5980-97-2Relevant articles and documents
Magnesium promoted autocatalytic dehydrogenation of amine borane complexes: A reliable, non-cryogenic, scalable access to boronic acids
Marciasini, Ludovic D.,Richard, Jimmy,Cacciuttolo, Bastien,Sartori, Guillaume,Birepinte, Melodie,Chabaud, Laurent,Pinet, Sandra,Pucheault, Mathieu
, p. 164 - 171 (2018/12/05)
Owing to the unusual reactivity of dialkylamine-borane complexes, a methodology was developed to simply access boronic acids. The intrinsic instability of magnesium aminoborohydride was tweaked into a tandem dehydrogenation borylation sequence. Proceeding via an autocatalytic cycle, amineborane dehydrogenation was induced by a variety of Grignard reagents. Overall, addition of the organomagnesium species onto specially designed dialkylamine-borane complexes led to a variety of boronic acids in high yields. In addition, the reaction can be performed under Barbier conditions, on a large scale.
The Photostability of Two Optical Materials Based on Perylene Diimide Substituted by Different Aromatic Groups at the Bay Area
He, Junjie,Li, Song,Zeng, Heping
, p. 2800 - 2807 (2017/09/26)
The perylene diimide substituented by thiophene rings at bay area shows photoactivity and can be used as a photo sensor, but another one substituented by mestylene groups is photostable. The single crystal of 1,7-mesitylene perylene diimide was obtained. X-ray diffraction data of the crystal revealed that the plane of the perylene core was hardly twisted by introduction of mesitylene groups. These mestylene groups are like clips maintaining the planarity of the perylene core. Density functional theory calculation was applied to study the difference of photophysical and photochemical properties. The discovery is valuable for design guidance of perylene diimides.
Correlating electronic and catalytic properties of frustrated Lewis pairs for imine hydrogenation
Dorkó, éva,Kótai, Bianka,F?ldes, Tamás,Gy?m?re, ádám,Pápai, Imre,Soós, Tibor
supporting information, p. 258 - 262 (2017/09/12)
Combined computational and experimental work to probe Lewis acidity of some boranes to be used in FLP hydrogenation. Gutmann-Beckett method of estimating Lewis acidity has limited capacity for sterically congested boranes. Calculated hydride affinity is a more appropriate tool for gauging Lewis acidity and correlate their FLP hydrogenation utility.
Synthesis of substituted azulenes via Pt(II)-Catalyzed ring-expanding cycloisomerization
Usui, Kazuteru,Tanoue, Kensuke,Yamamoto, Kosuke,Shimizu, Takashi,Suemune, Hiroshi
, p. 4662 - 4665 (2015/01/16)
Substituted azulenes, valuable structures for electronic devices and pharmaceuticals, have been synthesized by the platinum(II)-catalyzed intramolecular ring-expanding cycloisomerization of 1-en-3-yne with ortho-disubstituted benzene. This novel method provides an alternative route for the efficient synthesis of substituted azulenes. The reaction mechanism of selected catalytic transformations was explored using density functional calculations.
Highly efficient one-pot access to functionalized arylboronic acids via noncryogenic bromine/magnesium exchanges
Leermann, Timo,Leroux, Frederic R.,Colobert, Francoise
supporting information; experimental part, p. 4479 - 4481 (2011/10/09)
A general and convenient protocol for the electrophilic borylation of aryl Grignard reagents prepared from arylbromides by direct insertion of magnesium in the presence of LiCl or by Mg/Br exchange with iPrMgCl?LiCl has been developed. Various aryl boronic acids were synthesized in a straightforward manner in excellent yields at 0 °C.
ASYMMETRIC-SYNTHESIS CATALYST BASED ON CHIRAL BROENSTED ACID AND METHOD OF ASYMMETRIC SYNTHESIS WITH THE CATALYST
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Page/Page column 19, (2010/11/08)
A compound usable as an asymmetric synthesis catalyst which can be easily synthesized without using any metal such as a lanthanoid group element; a method of asymmetric synthesis with the compound; and a chiral compound obtained by the asymmetric synthesis method. A Broensted acid is used as a catalyst in asymmetric synthesis, the chiral Broensted acid being represented by formula (1) below or formula (3) below. The asymmetric synthesis method employs the catalyst. Asymmetric synthesis with the catalyst gives a chiral compound.
Novel synthesis of arylboronic acids by electroreduction of aromatic halides in the presence of trialkyl borates
Laza, Carine,Dunach, Elisabet,Serein-Spirau, Francoise,Moreau, Joel J. E.,Vellutini, Luc
, p. 373 - 375 (2007/10/03)
A novel preparation of aryl and heteroarylboronic acids by an electrochemical coupling reaction is described. It is based on the reductive coupling between aromatic or heteroaromatic halides and a trialkyl borate. The reactions are carried out in DMF or THF with the use of sacrificial aluminium or magnesium anodes in a single-compartment cell. Arylboronic acids are obtained with moderate to good selectivities and isolated yields.
Formal total synthesis of (+)-diepoxin σ
Wipf, Peter,Jung, Jae-Kyu
, p. 6319 - 6337 (2007/10/03)
The highly oxygenated antifungal anticancer natural product (±)-diepoxin σ was prepared in 10 steps and in 15% overall yield from O-methylnaphthazarin. Highlights of the synthetic work include an Ullmann coupling and a possibly biomimetic oxidative spirocyclization for the introduction of the naphthalene ketal as well as the use of a retro-Diels-Alder reaction to unmask the reactive enone moiety in the naphthoquinone bisepoxide ring system. A novel highly bulky chiral binaphthol ligand was developed for a boron-mediated Diels-Alder reaction that constitutes a formal asymmetric total synthesis of (+)-diepoxin σ.
Sterically Hindered Organotin Compounds. Part 3. The Reaction Between Di-tert-butyltin Oxide and Organoboronic Acids
Brown, Paul,Mahon, Mary F.,Molloy, Kieran C.
, p. 3503 - 3510 (2007/10/02)
The reaction between (But2SnO)3 and BR(OH)2 has been investigated and found to yield two classes of product.The first is a boron-rich species, cyclo-But2SnO(RBO)2, which exists alongside its acyclic hydrolysis product SnBut22.The second product, which is tin-rich, SnBut2(OH)2t2SnO)2OBR>2, can be formulated as cyclo-RBO(But2SnO)2 chelated across one Sn-O-Sn unit by a molecule of SnBut2(OH)2.The crystal and molecular structures of SnBut22 and SnBut2(OH)2t2SnO)2OBC6H2Me3-2,4,6>2*2MeCN have been determined.
Reaction of Arylboronic Acids and their Derivatives with Lead Tetra-acetate. The Generation of Aryl-lead Triacetates, and meta- and para-Phenylenebis(lead triacetate), in situ for Electrophilic Arylation
Morgan, Jacqueline,Pinhey, John T.
, p. 715 - 720 (2007/10/02)
Arylboronic acids and some of their derivatives have been found to undergo a rapid boron-lead exchange with lead tetra-acetate.In the presence of a catalytic amount of mercury(II) acetate, the reaction produces mainly the aryl-lead triacetate, and it has been developed as a convenient method for in situ generation of these useful electrophilic C-arylating reagents.The reaction allows the generation for the first time of meta- and para-phenylenebis(lead triacetate), compounds which behave as meta- and para-phenylene dication equivalents.
