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Phosphine boran

Anne Harrison-Marchand, Jie Guang, Romain Duwald, Jacques Maddaluno, Hassan Oulyadi, Sami Lakhdar, Annie-Claude Gaumont
The synthesis and identification of unprecedented gem-dianionic phosphorus compounds, i.e. gem-dilithium phosphido-boranes Li2[RP*BH3], with R = Ph or Cy, are reported in THF solution. Those are obtained by double deprotonation of the corresponding primary phosphine-borane precursors RPH2*BH3. Their in-depth structural study, based on multinuclear (1H, 6Li, 7Li, 11B, 13C, 31P) mono- and bi-dimensional NMR analyses, indicates a strong influence of the phosphorus substituent on the structure of the gem-dianionic phosphorus structure: while a monomeric arrangement is obtained when R = phenyl, a cyclic oligomer is observed for R = cyclohexyl...
March 13, 2018: Chemistry: a European Journal
Nan Ding, Junqi Xu, Qi Zhang, Jianwei Su, Yu Gao, Xing Zhou, Tianyou Zhai
The p-n junction is one important and fundamental building block of the optoelectronic age. However, electrons and holes will be severely scattered in heterostructures led by the grain boundary at the alloy interface between two dissimilar semiconductors. In this work, we present BP nanowires with artificially controllable carrier type for the fabrication of homojunctions via adjusting borane/phosphine ratio during the deposition process, both prove high crystallization with fewer impurities. The homojunctions that constitute of n-type and p-type BP nanowires show apparent photovoltaic effect (EQE ≈ 10% under a ~0...
March 5, 2018: ACS Applied Materials & Interfaces
Nathan T Coles, Ruth L Webster
Catalytic dehydrocoupling methodologies, whereby dihydrogen is released from a substrate (or intermolecularly from two substrates) is a mild and efficient method to construct main group element-main group element bonds, the products of which can be used in advanced materials, and also for the development of hydrogen storage materials. With growing interest in the potential of compounds such as ammonia-borane to act as hydrogen storage materials which contain a high weight% of H2 , along with the current heightened interest in base metal catalyzed processes, this review covers recent developments in amine and phosphine dehydrocoupling catalyzed by iron complexes...
December 2017: Israel Journal of Chemistry
Robert Langer, Lisa Vondung, Lukas Alig, Monika Ballmann
Easy to prepare η²-coordinated phosphine-borane ligands are demonstrated to liberate hydrogen upon treatment with different σ-donor/π-acceptor ligands (CO, tBuNC, CN-). Depending on the utilized ancillary ligand different reaction pathways are observed, ranging from simple hydride protonation to iron-boron-bond formation and subsequent rearrangement to pincer-type ligands, which are based on a tri-coordinate boron centre. The latter reactivity is in line with a formal Umpolung at boron centre from a Lewis-acidic borane to a Lewis-basic boron-based donor ligand...
February 1, 2018: Chemistry: a European Journal
Wei Meng, Xiangqing Feng, Haifeng Du
The use of frustrated Lewis pairs is an extremely important approach to metal-free hydrogenations. In contrast to the rapid growth of catalytic reactions, asymmetric hydrogenations are far less developed due to a severe shortage of readily available chiral frustrated Lewis pair catalysts with high catalytic activities and selectivities. Unlike the stable Lewis base component of frustrated Lewis pairs, the moisture-sensitive boron Lewis acid component is difficult to prepare. The development of convenient methods for the quick construction of chiral boron Lewis acids is therefore of great interest...
December 15, 2017: Accounts of Chemical Research
Mio Matsumura, Mizuki Yamada, Atsuya Muranaka, Misae Kanai, Naoki Kakusawa, Daisuke Hashizume, Masanobu Uchiyama, Shuji Yasuike
The parent benzophospholo[3,2- b ]indole was prepared by the reaction of dichlorophenylphosphine with a dilithium intermediate, which was prepared in two steps from 2-ethynyl- N , N -dimethylaniline. Using the obtained benzophosphole-fused indole as a common starting material, simple modifications were carried out at the phosphorus center of the phosphole, synthesizing various functionalized analogs. The X-ray structure analysis of trivalent phosphole and phosphine oxide showed that the fused tetracyclic moieties are planar...
2017: Beilstein Journal of Organic Chemistry
Goki Hirata, Hideaki Satomura, Hidenobu Kumagae, Aika Shimizu, Gen Onodera, Masanari Kimura
The direct electrophilic, nucleophilic, and amphiphilic allylations of allylic alcohol by use of a palladium catalyst and organometallic reagents such as organoborane and organozinc has been developed. The phosphine-borane compound works as the effective ligand for palladium-catalyzed direct allylic amination of allylic alcohol. Thus, with secondary amines, the reaction was completed in only 1 h, even at room temperature.
