The reaction of ortho-substituted aromatic azides with boron trichloride or trifluoride
作者:Piero Spagnolo、Paolo Zanirato
DOI:10.1039/p19880002615
日期:——
The reaction of borontrichloride or trifuoride with ortho-aryl, -diazoaryl, and -arylazoaryl phenyl azides in benzene at room temperature generally gives fused azoles in high yields. Treatment of 2-nitrophenyl azide with borontrichloride mainly affords chlorinated nitroanilines, whereas with borontrifluoride it gives N-o-nitrophenylaniline. In aromatic solvents at 60 °C in the presence of boron trifluoride–diethyl
TRANSITION METAL CATALYTIC SYSTEMS AND METHODS FOR PREPARING ETHYLENE HOMOPOLYMERS OR COPOLYMERS OF ETHYLENE AND OLEFINS USING THE SAME
申请人:Ok Myung Ahn
公开号:US20100048840A1
公开(公告)日:2010-02-25
Disclosed herein is a group IV transition metal catalyst for producing an ethylene homopolymer or an ethylene-olefin copolymers, having high catalytic activity, which includes a cyclopentadiene derivative and one or more anionic ligands having an aryl group substituted with an aryl derivative at an ortho-position thereof around a transition metal, the ligands not being crosslinked to each other, a catalyst system including the group IV transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst, and a method of producing ethylene homopolymers or ethylene-olefin copolymers using the catalyst system.
Transition metal catalytic systems and methods for preparing ethylene homopolymers or copolymers of ethylene and olefins using the same
申请人:Ok Myung Ahn
公开号:US08742043B2
公开(公告)日:2014-06-03
Disclosed herein is a group IV transition metal catalyst for producing an ethylene homopolymer or an ethylene-olefin copolymers, having high catalytic activity, which includes a cyclopentadiene derivative and one or more anionic ligands having an aryl group substituted with an aryl derivative at an ortho-position thereof around a transition metal, the ligands not being crosslinked to each other, a catalyst system including the group IV transition metal catalyst and an aluminoxane cocatalyst or a boron compound cocatalyst, and a method of producing ethylene homopolymers or ethylene-olefin copolymers using the catalyst system.
A Fully Integrated High-Throughput Screening Methodology for the Discovery of New Polyolefin Catalysts: Discovery of a New Class of High Temperature Single-Site Group (IV) Copolymerization Catalysts
作者:Thomas R. Boussie、Gary M. Diamond、Christopher Goh、Keith A. Hall、Anne M. LaPointe、Margarete Leclerc、Cheryl Lund、Vince Murphy、James A. W. Shoemaker、Ursula Tracht、Howard Turner、Jessica Zhang、Tetsuo Uno、Robert K. Rosen、James C. Stevens
DOI:10.1021/ja020868k
日期:2003.4.1
For the first time, new catalysts for olefin polymerization have been discovered through the application of fully integrated high-throughput primary and secondary screening techniques supported by rapid polymer characterization methods. Microscale 1-octene primary screening polymerization experiments combining arrays of ligands with reactive metal complexes M(CH2Ph)(4) (M = Zr, Hf) and multiple activation conditions represent a new high-throughput technique for discovering novel group (IV) polymerization catalysts. The primary screening methods described here have been validated using a commercially relevant polyolefin catalyst, and implemented rapidly to discover the new amide-ether based hafnium catalyst [eta(2)-(N,O)-(2-MeO-C6H4)(2,4,6-Me3C6H2)N]Hf(CH2Ph)(3) (1), which is capable of polymerizing 1-octene to high conversion. The molecular structure of I has been determined by X-ray diffraction. Larger scale secondary screening experiments performed on a focused 96-member amine-ether library demonstrated the versatile high temperature ethylene-1-octene copolymerization capabilities of this catalyst class, and led to significant performance improvements over the initial primary screening discovery. Conventional one gallon batch reactor copolymerizations performed using selected amide-ether hafnium compounds confirmed the performance features of this new catalyst class, serving to fully validate the experimental results from the high-throughput approaches described herein.
SPAGNOLO, PIERO;ZANIRATO, PAOLO, J. CHEM. SOC. PERKIN TRANS. PT I,(1988) N 9, C. 2615-2620