Joseph C. Sloop

Synthesis of fluorinated heterocycles

Selected 1,3-diketones having a trifluoromethyl group and/or a fluorine in the 2-position were condensed with aromatic hydrazines, hydroxylamine, urea, thiourea, guanidine, and substituted anilines producing pyrazoles, isoxazoles, pyrimidines, and quinolines, respectively, in yields ranging from 27 to 87%.

Ring-fluorinated pyrazoles

Abstract 2-Fluoro-1,3-diketones react with phenylhydrazine to yield ring-fluorinated pyrazoles in high yield. An isoxazole is produced when 2-fluoro-1,3-diphenyl- 1,3-propandione is treated with hydroxylamine hydrochloride.

19-Fluorine nuclear magnetic resonance chemical shift variability in trifluoroacetyl species

This review examines the variability of chemical shifts observed in 19-fluorine ( 19 F) nuclear magnetic resonance spectra for the trifluoroacetyl (TFA) functional group. The range of 19 F chemical shifts reported spectra for the TFA group varies generally from −85 to −67 ppm relative to CFCl 3 . The literature revealed several factors that impact chemical shifts of the TFA moiety − substrate topology, electronic environment, solvent polarity, and concentration effects. Often these effects conspire to cause deshielding of the TFA group by up to 15 ppm. These factors will be examined for a series of TFA-functionalized acyclic, cyclic, aromatic, and heterocyclic molecules. 19 F NMR, chemical shift, shielding, trifluoroacetyl group, fluorinated diketones, triketones

New Diethyl Ammonium Salt of Thiobarbituric Acid Derivative: Synthesis, Molecular Structure Investigations and Docking Studies

The synthesis of the new diethyl ammonium salt of diethylammonium(E)-5-(1,5-bis(4-fluorophenyl)-3-oxopent-4-en-1-yl)-1,3-diethyl-4,6-dioxo-2-thioxohexaydropyrimidin-5-ide 3 via a regioselective Michael addition of N,N-diethylthiobarbituric acid 1 to dienone 2 is described. In 3, the carboanion of the thiobarbituric moiety is stabilized by the strong intramolecular electron delocalization with the adjacent carbonyl groups and so the reaction proceeds without any cyclization. The molecular structure investigations of 3 were determined by single-crystal X-ray diffraction as well as DFT computations. The theoretically calculated (DFT/B3LYP) geometry agrees well with the crystallographic data. The effect of fluorine replacement by chlorine atoms on the molecular structure aspects were investigated using DFT methods. Calculated electronic spectra showed a bathochromic shift of the π-π* transition when fluorine is replaced by chlorine. Charge decomposition analyses were performed to study possible interaction between the different fragments in the studied systems. Molecular docking simulations examining the inhibitory nature of the compound show an anti-diabetic activity with Pa (probability of activity) value of 0.229.

Advances in the Preparation of Fluorinated Isoquinolines: A Decade of Progress

Heterocyclic molecules incorporating fluorinated isoquinoline components are found in many medicinally and agriculturally important bioactive products as well as industrially impactful materials. Within the past decade, a variety of isoquinolinic ring assembly techniques has enabled the introduction of diverse fluorine-containing functionalities which can enhance potential bioactivity and industrial utility. This review examines recent noncatalyzed and transition metal catalyzed synthetic approaches to the assembly of isoquinoline derivatives that are ring-fluorinated and/or result in the incorporation of fluorine-containing functional groups. Specifically, efficient synthetic methods and regioselectivity in the incorporation of functional groups into isoquinoline ring systems are examined.