Unexpected Formation and Crystal Structure of the Highly Symmetric Carbanion [C(SiCl3)3]–

Böhme, Uwe; Gerwig, Maik; Gründler, Franziska; Brendler, Erica; Kroke, Edwin

doi:10.1002/ejic.201600763

Cited by 12 publications

(22 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For a discussion of the trigonal‐planar anion [ 1 ] − , see Refs. and the Supporting Information of this paper. The Si and Ge centers in [ 2 ] − and [ 3 ] − are strongly pyramidalized [Σ(SiSiSi)=290.0°, Σ(SiGeSi)=285.5°].…”

Section: Figurementioning

confidence: 99%

“…[14] (iii)The challenging activation of Si 2 Me 6 ,o nt he other hand, requirest he presence of powerful transition-metal catalysts. [15] Representatives of exhaustively Cl 3 Si-substituted tetrelides are the methanide [(Cl 3 Si) 3 C] À ([1] À ) [16][17][18] and the silanide[ (Cl 3 Si) 3 Si] À ([2] À ). [19,20] A correspondingu ncharged species A also exists ( Figure 1).…”

mentioning

confidence: 99%

See 1 more Smart Citation

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Teichmann

Kunkel

Georg

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

Trichlorosilylated tetrelides [(Cl3Si)3E]− have been prepared by adding 1 equiv of a soluble Cl− salt to (Cl3Si)4Si (E=Si) or 4 Si2Cl6/GeCl4 (E=Ge). To assess their donor qualities, the anions [(Cl3Si)3E]− (E=C, Si, Ge) have been treated with BCl3, AlCl3, and GaCl3. Both BCl3 and GaCl3 give 1:1 adducts with the anionic centers. AlCl3 leads to Cl− abstraction from [(Cl3Si)3E]− with formation of (Cl3Si)4E (E=Si or Ge). (Cl3Si)4Ge is cleanly converted to the perhydrogenated (H3Si)4Ge by use of Li[AlH4]. Another case of Cl− abstraction was observed for [(Cl3Si)3Ge⋅GaCl3]−, which reacts with GaCl3 to afford the neutral dimer [(Cl3Si)3Ge−GaCl2]2.

show abstract

Section: Figurementioning

confidence: 99%

mentioning

confidence: 99%

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Teichmann

Kunkel

Georg

et al. 2019

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…[62] [C(SiCl 3 ) 3 ] À (5) and C(SiCl 3 ) 4 (6) have been included in the following considerations. [13,26] The geometry of the anion 5 differs from the [B(SiCl 3 ) 4 ] À ion, since it has trigonal planar symmetry. C(SiCl 3 ) 4 (6) has the same tetrahedral geometry like [B(SiCl 3 ) 4 ] À and both are isoelectronic.…”

Section: Quantum Chemical Analysismentioning

confidence: 99%

“…This is in contrast to the CÀ Si bond in 5, which was characterized as highly polar closed shell interaction which is best described as dative bond. [13] The CÀ Si bond in 6 has an intermediate character with a Laplacian of electron density close to zero.…”

Section: Quantum Chemical Analysismentioning

confidence: 99%

“…Trichlorosilyl substituted anions of main group elements have been recently shifted into the focus of research. The following anions have been characterized since 2015: [C(SiCl 3 ) 3 ] À , [13,14,15] [Si(SiCl 3 ) 3 ] À , [16,17] [Ge(SiCl 3 ) 3 ] À , [16] [P(SiCl 3 ) 2 ] À , [18,19] and [S(SiCl 3 )] À . [19] Especially [P(SiCl 3 ) 2 ] À received considerable attention as synthon for the generation of phosphorus chemicals, that had previously only been available from white phosphorus (P 4 ).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Unexpected Formation of the Highly Symmetric Borate Ion [B(SiCl₃)₄]⁻

Bochmann¹,

Böhme

Brendler

et al. 2021

Eur J Inorg Chem

Self Cite

View full text Add to dashboard Cite

Disproportionation reactions of chlorosilane compounds in the presence of boron trichloride yield the compound H[B(SiCl 3 ) 4 ]. Spectroscopic analyses of the yellow-whitish solid with IR-, Raman-, and NMR-spectroscopy ( 29 Si, 11 B) show the presence of a highly symmetric anion containing boron, which is fourfold coordinated with silicon. Due to the high symmetry 1 J( 11 B, 29 Si) and even 1 J ( 10 B, 29 Si) couplings can be observed in the NMR spectra of the dissolved compound. The crystal structure analysis with a crystal obtained from toluene solution proves the existence of a highly symmetric borate anion, which is stabilized by four trichlorosilyl groups. The molecular structure consists of a para-protonated toluene cation and the weakly coordinating borate anion [B(SiCl 3 ) 4 ] À . Quantum chemical analysis of the tetrakis(trichlorosilyl)borate ion shows a negatively charged boron atom and the presence of polar SiÀ Cl and SiÀ B bonds. Highly reactive compounds [E(SiCl 3 ) n ] À which are stabilized solely by trichlorosilyl groups have been prepared with E=C, Si, Ge, P, S in recent years. The superacid H[B(SiCl 3 ) 4 ] represents a new member in this elusive compound family.

