148892-95-9Relevant academic research and scientific papers
Comparative Lewis acidity in fluoroarylboranes: B(o-HC6F 4)3, B(p-HC6F4)3, and B(C6F5)3
Morgan, Matthew M.,Marwitz, Adam J. V.,Piers, Warren E.,Parvez, Masood
, p. 317 - 322 (2013/02/25)
The Lewis acidic fluoroarylborane B(o-HC6F4) 3 (2) was prepared and its Lewis acid strength assessed in comparison to the known, related boranes B(C6F5)3 (1) and B(p-HC6F4/
Dihydrogen activation by B(p-C6F4H)3 and phosphines
Ullrich, Matthias,Lough, Alan J.,Stephan, Douglas W.
, p. 3647 - 3654 (2010/10/04)
The Grignard reagent (p-C6F4H)MgCl was used to prepare (Et2O)B(p-C6F4H)3 (2) and the free borane B(p-C6F4H)3 (1). On the basis of Lewis acidity tests, the borane 1 exhibits ca. 95% of the acidity of B(C 6F5)3. 1 forms classical adducts with ethers and phosphines of the general formula (L)B(p-C6F4H) 3 (L = Et2O (2), THF (3), Me3P (4), Et 3P (5), i-Pr2(H)P (6), Ph3P (7), (3,5-Me 2C6H3)3P (8), t-Bu2(H)P (9), and Cy3P (10)). Compounds 9 and 10 react with 4 atm of H 2 to give the salts [t-Bu2PH2][HB(p-C 6F4H)3] (11) and [Cy3PH][HB(p-C 6F4H)3] (12). The sterically demanding phosphines R3P (R = t-Bu, i-Pr, 2,4,6-Me3C 6H2, and 2-MeC6H4), R 2R′P (R,R′ = t-Bu, i-Pr and t-Bu, Cy), and (Ph 2CH)R2P (R = t-Bu (22), i-Pr (23), Cy (24), and C 5H9 (25)) show no evidence of adduct formation with 1, but react with H2 to give the corresponding salts [R3PH] [HB(p-C6F4H)3] (13-16), [R2R′ PH][HB(p-C6F4H)3] (17-20), and [(Ph 2CH)R2PH][HB(p-C6F4H)3] (26-29), respectively. The [t-Bu2PH2]+ species 11 is stable only under an H2 overpressure, while the [t-Bu 3PH]+ salt 13 cleanly extrudes isobutene and H2 at elevated temperatures to give 9. The [(2-MeC6H4) 3PH]+ derivative 16 readily liberates H2 under vacuum, thus providing a metal-free system capable of reversible H2 uptake and release. Crystallographic data for compounds 1, 5, 8, 9, 10, 13, and 26 are reported.
Catalyst system for the polymerization of olefins
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, (2008/06/13)
An organometallic compound obtainable by contacting a) a compound having the following formula (I): wherein Ra, Rb, Rcand Rdequal to or different from each other are hydrocarbon groups b) a Lewis acid of formula (II) MtR13??(II) wherein Mt is a metal belonging to Group 13 of the Periodic Table of the Elements (IUPAC); R1, equal to or different from each other, are selected from the group consisting of halogen, halogenated C6-C20aryl and halogenated C7-C20alkylaryl groups; two R1groups can also form with the metal Mt one condensed ring. These compounds are useful as cocatalysts for polymerizing olefins.
Transition metal compound, catalyst for addition polymerization, and process for producing addition polymer
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, (2008/06/13)
A transition metal compound (A) of the formula (1), a catalyst for addition polymerization obtained by bringing the transitionmetal compound to contact with (B) and/or (C) below, and a process for producing an addition polymer with the catalyst: wherein, M represents a titanium atom, zirconium atom or hafnium atom in the +3 formal oxide condition; A represents a multidentate mono-anionic ligand; R1 represents an alkyl group, aralkyl group, aryl group or substituted silyl group; E represents an oxygen atom or sulfur atom; each of two Xs independently represents a hydrogen atom, halogen atom, alkyl group, aralkyl group, aryl group, substituted silyl group, alkoxy group, aralkyloxy group, aryloxy group or di-substituted amino group, and two Xs may bond mutually to form a ring; D represents a neutral ligand coordinated on M; and n represents an integer of from 0 to 2.), (B)Organic aluminum compound and/or aluminoxane, (C)Specific boron compound.