November 17, 2017: Organic Letters
Pauline Minois, Jérôme Bayardon, Rita Meunier-Prest, Sylvain Jugé
A new method to link amino acid and peptide derivatives to [60]fullerene is described. It uses hydrophosphination with a secondary phosphine borane. First, the stereoselective synthesis of secondary phosphine borane amino acid derivatives was achieved by alkylation of phenylphosphine borane with γ-iodo-α-amino ester reagents under phase-transfer catalysis (PTC). Second, a sec-phosphine borane amino ester was saponified and coupled with α,γ-diamino esters to afford the corresponding dipeptide derivatives in good yields...
October 12, 2017: Journal of Organic Chemistry
Christopher M Bateman, Lev N Zakharov, Eric R Abbey
The title compound, C19H17BF3P {alternative name: triphen-yl[(tri-fluoro-boran-yl)meth-yl]phosphanium}, was formed by the reaction of tri-phenyl-phosphine with potassium iodo-methyl-tri-fluoro-borate. The mol-ecule features a nearly staggered conformation along the P-C bond and a less than staggered conformation along the C-B bond. In the crystal, weak C-H⋯F hydrogen bonds between the meta-phenyl C-H groups and the tri-fluoro-borate B-F groups form chains of R2(2)(16) rings along [100]. These chains are are further stabilized by weak C-H⋯π inter-actions...
July 1, 2017: Acta Crystallographica. Section E, Crystallographic Communications
Shao-Zhen Nie, Zhong-Yang Zhou, Ji-Ping Wang, Hui Yan, Jing-Hong Wen, Jing-Jing Ye, Yun-Yao Cui, Chang-Qiu Zhao
The secondary RP-(-)-menthyl alkylphosphine oxide was confirmed as configurationally stable toward base and was used in base-promoted alkylation, stereospecifically affording P-retained bis or functional tertiary phosphine oxides in excellent yields. The alkylated products were deoxygenated using oxalyl chloride followed by ZnCl2-NaBH4 to form P-inversed bidentate phosphine boranes in high stereoselectivities.
August 30, 2017: Journal of Organic Chemistry
Michele Soleilhavoup, Guy Bertrand
Free borylenes (R-B:) have only been spectroscopically characterized in the gas phase or in matrices at very low temperatures. However, in recent years, a few mono- and bis(Lewis base)-stabilized borylenes have been isolated. In both of these compounds the boron atom is in the formal oxidation state +I which contrasts with classical organoboron derivatives wherein the element is in the +III oxidation state. Mono(Lewis base)-stabilized borylenes are isoelectronic with singlet carbenes, and their reactivity mimics to some extent that of transition metals...
August 21, 2017: Angewandte Chemie
Micheal Gediga, Christoph M Feil, Simon H Schlindwein, Johannes Bender, Martin Nieger, Dietrich Gudat
A neutral N-heterocyclic phosphenium complex of manganese was synthesised by a metathesis approach and characterised by IR, NMR, and XRD studies. The short P-Mn distance suggests a substantial metal-ligand double bond character. Reaction with a hydride produced an anionic phosphine complex, which was also characterised by IR and NMR spectroscopy and, after anion exchange, a single-crystal XRD study. Protonation of the anion occurs at the metal to yield a neutral phosphine metal carbonyl hydride, which releases dihydrogen upon irradiation with UV light...
May 30, 2017: Chemistry: a European Journal
David A Janus, Christopher J Lieven, Megan E Crowe, Leonard A Levin
Phosphine-borane complexes are recently developed redox-active drugs that are neuroprotective in models of optic nerve injury and radioprotective in endothelial cells. However, a single dose of these compounds is short-lived, necessitating the development of sustained-release formulations of these novel molecules. We screened a library of biodegradable co- and non-block polyester polymer systems for release of incorporated phosphine-borane complexes to evaluate them as drug delivery systems for use in chronic disease...
June 9, 2017: Pharmaceutical Development and Technology
A Telleria, P W N M van Leeuwen, Z Freixa
Eight new ruthenium(ii) half-sandwich complexes containing azobenzene-appended pyridine (1), bipyridine (2-5) and phosphine (6 and 7) ligands have been synthesized and fully characterized. UV-vis spectroscopic studies showed that the trans-to-cis photoisomerization was strongly inhibited upon coordination to the metal centre in azopyridine-derived ligands 1 and 2, but it remained efficient in azobenzene-appended bipyridine (3-5) and phosphine (6 and 7) ligands. The complexes were tested as precatalysts for photo-controlled hydrogen generation by hydrolytic decomposition of ammonia-borane (AB)...