show abstract

Synthesis of Structurally Complex Silicon Frameworks through the First Sila‐Aldol Reaction

et al. 2017

View full text Add to dashboard Cite

Herein, we report on the first sila-aldol reaction, which emphasizes the tight connection between silicon and carbon chemistry.T his novel synthetic method provides straightforwarda ccess to 2-oxahexasilabicyclo[3.2.1]octan-8ide,astructurally complex silicon framework, in quantitative yield. Its structure was confirmed by NMR spectroscopya nd X-ray crystallography,a nd it displays ad istinctive chargetransfer transition. The complete mechanism of this highly selective rearrangement cascade is outlined and supported by density functional theory (DFT) calculations,w hich highlight the thermodynamic driving force and the low activation barriers of this powerful silicon-carbon bond-forming strategy.The classical aldol reaction, and in particular its power in the reversible formation and cleavage of carbon-carbon bonds,is one of the most important biosynthetic tools for the evolution of life on earth. [1] On the basis of this general strategy,namely the merging of two carbonyl compounds,s ynthetic chemists have put al ot of emphasis on stereoselective aldol reactions over the last couple of centuries to accomplish results comparable to those achieved by organisms and enzymes in nature. [2][3][4][5] These synthetic approaches include,f or example, the use of organocatalysts (amine-based systems), [4,6] chiral auxiliaries (Evans oxazolidinone route), [7] as well as chiral Lewis acids (e.g., Zn, Ag, Pd, and Cu complexes) [4,5,8] and bases. [9] Forsilicon-based compounds,however, such siliconcarbon bond-forming reactions have not been reported, although they must be considered as ap owerful alternative to standard coupling techniques,s uch as the Wurtz reaction and related methods, [10] hydrosilylation, [11] as well as transition-metal-catalyzed silicon-carbon coupling reactions. [12] Consequently,w es et out to explore the applicability of the sila-aldol reaction as an ovel synthetic method for the synthesis of complex silicon-carbon frameworks.B ased on this sila-aldol strategy,w hich induced an anionic rearrangement cascade,w ea chieved the selective formation of 2-oxahexasilabicyclo[3.2.1]octan-8-ide 1 (Scheme 1).We considered the intramolecular sila-aldol reaction as an optimal starting point for the development of this trans-formation as it should be entropically favored and employs highly symmetric starting materials.H owever,t he synthesis and isolation of such compounds,f or example, a,w-bis-(acyl)silanes,were previously not possible.Given our ongoing interest in the formation of cyclic acylsilanes, [13] we were now able to accomplish the synthesis of 1,4-bis-(acyl)cyclohexasilane 2 by reacting 1,4-dipotassium-1,4-bis-(trimethylsilyl)cyclohexasilane (3) [14] with two equivalents of mesitoyl chloride (MesCOCl) in diethyl ether (Et 2 O) at À78 8 8C. This reaction resulted in the clean formation of airstable and crystalline 1,4-bis(mesitoyl)cyclohexasilane (2)a s a1 :1 mixture of the trans and cis isomers in 72 %y ield (Scheme 2), an optimal and highly promising precursor molecule for our subsequent studies.T he ...

show abstract

Unexpected Formation and Crystal Structure of the Highly Symmetric Carbanion [C(SiCl₃)₃]^–

Cited by 12 publications

References 48 publications

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Unexpected Formation of the Highly Symmetric Borate Ion [B(SiCl₃)₄]⁻

Synthesis of Structurally Complex Silicon Frameworks through the First Sila‐Aldol Reaction

Contact Info

Product

Resources

About

Unexpected Formation and Crystal Structure of the Highly Symmetric Carbanion [C(SiCl3)3]–

Cited by 12 publications

References 48 publications

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Tris(trichlorosilyl)tetrelide Anions and a Comparative Study of Their Donor Qualities

Unexpected Formation of the Highly Symmetric Borate Ion [B(SiCl3)4]−

Synthesis of Structurally Complex Silicon Frameworks through the First Sila‐Aldol Reaction

Contact Info

Product

Resources

About

Unexpected Formation and Crystal Structure of the Highly Symmetric Carbanion [C(SiCl₃)₃]^–

Unexpected Formation of the Highly Symmetric Borate Ion [B(SiCl₃)₄]⁻