68 research outputs found

    A Potassium Diboryllithate: Synthesis, Bonding Properties, and the Deprotonation of Benzene

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    A potassium diboryllithate (B2LiK) was synthesized and structurally characterized. DFT calculations, including NPA and AIM analyses of B2LiK, revealed ionic interactions between the two bridging boryl anions and Li+ and K+. Upon standing in benzene, B2LiK deprotonated the solvent to form a hydroborane and a phenylborane. On the basis of DFT calculations, a detailed reaction mechanism, involving deprotonation and hydride/phenyl exchange processes, is proposed. An NBO analysis of the transition state for the deprotonation of benzene suggests that the deprotonation should be induced by the coordination of benzene to the K+.A â LiK â of work: A potassium diboryllithate, B2LiK, was synthesized and structurally characterized. The bonding situation in this compound was examined by NMR, XRD, NPA, and AIM analyses. B2LiK is able to deprotonate benzene with concomitant formation of phenylborane as the major product. A detailed reaction mechanism based on DFT calculations suggests that the deprotonation of benzene should be initiated by a transition state involving the coordination of benzene to K+.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137264/1/anie201605005_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137264/2/anie201605005-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137264/3/anie201605005.pd

    Prism-C2nC_2n carbon dimer, trimer, and nano-sheets: a quantum chemical study

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    Quantum chemical calculations have predicted the existence of a new carbon family with double-layered structures formed by arranging prism-C2n (n = 6, 8, and 12) units. Theoretical explorations of potential energy surfaces suggest the lowest barriers of the reaction channels to be ca. 30 kJ mol−1 for a D2h prism-C16 dimer and a D3h prism-C24 trimer. Geometry optimizations under periodic boundary conditions yield some prism-C2n sheets composed of CC single bonds of ca. 0.15–0.16 nm. The relative energies per one atom with respect to graphene are 90–160 kJ mol−1. Van der Waals thickness is estimated to be ca. 0.5 nm

    A prism carbon molecule C20_20

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    A new carbon family with a prism structure has been found by quantum chemical calculations. The prism-C20C_20 has a D10hD_10h structure with double-layered decagonal rings connected each other by ten vertical CC bonds. The CC bond lengths are 0.144 nm on the decagonal rings and 0.148 nm on the side faces. The diameter of the ring is 0.465 nm. The prismC20prism-C_20 is expected to be stable, since the lowest energy barrier from it was estimated to be 158.0 kJ mol1^−1
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