703-55-9Relevant articles and documents
Enantioselective Construction of Tertiary Fluoride Stereocenters by Organocatalytic Fluorocyclization
Biosca, Maria,Eriksson, Lars,Hedberg, Martin,Himo, Fahmi,Lübcke, Marvin,Szabó, Kálmán J.,Wang, Qiang
supporting information, p. 20048 - 20057 (2020/11/27)
1,1-Disubstituted styrenes with internal oxygen and nitrogen nucleophiles undergo oxidative fluorocyclization reactions with in situ generated chiral iodine(III)-catalysts. The resulting fluorinated tetrahydrofurans and pyrrolidines contain a tertiary carbon-fluorine stereocenter. Application of a new 1-naphthyllactic acid-based iodine(III)-catalyst allows the control of tertiary carbon-fluorine stereocenters with up to 96% ee. Density functional theory calculations are performed to investigate the details of the mechanism and the factors governing the stereoselectivity of the reaction.
Bismuth-catalyzed synthesis of polycyclic aromatic hydrocarbons (PAHs) with a phenanthrene backbone via cyclization and aromatization of 2-(2-arylphenyl)vinyl ethers
Murai, Masahito,Hosokawa, Naoki,Roy, David,Takai, Kazuhiko
supporting information, p. 4134 - 4137 (2014/09/30)
The reaction of 2-(2-arylphenyl)vinyl ethers in the presence of a catalytic amount of bismuth(III) triflate gave substituted phenanthrenes in excellent yields under mild reaction conditions. The reaction was also applied to the construction of other polycyclic aromatic hydrocarbons (PAHs), such as chrysene, helicene, and pyrene having a phenanthrene backbone, via regioselective cyclization. This method has the advantages of easy availability of the cyclization precursors, operational simplicity, and high reaction efficiency.
Heteroatom bridged metallocene compounds for olefin polymerization
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, (2008/06/13)
This invention relates to a transition metal compound represented by the formula: wherein M is a group 3, 4, 5 or 6 transition metal atom, or a lanthanide metal atom, or actinide metal atom; E is: 1) a substituted or unsubstituted indenyl ligand that is bonded to Y through the four, five, six or seven position of the indenyl ring, or 2) a substituted or unsubstituted heteroindenyl ligand that is bonded to Y through the four, five or six position of the heteroindenyl ring, provided that the bonding position is not the same as the position of the ring heteroatom, or 3) a substituted or unsubstituted fluorenyl ligand that is bonded to Y through the one, two, three, four, five, six, seven or eight position of the fluorenyl ring, or 4) a substituted or unsubstituted heterofluorenyl ligand that is bonded to Y through the one, two, three, four, five or six position of the heteroindenyl ring, provided that the bonding position is not the same as the position of the ring heteroatom; A is a substituted or unsubstituted cyclopentadienyl ligand, a substituted or unsubstituted heterocyclopentadienyl ligand, a substituted or unsubstituted indenyl ligand, a substituted or unsubstituted heteroindenyl ligand, a substituted or unsubstituted fluorenyl ligand, a substituted or unsubstituted heterofluorenyl ligand, or other mono-anionic ligand; Y is a Group 15 or 16 bridging heteroatom substituent that is bonded via the heteroatom to E and A; and X are, independently, univalent anionic ligands, or both X are joined and bound to the metal atom to form a metallocycle ring, or both X join to form a chelating ligand, a diene ligand, or an alkylidene ligand. This invention further relates to catalyst systems comprising the above transiotioon metal compounds, activators and optional supports and their use to polymerize or oligomerize olefins.