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Showing 1 to 15 of 15 for “"diboron"”.
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The development and applications of unsymmetrical diboron compounds
… of the previous examples employed symmetrical diboron reagents such as B₂(pin)₂ (pin = pinacolate) and B₂(cat)₂ (cat = catecholate). There are, however, limited examples of boration using unsymmetrical diboron reagents. This dissertation discloses two transition metal-catalyzed borations of …
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Development of Transition Metal-Catalyzed Borylation Protocols using Symmetrical and Unsymmetrical Diboron Reagents
… borylation protocols with alkynes and diboron reagents. An open-to-air copper(II)-catalyzed aqueous borylation protocol of alkynoates and a symmetrical diboron reagent is reported. Conjugate addition of the boryl-copper species to the electrophilic β-carbon provided …
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Activation of diboron reagents: The development of mild conditions for the synthesis of unique organoboron compounds
… using transition metal-catalyzed reactions of diboron reagents. A unique "mixed" diboron reagent was developed (PDIPA diboron) that contains sp2- and sp3-hybridized boron atoms, unambiguously confirmed by X-ray crystallography. PDIPA diboron is sufficiently activated internally through a …
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Development of Methods for Boron Reagents
… intermediates. It has also been shown that diboron reagents can act as reaction mediators due to the unique properties of the boron atom. To that end, this dissertation discloses three novel methods of employing boron reagents. Chapter 1 describes a method of utilizing a diboron reagent …
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Synthetic and catalytic studies of Group 11 N-heterocyclic carbene complexes
… of the borate complex with the bis(pinacolato)diboron, (pin)B-B(pin), giving the stable byproduct (pin)B-O-B(pin). The use of a copper(I) alkoxide precatalyst and stoichiometric diboron reagent results in catalytic reduction of CO2, with high turnover numbers (1000 per Cu) and frequencies (100 …
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Boron-Mediated Semireduction of Alkynoic Acid Derivatives
… dissertation describes three novel uses of a diboron reagent or pinacolborane that reduce propiolic acid derivates selectively to (E)-alkenes and one method that installs pinacolatoboron yielding exclusively (E)-β-borylacrylamides. We investigated the trans-selective hydroboration of primary …
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Development of Novel, Regioselective Borylation Protocols
… involving substrate-mediated activation of a diboron reagent. This dissertation describes the author's contributions to the development of both a transition metal-catalyzed diboration and a transition metal-free protoboration. A transition metal-free diboration of alkynamides is described in …
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Selective Borylations of Carbon-Carbon pi-Bonds
… This dissertation describes the use of a diboron reagent to install boron on the electron withdrawing allenoate scaffold as well as on disubstituted 1,3-diynes. Lastly, this dissertation will cover the preliminary anti-fungal activity of a novel oxaborole scaffold. We investigated the …
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Iridium-catalyzed borylation of aromatic and aliphatic C-H bonds: methodology and mechanism
… boron reagents besides the common bis(piacolato)diboron were studied in the C-H borylation of arenes. A different diboron reagent, bis(hexyleneglycol)diboron, reacts with arenes to form arylboronate esters in good yields. The borylation of secondary C-H bonds, specifically secondary C-H bonds of …
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Nickel-catalyzed cross-coupling reactions involving secondary and tertiary alkyl nucleophiles
… of primary alkyl halides using bis(pinacolato)diboron as the boron source has been reported. This reaction is very general and can accommodate a wide range of functional groups. To increase the utility of this process, the crude borylation product has been converted into the corresponding …
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Regio- and Stereo- selective Methods for the Borylation of Substituted Alkynes
… of tri-n-butylphosphie and the unsymmetric diboron reagent pinBBdan, 1-boryl-1,3-enyne products were generated in up to 63% and >99:1 (Z)-selectivity. These 1,8-diaminonaphthalene products can be converted to the corresponding pinacolboranes or trifluoroborate salts. They also demonstrated …
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Metal-Catalyzed Formation and Transformations of Carbon-Boron Bonds
… allenes with a differentially protected diboron reagent, pinB-Bdan. The reaction proceeds regioselectively in high yields to furnish olefins bearing a vinylic Bpin and an allylic Bdan moiety. The subsequent chemoselective transformation of each boron center was demonstrated. Methods for …
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BIFUNCTIONAL BF2 COMPLEXES OF POLYDENTATE BIS(AMIDINATES): SYNTHESIS, STRUCTURES, AND PHOTOLUMINESCENCE PROPERTIES
… and elemental analysis. For all four diboron-bis(amidinate) complexes, the molecular structures are presented. The photoluminescent properties of <strong>L<sup>1-4</sup></strong>(BF<sub>2</sub>)<sub>2</sub> were investigated by their excitation, and emission spectra, as well as quantum …
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I. Reaction mining—a next-generation platform for reaction discovery II. Rapid, anhydrous, homogenous Suzuki-Miyaura cross-coupling of aryl and alkylboronates
… commercially available bis(neopentylglycolato)diboron is described. The TMSOK-promoted cross-coupling conditions reported by Denmark were found to be also applicable to alkylboronic esters, facilitating the discovery of a rapid B-alkyl Suzuki-Miyaura cross-coupling of primary alkylboronic …
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Synthetic Studies Towards the Crisamicins
… steps from vanillin 1.271) using bis(pinacolato)diboron 1.179. This coupling method successfully afforded binaphthyls 2.8b and 2.8d which were subjected to attempts to effect either double bromination, double acetylation or double Fries rearrangement to a more functionalised biaryl system. …