70782-57-9Relevant academic research and scientific papers
The role of organic fluorine in directing alkylation reactions via lithium chelation
Tenza, Kenny,Northen, Julian S.,O'Hagan, David,Slawin, Alexandra M.Z.
, p. 1779 - 1790 (2007/10/03)
The fluorine of a fluoromethyl group displays a measurable chelation effect to lithium during α-methylation of an ester with lithium diisopropylamide (LDA) and methyl iodide. A series of esters is compared with F, H and O, and the resultant diastereoselectivity is consistent with the intermediate capacity of F to chelate lithium relative to H and O. In a second system which involved comparing a tertiary organic fluorine with hydrogen, no such effect is apparent, most probably due to adverse steric effects. The absolute and relative stereochemistry of the predominant diastereoisomers are confirmed by X-ray crystallography of suitable crystalline derivatives in each case. It is concluded that there is a potential role for organic-bound fluorine to become involved in lithium chelation in well-designed enolate alkylation systems. The diastereoselectivity of alkylation is explored comparing the coordination ability of H, F and OR substituents in the above model.
Derivatives of arylalkanoic acids, compositions and use
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, (2008/06/13)
There are now described some novel alpha-[1-aryl-2,2,2-trifluoroethoxy (or-ethylthio)]alkanoic acids that are useful for reducing triglycerides and cholesterol levels in the blood of animals. The percentage reduction in test rats has been observed to be from 20 to 65 for triglycerides and from 15 to 50 for cholesterol. A representative compound of the invention is alpha-(2,2,2-trifluoro-1-phenyl-1-ethoxy)butyric acid. Most of the compounds have an LD50 greater than 800 mg/kg, intraperitoneally, in male mice. A method of use, compositions, and a process for synthesis are also described.
