Antipodal shielding effects in the boron-11, carbon-13, and phosphorus-31 nuclear magnetic resonance spectra of icosahedral carborane derivatives

Siedle, A. R.; Bodner, George M.; Garber, A. R.; Beer, Don C.; Todd, Lee J.

doi:10.1021/ic50140a006

Cited by 63 publications

(13 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, chlorination of the BH vertices leads to a surprisingly large upfield shift of the B1 atom (10.7 ppm in CD 3 CN) and results in a reversed order of all four 11 B NMR signals compared to the non‐chlorinated anion. An upfield shift of the respective antipodal BH vertex was already described for dicarba‐ closo ‐dodecaboranes, metallocarboranes, and phosphocarboranes after halogenation 18. This so‐called antipodal shift shows a linear correlation for different substituents with the 13 C shift of the para ‐carbon atom in monosubstituted benzenes 19.…”

Section: Resultsmentioning

confidence: 63%

“…An upfield shift of the respective antipodal BÀH vertex was already described for dicarba-closo-dodecaboranes, metallocarboranes, and phosphocarboranes after halogenation. [18] This so-called antipodal shift shows a linear correlation for different substituents with the 13 C shift of the para-carbon atom in monosubstituted benzenes. [19] A meta-effect, which occurs after dibromination of 1,2-B 10 H 10 C 2 H 2 , and leads to an upfield shift of the 11 B resonance of the boron atoms in metaposition to the brominated B-vertices by about 1.6 ppm has also been reported.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻

Bolli

Derendorf

Jenne

et al. 2014

Chemistry A European J

View full text Add to dashboard Cite

The weakly coordinating anion [Me3 NB12 Cl11 ](-) has been prepared by a simple two-step procedure. The anion [Me3 NB12 Cl11 ](-) is easily obtained in batches of up to 20 g by chlorination of the known [H3 NB12 H11 ](-) anion with SbCl5 at about 190 °C and subsequent N-methylation with methyl iodide. Starting from Na[Me3 NB12 Cl11 ], several synthetically useful salts with reactive cations ([NO](+) , [Ph3 C](+) , and [(Et3 Si)2 H](+) ) were prepared. Full spectroscopic (NMR, IR, Raman, TGA, MS) characterization and single-crystal X-ray diffraction studies confirmed the identity and purity of the products. The thermal, chemical, and electrochemical stability as well as the basicity of the [Me3 NB12 Cl11 ](-) anion is similar to that of the structurally related weakly coordinating 1-carba-closo-dodecaborate and closo-dodecaborate anions. The facile preparation of the [Me3 NB12 Cl11 ](-) anion and its ideal chemical and physical properties make it a cheap alternative to other classes of weakly coordinating anions.

show abstract

Section: Resultsmentioning

confidence: 63%

Section: Introductionmentioning

confidence: 99%

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻

Bolli

Derendorf

Jenne

et al. 2014

Chemistry A European J

View full text Add to dashboard Cite

show abstract

“…An analogous complex with composition 8,3-(s,Z 2 -PhCH=CPh)-1,2-Me 2 -3,3-(CO) 2 -3-Ph 3 P-3,1,2-MoC 2 B 8 H 8 (68) was prepared by the rearrangement of 1,2-Me 2 -3-CO-3-Ph 3 P-3-(Z 2 -PhC:CPh)-3,1,2-MoC 2 B 9 H 9 in dichloromethane at room temperature, which is evidence for the formation of the acetylene complex in the first step of the reaction of metallacarborane with acetylene. 117 (74).…”

Section: Substitution In 12-vertex Metallacarboranesmentioning

confidence: 99%

Substitution reactions at boron atoms in metallacarboranes

Bregadze¹,

Тимофеев²,

Sivaev³

et al. 2004

Russ. Chem. Rev.

View full text Add to dashboard Cite

“…The para position permits additional examination of Heřmánek's 16 antipodal effect [17][18][19][20] [closo-1-CB 9 H 10 ] -Anion and New C-Substituted Derivatives Fig. 1 summarize the shift increments (∆δ) in 11 B NMR and 13 C NMR of the halogenated and methylated derivatives 3a-3e and compares them with the C-halogenated [closo-1-CB 11 H 12 ] -anions.…”

Section: Nmr Spectramentioning

confidence: 99%

Improved synthesis of [closo-1-CB9H10]– anion and new C-substituted derivatives

Ringstrand

Bateman

Shoemaker

et al. 2009

Collect. Czech. Chem. Commun.

View full text Add to dashboard Cite

Dedicated to Professor Jaromír Plešek on the occasion of his 80th birthday in recognition of his major contributions to cluster borane chemistry.The Brellochs method was utilized to gain access to the [closo-1-CB 9 H 10 ] -anion (1). Previous work describing the details of the synthesis of 1 via the [closo-2-CB 9 H 10 ] -anion (2) was brief and insufficient. Therefore, we report an optimized procedure for the synthesis of 1, the preparation of the unknown C-halogenated series using N-halosuccinimides and bis(benzenesulfonyl)fluoroamine, and the unknown C-methylated product using CH 3 I. NMR properties and regularities within the series were also investigated.Monocarbaborane anion [CB 9 H 10 ] -(1) 1 belongs to the group of anions of general formula [CB n H n+1 ] -, where the anionic charge is highly delocalized. These anions possess chemical, electrochemical and thermal stability; thus, they are useful in weakly coordinating and low-nucleophilic anion chemistry as were described by Reed and Strauss 2 . Out of this group, the [closo-1-CB 11 H 12 ] -anion is the most studied 3 because of its easy accessibility. However, new synthetic breakthroughs produced monocarbaboranes via Brellochs reactions 4-6 of aldehydes with nido-B 10 H 14 , starting an accelerated expansion in sub-icosahedral monocarbaborane chemistry and revealing compounds with highly desirable characteristics.

show abstract

Antipodal shielding effects in the boron-11, carbon-13, and phosphorus-31 nuclear magnetic resonance spectra of icosahedral carborane derivatives

Cited by 63 publications

References 1 publication

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻

Substitution reactions at boron atoms in metallacarboranes

Improved synthesis of [closo-1-CB9H10]– anion and new C-substituted derivatives

Contact Info

Product

Resources

About

Antipodal shielding effects in the boron-11, carbon-13, and phosphorus-31 nuclear magnetic resonance spectra of icosahedral carborane derivatives

Cited by 63 publications

References 1 publication

Synthesis and Properties of the Weakly Coordinating Anion [Me3NB12Cl11]−

Synthesis and Properties of the Weakly Coordinating Anion [Me3NB12Cl11]−

Substitution reactions at boron atoms in metallacarboranes

Improved synthesis of [closo-1-CB9H10]– anion and new C-substituted derivatives

Contact Info

Product

Resources

About

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻

Synthesis and Properties of the Weakly Coordinating Anion [Me₃NB₁₂Cl₁₁]⁻