Single-Site Cobalt Catalysts at New Zr<sub>8</sub>(μ<sub>2</sub>-O)<sub>8</sub>(μ<sub>2</sub>-OH)<sub>4</sub> Metal-Organic Framework Nodes for Highly Active Hydrogenation of Alkenes, Imines, Carbonyls, and Heterocycles
作者:Pengfei Ji、Kuntal Manna、Zekai Lin、Ania Urban、Francis X. Greene、Guangxu Lan、Wenbin Lin
DOI:10.1021/jacs.6b06759
日期:2016.9.21
We report here the synthesis of robust and porous metal-organic frameworks (MOFs), M-MTBC (M = Zr or Hf), constructed from the tetrahedral linker methane-tetrakis(p-biphenylcarboxylate) (MTBC) and two types of secondary building units (SBUs): cubic M8(μ2-O)8(μ2-OH)4 and octahedral M6(μ3-O)4(μ3-OH)4. While the M6-SBU is isostructural with the 12-connected octahedral SBUs of UiO-type MOFs, the M8-SBU
STABILIZATION OF ACTIVE METAL CATALYSTS AT METAL-ORGANIC FRAMEWORK NODES FOR HIGHLY EFFICIENT ORGANIC TRANSFORMATIONS
申请人:The University of Chicago
公开号:US20180361370A1
公开(公告)日:2018-12-20
Metal-organic framework (MOFs) compositions based on post¬synthetic metalation of secondary building unit (SBU) terminal or bridging OH or OH
2
groups with metal precursors or other post-synthetic manipulations are described. The MOFs provide a versatile family of recyclable and reusable single-site solid catalysts for catalyzing a variety of asymmetric organic transformations, including the regioselective boryiation and siiylation of benzyiic C—H bonds, the hydrogenation of aikenes, imines, carbonyls, nitroarenes, and heterocycles, hydroboration, hydrophosphination, and cyclization reactions. The solid catalysts can also be integrated into a flow reactor or a supercritical fluid reactor.
found to be B(C(6)F(5))(3) > BEt(3) ≈ BH(3)·THF > BPh(3) ≫ BF(3)·OEt(2) > B(OMe)(3) ≫ BCl(3). The stability of the catalytic systems was checked via TON vs time plots, which revealed the boron Lewis acids to cause an approximate inverse order with the Lewis acid strength: BPh(3) > BEt(3) ≈ BH(3)·THF > B(C(6)F(5))(3). For the 2a/BPh(3) system a maximum TON of 3.1 × 10(4) and for the 2a/B(C(6)F(5))(3) system
二溴亚硝酰基(二氢)铼(I)络合物 [ReBr(2)(NO)(PR(3))(2)(η(2)-H(2))] (1; R = iPr, a; Cy, b ) 和 Me(2)NH·BH(3) (DMAB) 在 90 °C 或环境温度和 10 bar H(2) 下催化各种末端和环状烯烃(1-己烯、1-辛烯、环辛烯)的氢化、苯乙烯、1,5-环辛二烯、1,7-辛二烯、α-甲基苯乙烯)。在 1-己烯的氢化中实现了 3.6 × 10(4) h(-1) 在 90 °C 和 1.7 × 10(4) h(-1) 在 23 °C 的最大转换频率 (TOF) 值。1/DMAB 系统非凡的催化性能归因于五配位铼 (I) 氢化物复合物 [Re(Br)(H)(NO)(PR(3))(2)] (2; R = iPr, a; Cy, b) 和源自 DMAB 的路易斯酸 BH(3) 的作用。相关的 2/BH(3)·THF 催化体
Bis(imino)pyridine Cobalt-Catalyzed Dehydrogenative Silylation of Alkenes: Scope, Mechanism, and Origins of Selective Allylsilane Formation
作者:Crisita Carmen Hojilla Atienza、Tianning Diao、Keith J. Weller、Susan A. Nye、Kenrick M. Lewis、Johannes G. P. Delis、Julie L. Boyer、Aroop K. Roy、Paul J. Chirik
DOI:10.1021/ja5060884
日期:2014.8.27
aryl-substituted bis(imino)pyridine cobalt methyl complex, ((Mes)PDI)CoCH3 ((Mes)PDI = 2,6-(2,4,6-Me3C6H2-N═CMe)2C5H3N), promotes the catalytic dehydrogenativesilylation of linear α-olefins to selectively form the corresponding allylsilanes with commercially relevant tertiary silanes such as (Me3SiO)2MeSiH and (EtO)3SiH. Dehydrogenativesilylation of internal olefins such as cis- and trans-4-octene
Decamethyltitanocene hydride intermediates in the hydrogenation of the corresponding titanocene-(η<sup>2</sup>-ethene) or (η<sup>2</sup>-alkyne) complexes and the effects of bulkier auxiliary ligands
reactions of titanocene [Cp*2Ti] (Cp* = η5-C5Me5) and its derivatives [Cp*(η5:η1-C5Me4CH2)TiMe] and [Cp*2Ti(η2-CH2=CH2)] with excess dihydrogen at room temperature and pressures lower than 1 bar revealed the formation of dihydride [Cp*2TiH2] (1) and the concurrent liberation of either methane or ethane, depending on the organometallic reactant. The subsequent slow decay of 1 yielding [Cp*2TiH] (2) was mediated