

The reaction of [Cp(CO)(dppm)Fe]BF₄ (1a) with the phosphorus ylide Me₃PCH₂ yields the novel bis(phosphino)methanideiron complex Cp(CO)Fe(Ph₂PCHPPh₂) (2), which upon photolysis in the presnece of Me₃P is converted into Cp(Me₃P)Fe(Ph₂PCHPPh₂ (3). Reaction of 2 with MeOSO₂CF₃ gives a mixture of the iron salts [(Cp(CO)Fe(Ph₂PCR(R′)PPh₂)]CF₃SO₃ (R = R′ = H (1b), R = R′ = Me (6) and R = H, R′ = Me (syn/anti-4)).     

Activation of CH bonds in acetylene and terminal alkynes by rhodium(I) species. Crystal structure of cis-(ethynyl)hydride [(NP3)Rh(H)(CCH)]BPh4·1.5C4H8O (NP3 = N(CH2CH2PPh2)3)

The 16-electron fragment (NP₃)Rh⁺ inserts in a highly stereospecific manner across CH bonds from acetylene and 1-alkynes to give the octahedral cis-(alkynyl)hydrides [(NP₃)Rh(H)(CCR)]BPh₄ (R = H, Ph, COOEt). The structure of the cis-(ethynyl)hydride [(NP₃)Rh(H)(CCH)]BPh₄ · 1.5 THF has been established by X-ray diffraction. The trigonal bipyramidal rhodium(I) complex [(NP₃)RhH], reacts with terminal alkynes to give H₂ and the neutral σ-acetylides [(NP₃)Rh(CCR)] (R = Ph, COOEt). These undergo metathesis between terminal alkynes and the σ-acetylide ligand through a mechanism involving consecutive breaking and making of CH bonds.     

Synthese und Struktur eines Pentaalkylchlorohexastibans Sb6R5Cl [R = (Me3Si)2CH]

Synthesis and Structure of Pentaalkylchlorohexastibane Sb₆R₅Cl [R = (Me₃Si)₂CH] The reaction of RSbCl₂ [R = (Me₃Si)₂CH] with Na‐K alloy in tetrahydrofuran gives besides the known rings Sb_nR_n (n = 3, 4), (Me₃Si)₂CH₂ and the pentaalkylchlorohexastibane Sb₆R₅Cl ( 1 ). 1 was characterized by spectroscopic methods (MS, ¹H‐, ¹³C‐NMR, X‐ray diffraction). The structure of 1 consists of a folded four membered antimony ring in the all‐trans configuration with three alkyl groups and one Sb(R)—Sb(R)Cl fragment as substituents.     

Alternativ-Liganden. XXIV. Rhodium(I)-Komplexe mit P-Donor-und Sn- bzw. B-Akzeptor-Liganden

Alternative Ligands. XXIV. Rhodium(I) Complexes with P-Donor and Sn- or B-Acceptor Ligands Donor/acceptor ligands of the type Me₂PCH₂CH₂SnMe₃ (1) , (Me₂PCH₂CH₂)₂SnMe₂ (2) , and Me₂PCMe=CMeBMe₂ (3) , respectively, have been prepared by hydrostannlation of Me₂PVi with Me₃SnH or Me₂SnH₂ and by a multistep synthesis via Na[Me₃BH], Na[Me₃BC?;CMe] using Me₂PCI as partner, respectively. The new ligands were used to produce the Rh(I) complexes RhCI(CO)(Me₂PCH₂CH₂SnMe₃)₂ (5) , RhCI(CO)(Me₂PCH₂CH₂)₂SnMe₂ (7), and RhCI(CO)(Me₂PCMe=CMeBMe₂)₂ (8) by reactions of Rh(CO)₂CH₂ (4) with the corresponding ligands. In addition, the VASKA type compounds RhCI(CO)(Me₂PVi)₂ (6) and RhCI(CO)(PMe₃)₂ were prepared in order to test an alternative route to 5 or to from the known adduct RhCI(CO)(PMe₃)₂. BBr₃ (9) . RhBr(CO)(PMe₃)₂ (10) and the binuclear system [RhBr(CO)PMe₃]₂ (11) were identified spectroscopically after working up the 1:1 reaction mixture of RhCI(CO)(PMe₃)₂ and BBr₃. Reasonable pathways are suggested for their formation. ?Metallbase”?/acceptor interaction show up, on the one hand, in following reactions in case of the ligands with Sn acceptors, on the other hand, in significant changes of spectroscopic data for 8 . New compounds of sufficient stability were characterized by analytical (C, H) and spectroscopic (MS, IR. NMR) investigations.     

Silicon‐ and Tin‐Containing Open‐Chain and Eight‐Membered‐Ring Compounds as Bicentric Lewis Acids toward Anions

