Polyhedral Borane Anions Research Articles

Ionic organoboranes. Part 6. The ousenes revisited; 11B NMR spectra of two polyhedral borane anions, a nido-carborane anion, and a closo-carborane with carbocyclic cationic tropenyliumyl substituents

The ousenes are a class of ionic or zwitterionic organoboranes in which polyhedral borane anions or carboranes have carbocyclic cationic tropenyliumyl ( cyclo-C 7H + 6) substituents. 11B Fourier transform NMR studies have been used to probe ground state electronic interaction between cage and ring. Tropenyliumyl substitution on B 12H 2− 12 or a closo-C 2B 10H 12 results in relatively minor electron withdrawal from the cage by a − I effect, while such substitution on B 10H 2− 10 or a nido-C 2B 9H 2− 12 results in significant − I withdrawal of electron density at the point of attachment and, in addition, strong + T electron donation from cage to ring by borons other than at the point of attachment. Coupled with previous studies these observations confirm that modification of ousene structure can vary cage to ring electronic interaction from negligible, through excited state charge transfer, to significant electron delocalization from ground state electron density donation from cage to ring, and suggests that the electrical properties of these materials may well be worth further study.

Palladium-Mediated Substitution Reactions of Polyhedral Borane Anions

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPalladium-Mediated Substitution Reactions of Polyhedral Borane AnionsSteve A. Jasper Jr., Richard B. Jones, John Mattern, John C. Huffman, and Lee J. ToddCite this: Inorg. Chem. 1994, 33, 25, 5620–5624Publication Date (Print):December 1, 1994Publication History Published online1 May 2002Published inissue 1 December 1994https://doi.org/10.1021/ic00103a005RIGHTS & PERMISSIONSArticle Views182Altmetric-Citations28LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (574 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information Get e-Alerts

Host-guest chemistry of an ion-complexation by macrocyclic multidentate Lewis acids

Abstract

Theoretical aspects of metal cluster chemistry

Abstract

Reactions of nitriles with polyhedral borane anions. Reductive cyclocondensation and carbon insertion reactions: syntheses of hypho-5-CH3-5,11,7,14-CNS2B7H9 and nido-6-CH3-5,6,9-C3B7H10

The reactions of the polyhedral borane anions arachno-S 2 B 7 H 8 − and arachno-C 2 B 7 H 12 − with acetonitrile have been explored and found to result in reduction of the nitrile and either the incorporation of a CN unit into the cage framework or a one-carbon insertion accompanied by deamination

Allowed and forbidden nature of diamond- square-diamond degenerate rearrangements in polyhedral boranes-a general topological analysis

The topological and orbital symmetry constraints governing the intramolecular rearrangements of closo -polyhedral borane anions have been analysed. If the diamond-square-diamond rearrangement process occurs through an intermediate of C 4 v symmetry it corresponds to a pseudo-90° rotation of the polyhedron. For deltahedra such an intermediate is only possible if there are a total of 4 p +1 ( p = 1, 2,...) boron atoms. These rearrangements are orbitally forbidden and consequently have high activation energies, e.g. B 5 H 2− 5 - and B 9 H 2− 9 -. If the diamond-square-diamond rearrangement proceeds through a C 2 v or C s intermediate it corresponds to a pseudo-reflection of the polyhedron and the process is symmetry allowed. Such symmetry allowed processes can occur for B 8 H 2− 8 and B 11 H 2− 22 .

Hexamethylbenzene-ruthenaborane and -osmaborane chemistry

An extensive suite of polyhedral metalloborane structural types is readily synthesizable by the reactions of [η 6-C 6Me 6)RuCl 2] 2 with polyhedral borane anions, and preliminary indications are that the osmium analogue [(η 6-C 6Me 6)OsCl 2] 2, prepared by a route analogous to that used for [(η 6-C 6Me 6)RuCl 2] 2, is an equally versatile metallaborane synthon.

Stability of polyhedral borane anions and carboranes

Polyhedral borane anions and carboranes that can be constructed formally from the interaction of rings and caps will be stable with six interstitial electrons. Interstitial electron count is obtained by summing the number of π electrons of the ring and the electrons of the caps involved in ring cap binding. Thus B7H7−2 (D5h) has 6 interstitial electrons (none from the B5H5 ring, two each from the twobh caps and two negative charge),mndo calculations on isoelectronic pyramidal molecules B6H6−4 (C5v), B5H5CH−3 (C5v), B5H5−4 (C4v), B4H4CH−3 (C4v), B4H4−4 (Td) and B3H3CH−3 (C3v) suggests a criterion based on the out-of-plane bendings of the ring B-H bonds to select the best combination of borocycles and BH or CH caps. Three-membered borocycle prefers CH cap, five-membered borocycle prefers BH cap. The preference of four-membered ring for BH or CH cap is not as pronounced. The extra stability of B12H12−2 arises from the geometry of the icosahedron. The relative stabilities ofnido andcloso carboranes follow from these rules.

Tetraorganophosphonium and tetraphenylarsonium salts of B 5H 8− and B 6H 9−

Eight new quaternary phosphonium or arsonium salts of the polyhedral borane anions B 5H 8 − and B 6H 9 − have been prepared in order to study the influence of cation size on stability. The salts are, indeed, considerably more stable than those previously prepared, the most stable being the tetraphenylphosphonium and tetraphenylarsonium derivatives. IR and NMR data are reported.

Complementary thin-layer chromatographic separations of some polyhedral borane anions and their derivatives

Anionic borane derivatives have been separated using ion-exchange and partition thin-layer chromatographic systems. The R F order of the borane compounds in the ion-exchange systems was approximately the inverse of that for the partition systems. Derivatives of B 10H 10 2− and B 12H 12 2− with similar substituents showed excellent separation, and there is evidence that these systems can resolve some geometrical isomers of disubstituted B 10H 10 2−.

Chemistry of boranes. XXVIII. New polyhedral borane anions, B8H82-, B8H8.-, and B7H72-

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of boranes. XXVIII. New polyhedral borane anions, B8H82-, B8H8.-, and B7H72-Frank Klanberg, Donald R. Eaton, Lloyd J. Guggenberger, and Earl L. MuettertiesCite this: Inorg. Chem. 1967, 6, 7, 1271–1281Publication Date (Print):July 1, 1967Publication History Published online1 May 2002Published inissue 1 July 1967https://doi.org/10.1021/ic50053a001RIGHTS & PERMISSIONSArticle Views442Altmetric-Citations115LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (1 MB) Get e-Alerts Get e-Alerts

Chemistry of Boranes. XXVII. New Polyhedral Borane Anions, B9H92- and B11H112-

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTChemistry of Boranes. XXVII. New Polyhedral Borane Anions, B9H92- and B11H112-F. Klanberg and E. L. MuettertiesCite this: Inorg. Chem. 1966, 5, 11, 1955–1960Publication Date (Print):November 1, 1966Publication History Published online1 May 2002Published inissue 1 November 1966https://doi.org/10.1021/ic50045a027RIGHTS & PERMISSIONSArticle Views439Altmetric-Citations91LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (771 KB) Get e-Alerts Get e-Alerts