Phototautomerism of Warfarin Cation in Lowest Excited Singlet State via an Intramolecular Hydrogen Bridge

Yakatan, Gerald J.; Juneau, Richard

doi:10.1002/jps.2600610516

Cited by 15 publications

(1 citation statement)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the spectrum of the methoxylated compound is independent of solvent matrix, protonation is most probably at the hydroxyl oxygen. Literature data exists on the presence of three species in S 0 and S 1 [21,22]. However, the assignment of the emitting species is questionable, since it is suggested that at pH 2.4 a neutral excited species exists, while the cationic species is only reported for very strong acidic media [21].…”

Section: Absorbing and Emitting Tautomers 451 4hc And 4etcmentioning

confidence: 99%

Spectroscopy and photophysics of 4- and 7-hydroxycoumarins and their thione analogs

Melo

Fernandes

2001

Journal of Molecular Structure

149

127

View full text Add to dashboard Cite

Acid-base equilibria were studied for 4-hydroxycoumarin, 7-hydroxy-4-methylcoumarin and their thione derivatives in different media for their ground and lowest energy singlet and triplet excited states. The ethoxylated and/or methoxylated derivatives were also investigated. Characterization involves¯uorescence spectra, quantum yields, lifetimes, phosphorescence spectra, lifetimes, and triplet±triplet absorption spectra. From their pK a values it was found that 4 and 7-hydroxycoumarins are more acidic in their lowest excited singlet states than in S 0. The origin and character of the lowest singlet and triplet excited states is discussed.

show abstract

Section: Absorbing and Emitting Tautomers 451 4hc And 4etcmentioning

confidence: 99%

Spectroscopy and photophysics of 4- and 7-hydroxycoumarins and their thione analogs

Melo

Fernandes

2001

Journal of Molecular Structure

149

127

View full text Add to dashboard Cite

show abstract

ChemInform Abstract: DIE PHOTOTAUTOMERIE DES WARFARINKATIONS IM NIEDRIGST ANGEREGTEN SINGULETTZUSTAND UEBER EINE INTRAMOLEKULARE WASSERSTOFFBRUECKE

Yakatan¹,

Juneau²

1972

Chemischer Informationsdienst

View full text Add to dashboard Cite

show abstract

The chemistry of coumarin derivatives, part 2. Reaction of 4‐hydroxycoumarin with α,β‐unsaturated aldehydes

Appendino

Cravotto

Tagliapietra

et al. 1990

Helvetica Chimica Acta

View full text Add to dashboard Cite

4-Hydroxycoumarin ( = 4-hydroxy-2H-l-benzopyran-2-one) reacts with enals to give 1,2-or 1 ,Caddition products, depending on the nature and relative location of the substituents on the olefinic double bond (Scheme 2). The resulting adducts further react intra-or intermolecularly, affording dimeric coumarins or pyranocoumarins in the case of 1,2-addition and acetalic pyranocoumarins in the case of 1,Caddition. With enals bearing alkyl groups at CV), 2H-pyrano[3,2-c]coumarins are the only products formed, and the reaction represents an easy and straightforward entry into this class of recently described biologically active natural products.

show abstract

Phototautomerism of Warfarin Cation in Lowest Excited Singlet State via an Intramolecular Hydrogen Bridge

Cited by 15 publications

References 8 publications

Spectroscopy and photophysics of 4- and 7-hydroxycoumarins and their thione analogs

Spectroscopy and photophysics of 4- and 7-hydroxycoumarins and their thione analogs

ChemInform Abstract: DIE PHOTOTAUTOMERIE DES WARFARINKATIONS IM NIEDRIGST ANGEREGTEN SINGULETTZUSTAND UEBER EINE INTRAMOLEKULARE WASSERSTOFFBRUECKE

The chemistry of coumarin derivatives, part 2. Reaction of 4‐hydroxycoumarin with α,β‐unsaturated aldehydes

Contact Info

Product

Resources

About