Herein, we report the syntheses of silicon‐ and tin‐containing open‐chain and eight‐membered‐ring compounds Me₂Si(CH₂SnMe₂X)₂ ( 2 , X=Me; 3 , X=Cl; 4 , X=F), CH₂(SnMe₂CH₂I)₂ ( 7 ), CH₂(SnMe₂CH₂Cl)₂ ( 8 ), cyclo‐Me₂Sn(CH₂SnMe₂CH₂)₂SiMe₂ ( 6 ), cyclo‐(Me₂SnCH₂)₄ ( 9 ), cyclo‐Me_(2?n)X_nSn(CH₂SiMe₂CH₂)₂SnX_nMe_(2?n) ( 5 , n=0; 10 , n = 1, X= Cl; 11 , n=1, X= F; 12 , n=2, X= Cl), and the chloride and fluoride complexes NEt₄[cyclo‐ Me(Cl)Sn(CH₂SiMe₂CH₂)₂Sn(Cl)Me?F] ( 13 ), PPh₄[cyclo‐Me(Cl)Sn(CH₂SiMe₂CH₂)₂Sn(Cl)Me?Cl] ( 14 ), NEt₄[cyclo‐Me(F)Sn(CH₂SiMe₂CH₂)₂Sn(F)Me?F] ( 15 ), [NEt₄]₂[cyclo‐Cl₂Sn(CH₂SiMe₂CH₂)₂SnCl₂?2 Cl] ( 16 ), M[Me₂Si(CH₂Sn(Cl)Me₂)₂?Cl] ( 17 a , M=PPh₄; 17 b , M=NEt₄), NEt₄[Me₂Si(CH₂Sn(Cl)Me₂)₂?F] ( 18 ), NEt₄[Me₂Si(CH₂Sn(F)Me₂)₂?F] ( 19 ), and PPh₄[Me₂Si(CH₂Sn(Cl)Me₂)₂?Br] ( 20 ). The compounds were characterised by electrospray mass‐spectrometric, IR and ¹H, ¹³C, ¹⁹F, ²⁹Si, and ¹¹⁹Sn NMR spectroscopic analysis, and, except for 15 and 18 , single‐crystal X‐ray diffraction studies.     

Molekülstruktur von 2,2-Bis(diisopropoxyphosphonyl)propyl-methylzinndibromid

Molecular Structure of 2,2-Bis(diisopropoxyphosphonyl)propyl Methyltin Dibromide By methylation of Me₃SnCH₂CH[P(O)(OPr?i)₂]₂ with NaH/MeI Me₃SnCH₂C(Me)[P(O)(OPr?i)₂]₂ ( 1 ) is obtained, which is converted by bromine into the dibromide MeBr₂SnCH₂C(Me)[P(O)(OPr?i)₂]₂ ( 2 ). An X-ray crystal structure analysis shows 2 to be monomeric. The tin atom is situated in the centre of a distorted octahedron, in which the functional substituent is intramolecular coordinated as tridentate ligand in a facial mode. The two organo groups are arranged in trans-position (C? Sn? C 155.1°), whereas the oxygen and bromine atoms are orientated cis to each other. The six-membered ring of the bicyclic molecular fragment of 2 which results from the coordination of the functional organo group to the tin atom shows a boat-conformation, whereas the two five-membered rings exist in twist-conformations. Multinuclear n.m.r. and i.r. data show that 2 retains its solid state structure also in nonpolar solvents.     

1‐Silacyclopent‐2‐enes and 1‐silacyclohex‐2‐enes bearing functionally substituted silyl groups in 2‐positions. Novel electron‐deficient Si?H?B bridges

The reactions of alkyn‐1‐yl(vinyl)silanes R₂Si[C?C‐Si(H)Me₂]CH?CH₂ [R = Me (1a), Ph (1b)], Me₂Si[C?C‐Si(Br)Me₂]CH?CH₂ (2a), and of alkyn‐1‐yl(allyl)silanes R₂Si[C?C‐Si(H)Me₂]CH₂CH?CH₂ (R = Me (3a), R = Ph (3b)] with 9‐borabicyclo[3.3.1]nonane in a 1:1 ratio afford in high yield the 1‐silacyclopent‐2‐ene derivatives 4a, b and 5a, and the 1‐silacyclohex‐2‐ene derivatives 6a, b, respectively, all of which bear a functionally substituted silyl group in 2‐position and the boryl group in 3‐position. This is the result of selective intermolecular 1,2‐hydroboration of the vinyl or allyl group, followed by intramolecular 1,1‐organoboration of the alkynyl group. In the cases of 4a, b, potential electron‐deficient Si? H? B bridges are absent or extremely weak, whereas in 6a,b the existence of Si? H? B bridges is evident from the NMR spectroscopic data (¹H, ¹¹B, ¹³C and ²⁹Si NMR). The molecular structure of 4b was determined by X‐ray analysis. Copyright © 2005 John Wiley & Sons, Ltd.     

Versatile Conversion of N‐Heterocyclic Silylene to Silyl Metal Compounds by Insertion of Divalent Silicon into Metal–Carbon and Metal–Hydrogen Bonds

The facile one‐pot reaction of the stable N‐heterocyclic silylene LSi: 1 (L?(ArN)C(?CH₂) CH?C(Me)(NAr), Ar=2,6‐iPr₂C₆H₃) with Me₂Zn, Me₃Al, H₃Al‐NMe₃, and MeLi has been investigated. The silicon(II) atom in 1 is capable of insertion into the corresponding M? C and Al? H bonds under very mild reaction conditions. Thus, Me₂Zn furnishes the bis(silyl) zinc complex LSi(Me)ZnSi(Me)L 2 as the sole product, irrespective of the molar ratio of the starting materials applied. Moreover, the reactions of 1 with Me₃Al, H₃Al‐NMe₃, and MeLi lead directly to the 1,1‐addition products LSi(Me)(Al(thf)Me₂) 3 , LSi(H)(AlH₂(NMe₃)) 4 , and LSi(Me)Li(thf)₃ 5 , respectively. All new compounds 2 – 5 were fully characterized by multinuclear NMR spectroscopy, mass spectrometry, elemental analyses, and single‐crystal X‐ray diffraction analyses.