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71.
Vincent J. Kalish Robert L. Shone Steven W. Kramer Paul W. Collins Kevin A. Babiak Kathleen T. McLaughlin 《合成通讯》2013,43(11):1641-1645
Hydrozirconation-iodination of a terminal acetylene followed by lithium-iodide exchange and finally dilithio cyanocuprate mediated conjugate addition to an appropriate cyclopentenone is reported as an efficient method for the synthesis of prostaglandin analogues. 相似文献
72.
Ashley J. Basson Dr. Nathan R. Halcovitch Dr. Mark G. McLaughlin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(48):e202201107
A range of highly functionalized polycyclic fragments have been synthesized, employing a catalytic dehydrative cyclization. A range of nucleophiles are shown to be successful, with the reaction producing numerous high value motifs. 相似文献
73.
Thomas H. Walter Bonnie A. Alden Kenneth Berthelette Jessica A. Field Nicole L. Lawrence Justin McLaughlin Amit V. Patel 《Journal of separation science》2022,45(8):1389-1399
We have characterized a sulfobetaine stationary phase based on 1.7 μm ethylene-bridged hybrid organic–inorganic particles, which is intended for use in hydrophilic interaction chromatography. The efficiency of a column packed with this material was determined as a function of flow rate, demonstrating a minimum reduced plate height of 2.4. The batch-to-batch reproducibility was assessed using the separation of a mixture of acids, bases, and neutrals. We compared the retention and selectivity of the hybrid sulfobetaine stationary phase to that of several benchmark materials. The hybrid sulfobetaine material gave strong retention for polar neutrals and high selectivity for methyl groups, hydroxy groups, and configurational isomers. Large differences in cation and anion retention were observed among the columns. We characterized the acid and base stability of the hybrid sulfobetaine stationary phase, using accelerated tests at pH 1.3 and 11.0, both at 70°C. The results support a recommended pH range of 2–10. We also investigated the performance of columns packed with this material for metal-sensitive analytes, comparing conventional stainless steel column hardware to hardware that incorporates hybrid surface technology to mitigate interactions with metal surfaces. Compared to the conventional columns, the hybrid surface technology columns showed a greatly improved peak shape. 相似文献
74.
Clear evidence for symplectic symmetry in low-lying states of 12C and 16O is reported. Eigenstates of 12C and 16O, determined within the framework of the no-core shell model using the J-matrix inverse scattering potential with A相似文献
75.
A method to track a grid of cardiac material points in three dimensions using slice-following (SF) tagged magnetic resonance imaging (MRI) and harmonic-phase MRI is presented. A three-dimensional grid of material points on the lines of intersections of short-axis (SA) and long-axis (LA) planes is automatically tracked by combining two-dimensional pathlines that are computed on both SA and LA image planes. This process yields the true three-dimensional motion of points originating on the image plane intersections. Experimental data from normal volunteers, each obtained in four short breath-holds using the SF harmonic phase MRI pulse sequence, is presented. A validation of two-dimensional in-plane tracks using this pulse sequence on a moving phantom is also presented. 相似文献
76.
77.
Laura L. Adduci Dr. Matthew P. McLaughlin Trandon A. Bender Dr. Jennifer J. Becker Prof. Dr. Michel R. Gagné 《Angewandte Chemie (International ed. in English)》2014,53(6):1646-1649
The conversion of readily available cellulosic biomass to valuable feedstocks and fuels is an attrative goal but a challenging transformation that requires the cleavage of multiple nonactivated C? O bonds. Herein, the Lewis acid trispentafluorophenylborane (B(C6F5)3) is shown to catalyze the metal‐free hydrosilylative reduction of monosaccharides and polysaccharides to give hydrocarbons with reduced oxygen content. The choice of the silane reductant influences the degree of deoxygenation, with diethylsilane effecting the complete reduction to produce hexanes while tertiary silanes give partially deoxygenated tetraol and triol products. 相似文献
78.
Durgesh V. Wagle Steven P. Kelley Gary A. Baker Kanishka Sikligar Jerry L. Atwood 《Angewandte Chemie (International ed. in English)》2020,59(21):8062-8065
A hexameric metal–organic nanocapsule is assembled from pyrogallol[4]arene units, which are stitched together with indium ions. This indium‐seamed capsule is the first instance of a M24L6 type hexameric coordination cage held together exclusively by trivalent metal ions. Explicitly, unlike previously reported pyrogallol[4]arene‐based metal‐seamed capsules, the current In3+ seamed capsule is entirely supported by O→In coordinate bonds. This work demonstrates the important proof of concept of the ability of pyrogallol[4]arene to react with metals in higher oxidation states to assemble into atomically‐precise hexameric coordination cages. As such, these results open up exciting avenues toward the assembly of previously unanticipated metal–organic capsules, for example offering inspiration for tackling metals exhibiting high valence states such as in the lanthanide and actinide series. 相似文献
79.
Robert C. Morrison Jerry R. Mizell Orville W. Day 《International journal of quantum chemistry》1996,57(3):355-360
Generalized overlap amplitudes (GOAS) are calculated between the lithium atom and several states of Li+. An examination of the long-range behavior of the GOAS indicates that they are coupled, appearing to have the same exponential decay at large r. At intermediate distances from the nucleus, the GOAS decay with their unique exponential rate and the decay rates only merge at large r. Although many of the GOAS appear to be similar, their distinctness indicates that they may, in fact, be linearly independent. © 1996 John Wiley & Sons, Inc. 相似文献
80.