March 14, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
Kevin Rousée, Xavier Pannecoucke, Annie-Claude Gaumont, Jean-François Lohier, Fabrice Morlet-Savary, Jacques Lalevée, Jean-Philippe Bouillon, Samuel Couve-Bonnaire, Sami Lakhdar
This work describes the first transition metal-free stereospecific synthesis of (E)-(1-fluoro-2-arylvinyl)phosphine boranes through the addition of diarylphosphine-boranes to gem-bromofluoroalkenes in the presence of a base at room temperature. The reaction proceeds well under very mild conditions and tolerates a variety of functionalities. Scope and limitations of the reaction are discussed. Mechanistic investigations have been undertaken and revealed that the reaction takes place through an SRN1 mechanism...
January 27, 2017: Chemical Communications: Chem Comm
Giovanni Bistoni, Alexander A Auer, Frank Neese
The interaction of Lewis acids and bases in both classical Lewis adducts and frustrated Lewis pairs (FLPs) is investigated to elucidate the role that London dispersion plays in different situations. The analysis comprises 14 different adducts between tris(pentafluorophenyl)borane and a series of phosphines, carbenes, and amines with various substituents, differing in both steric and electronic properties. The domain-based local pair natural orbital coupled-cluster (DLPNO-CCSD(T)) method is used in conjunction with the recently introduced local energy decomposition (LED) analysis to obtain state-of-the-art dissociation energies and, at the same time, a clear-cut definition of the London dispersion component of the interaction, with the ultimate goal of aiding in the development of designing principles for acid/base pairs with well-defined bonding features and reactivity...
November 3, 2016: Chemistry: a European Journal
Merle Arrowsmith, Dominic Auerhammer, Rüdiger Bertermann, Holger Braunschweig, Gerhard Bringmann, Mehmet Ali Celik, Rian D Dewhurst, Maik Finze, Matthias Grüne, Michael Hailmann, Thomas Hertle, Ivo Krummenacher
Reduction of carbene-borane adduct [(cAAC)BBr2 (CN)] (cAAC=1-(2,6-diisopropylphenyl)-3,3,5,5-tetramethylpyrrolidin-2-ylidene) cleanly yielded the tetra(cyanoborylene) species [(cAAC)B(CN)]4 presenting a 12-membered (BCN)4 ring. The analysis of the Kohn-Sham molecular orbitals showed significant borylene character of the B(I) atoms. [(cAAC)B(CN)]4 was found to reduce two equivalents of AgCN per boron center to yield [(cAAC)B(CN)3 ] and fragmented into two-coordinate boron(I) units upon reaction with IMeMe (1,3,4,5-tetramethylimidazol-2-ylidene) to yield the corresponding tricoordinate mixed cAAC-NHC cyanoborylene...
October 12, 2016: Angewandte Chemie
Paul A Sibbald
Phosphine-borane adducts are a well-known moiety in synthetic and coordination chemistry. These complexes form a dative bond in which the Lewis basic phosphorus atom donates electron density into an empty p-orbital of the Lewis acidic boron atom. However, donation of the phosphorus lone pair is not the only stabilizing interaction, as hyperconjugation and electrostatic interaction also play important roles in bonding. This paper describes a detailed density functional theory level (B3LYP) study completed to determine the impact electron-donating and withdrawing substituents have on phosphine-borane bonds through the investigation of a series of para-substituted PAr3-BH3 and PH3-BAr3 phosphine-borane adducts...
November 2016: Journal of Molecular Modeling
Matthew J Chalkley, Jonas C Peters
Given the importance of Fe-NO complexes in both human biology and the global nitrogen cycle, there has been interest in understanding their diverse electronic structures. Herein a redox series of isolable iron nitrosyl complexes stabilized by a tris(phosphine)borane (TPB) ligand is described. These structurally characterized iron nitrosyl complexes reside in the following highly reduced Enemark-Feltham numbers: {FeNO}(8) , {FeNO}(9) , and {FeNO}(10) . These {FeNO}(8-10) compounds are each low-spin, and feature linear yet strongly activated nitric oxide ligands...
September 19, 2016: Angewandte Chemie
Tsuneo Imamoto
In this account, the design, synthesis, and application of P-chirogenic phosphine ligands that have been mainly carried out in our laboratory over the last three decades are described. Various enantiopure P-chirogenic phosphine ligands have been efficiently prepared by using phosphine boranes as intermediates. Conformationally rigid and electron-rich P-chirogenic phosphine ligands possessing C2 symmetry as well as a bulky alkyl group and a small group at the phosphorus atoms exhibit excellent enantioselectivities and catalytic efficiency in a variety of transition-metal-catalyzed asymmetric reactions...
December 2016: Chemical Record: An Official Publication of the Chemical Society of Japan ... [et Al.]
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