145983-08-0Relevant academic research and scientific papers
Halogen substituted metallocene compounds for olefin polymerization
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, (2008/06/13)
A metallocene compound is represented by the formula (1): wherein: M is a Group 3, 4, 5 or 6 transition metal atom, or a lanthanide metal atom, or actinide metal atom, preferably a Group 4 transition metal atom selected from titanium, zirconium or hafnium; E is a substituted or unsubstituted monocyclic or polycyclic arenyl ligand pi-bonded to M; A is a substituted or unsubstituted polycyclic arenyl ligand that is pi-bonded to M and has a different ring structure than the E ligand; at least one of the A and E ligands includes at least one halogen substituent directly bonded to an sp2 carbon at a bondable ring position; Y is a bridging group containing at least one Group 13, 14, 15, or 16 element and any single position of the ring structure of A and to any single position of the ring structure of E; and y is zero or 1, indicating the absence (y=0) or presence (y=1) of Y; and each X is a univalent anionic ligand, or two X are joined and bound to the metal atom to form a metallocycle ring, or two X are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand; provided that when E is an unsubstituted cyclopentadienyl ligand, either y is one or A is not 2-bromofluorenyl or 2,7-dibromofluorenyl.
Microbial asymmetric decarboxylation of fluorine-containing arylmalonic acid derivatives
Miyamoto, Kenji,Tsuchiya, Shigeo,Ohta, Hiromichi
, p. 225 - 232 (2007/10/02)
α-Methyl-α-(trifluoromethylphenyl)malonic acids have been incubated with Alcaligenes bronchisepticus to afford optically active α-arylpropionic acids.Generally, the chemical and optical yields of the reaction products were higher when the substituents on the aromatic ring were strongly electron-withdrawing.Decarboxylation of α-fluoro-α-phenylmalonic acid with the aid of the same bacterium afforded optically active α-fluoro-α-phenylacetic acid.
