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Crossed aldol reactions of the CF3-containing pseudo C2 symmetric cyclic imide 3 were carried out by way of the corresponding boron bisenolate to stereoselectively furnish the desired products 4 and this procedure allowed the preferential construction of the diastereomers of the compounds previously obtained from the acyclic counterpart 1. [ABSTRACT FROM AUTHOR]

A homogeneous series of well-defined butadiynylene-BODIPY oligomers containing up to four BODIPY moieties have been synthesized from a “one-pot” oxidative homocoupling reaction of 2,6-di((trimethylsilyl)ethynyl)BODIPY. Further derivation of the resultant BODIPY dimer generates a water-soluble, red-emitting butadiyne-linked BODIPY dimer with pyridinium ions, which can ratiometrically detect viscosity, based on the two fluorescent conformers with the two BODIPY cores twisted and planar to each other depending on the viscosity of the environment. [ABSTRACT FROM AUTHOR]

We present the selective atom economical synthesis of borasiloxanes using a multi-component approach directly by the one-pot ruthenium catalysed reaction of boranes, silanes and water. [ABSTRACT FROM AUTHOR]

Conjugated boron heterocycles have emerged as attractive synthetic targets due to their potential in medicinal chemistry and as electronic materials. However, the development of unsaturated boracycles has been hampered by difficulties in their preparation. Recently, a new synthetic avenue to access these species has been developed that takes advantage of the high reactivity of boroles. These five-membered anti-aromatic heterocycles can react with substrates to furnish ring expansion products via the insertion of one, two, or three atoms into the boracyclic ring. The ring expansion can occur via two pathways, the first exploits the activated diene moiety of the heterocycle in Diels–Alder chemistry with the resulting bicyclic species undergoing further rearrangements. The second reaction pathway is initiated by the coordination of the Lewis basic site of a substrate to the highly Lewis acidic boron center rendering the endocyclic B–C bond of the borole nucleophilic, inducing the formation of larger boracycles via attack at the electrophilic site of the substrate. This review summarizes the current state of this chemistry and details the mechanisms leading to the products. The methodologies described herein could very well be extended to other substrates, as well as applied to other anti-aromatic heterocycles. [ABSTRACT FROM AUTHOR]

The Ph2P-stabilized borenium 1 reacts cleanly with PhNH2, NH3 and HNTf2 to give a variety of boron compounds, namely the amino-substituted borenium 2 (substitution reaction at B), the neutral phosphine–borane 3, the mixed P/N-stabilized boronium 4 and the dicationic boron species 6. Remote modulation of the Lewis acidity at boron has been studied by preparing the related iPr2P-stabilized borenium 7 and reacting it with dihydrogen. [ABSTRACT FROM AUTHOR]

The thermal dehydrogenative coupling of aryl phosphine–borane adducts with iridium complexes bearing a bis(phosphinite) pincer ligand is reported. This catalysis produces high molecular weight poly(phosphinoboranes) [ArPH–BH2]n (Ar = Ph, pTol, Mes). Furthermore, we investigated the reactivity of these pincer complexes towards primary phosphines and their respective borane adducts on a stoichiometric scale. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of a photosensitizer containing boron-dipyrromethene and diarylethene. The photosensitizer has photo-controlled reversible photosensitivity and offers potential applications in photochemical catalysis and the degradation of organic pollutants. [ABSTRACT FROM AUTHOR]

Boronate affinity molecularly imprinted polymer inverse opal particles were developed for the multiplex label-free detection of glycoproteins with high sensitivity and specificity. [ABSTRACT FROM AUTHOR]

The synthesis and preliminary characterization of a boron-based 2D framework are presented. The peculiar electronic and morphological properties of this compound, together with its facile formation process, enable it to be used as a novel smart material for the design of electronic devices. [ABSTRACT FROM AUTHOR]

A stereoselective and electrocatalytic coupling reaction of isoeugenol has been reported for the first time in a 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)/boron-doped diamond (BDD) electrode system. This particular C–C bond formation and diastereoselectivity is driven by a solvate interaction between the radical species and another isoeugenol molecule. Due to an electrocatalytic cycle, only understoichiometric amounts of charge are necessary. Since electric current is directly employed as the oxidant, the reaction is metal and reagent-free. In addition, the electrolysis can be conducted in a very simple undivided beaker-type cell under constant current conditions. Therefore, the protocol is easy to use, suitable for scale-up, and inherently safe. [ABSTRACT FROM AUTHOR]

A new dual-boron-cored luminogen ligated with a nitrogen-containing multidentate ligand and four bulky phenyl rings was readily synthesized. The unique molecular structure endows this BN-containing luminogen with rich photophysical properties in either solution or in the solid state, including a large Stokes shift, aggregation induced emission activity and reversible piezochromism. Furthermore, this BN-containing luminogen exhibits good capabilities for imaging living cells and sensing of fluoride anions. [ABSTRACT FROM AUTHOR]

The frustrated Lewis pair comprised of B(C6F5)3 and a boryl–borate lithium salt Li[pinBB(Ph)pin] can efficiently activate dihydrogen, pinacolborane and ethylene at ambient temperature. Theoretical studies suggest that the nucleophilic sp2 boryl moiety of Li[pinBB(Ph)pin] plays different roles in these reactions. [ABSTRACT FROM AUTHOR]

This study is motivated by the recent discovery of the first all-boron fullerene analogue, a B40 cluster with D2d point-group symmetry, dubbed borospherene (Nat. Chem., 2014, 6, 727). Insight into the electronic structures and spectral properties of B40 is timely and important to understand the borospherene and the transition from open-ended plate or ribbon-like structures to a hollow-cage structure at B40. Optimized geometries of borospherene B40 for both the ground state and the first excited state allow us to compute spectral properties including UV-vis absorption, infrared (IR) and Raman spectra. Highly resolved absorption and emission spectra are obtained, for the first time, for the fullerene at the time-dependent density-functional theory (TD-DFT) level within the Franck–Condon approximation and including the Herzberg–Teller effect. Assigned vibrational modes in absorption and emission spectra are readily compared with future spectroscopy measurements to distinguish the hollow-cage structure of D2d-B40 from other quasi-planar boron structures. [ABSTRACT FROM AUTHOR]

This study is motivated by the recent discovery of the first all-boron fullerene analogue, a B40 cluster with D2d point-group symmetry, dubbed borospherene (Nat. Chem., 2014, 6, 727). Insight into the electronic structures and spectral properties of B40 is timely and important to understand the borospherene and the transition from open-ended plate or ribbon-like structures to a hollow-cage structure at B40. Optimized geometries of borospherene B40 for both the ground state and the first excited state allow us to compute spectral properties including UV-vis absorption, infrared (IR) and Raman spectra. Highly resolved absorption and emission spectra are obtained, for the first time, for the fullerene at the time-dependent density-functional theory (TD-DFT) level within the Franck–Condon approximation and including the Herzberg–Teller effect. Assigned vibrational modes in absorption and emission spectra are readily compared with future spectroscopy measurements to distinguish the hollow-cage structure of D2d-B40 from other quasi-planar boron structures. [ABSTRACT FROM AUTHOR]

A new domino strategy for selective synthesis of enaminones and their difluoroboron complexes through aryl migration has been developed. The reaction features low-cost and readily accessible starting materials, reliable scalability, and bond-forming efficiency as well as simple one-pot operation, which makes this strategy highly viable for future applications. [ABSTRACT FROM AUTHOR]

Heating a benzene solution of [η5-C2B9H10] Ta(NMe2)3 (1) in the presence of pyridine gave an unprecedented complex [η¹:η6-(Me2NCH2CH2)C2B9H10]Ta (NMe2)NC5H5(2). On the other hand, reaction of (η5-C2B9H11)TaMe3 with adamantly isonitrile (AdNC) in dimethoxyethane (DME) at room temperature afforded another unexpected complex (η6-C2B9H11)Ta[η³-C,C,N-CH2C(CH3)NAd](DME) (4). These results show that pyridine and DME are essential for the formation of 2 and 4, respectively. It is suggested that the n/do-η5-C2B9H10R2- ligand in tantallacarboranes takes up two electrons released by reductive elimination to form an arachno-η6-C2B9H10R4- fragment via the cage C-C bond cleavage. [ABSTRACT FROM AUTHOR]

Two-electron reduction of bis(carbene) boronium salts allows for the preparation of unsymmetrically substituted nucleophilic boron derivatives of type (L1)(L2)BH, which are characterized by X-ray crystallography. A single electron reduction of the same starting materials leads to the corresponding boron-centered radical cations (L1)(L2)BH.+, X--. [ABSTRACT FROM AUTHOR]

A novel triarylboron compound, MPB, exhibiting reversible thermochromic dual-fluorescence in solid-state polymers and in liquid solvents was designed and synthesized. The fluorescent solid-state polymer with MPB can serve as a highly sensitive self-reference temperature indicator with a concentration independent feature. [ABSTRACT FROM AUTHOR]

The synthesis of boron-pyridyl-imino-isoindoline dyes, a novel type of BODIPY analogue, involves a facile and scalable two-step reaction. Broad envelopes of intense vibrational bands are observed for the main spectral bands in the absorption and emission spectra. High fluorescence quantum yields are obtained in solution, with significant intensity also observed in the solid-state. [ABSTRACT FROM AUTHOR]

Boron complexes of [14]triphyrins(2.1.1) were prepared from free-base [14]triphyrins(2.1.1) with phenylboron dichloride. The absorption spectrum of the meso-free β-alkyl–triphyrin boron complex in CH2Cl2 showed a broad weak band at around 640 nm assigned to transition from B-phenyl to the triphyrin, while that of the meso-aryl benzotriphyrin boron complex showed only Soret and Q bands. [ABSTRACT FROM AUTHOR]

BODIPY derivatives with one or two benzene units fused at different positions are prepared using novel synthetic methods. The resulting dye 1 shows deep red fluorescence with a large Stokes shift. Dyes 2 and 3 are reported for the first time and 3 exhibits near infrared absorption. The impact of benzannulation at different positions of BODIPY is discussed, and the geometry and electronic structure are studied by DFT calculations. [ABSTRACT FROM AUTHOR]