83693-17-8Relevant academic research and scientific papers
CHEMICAL AND PHYSICAL PROPERTIES OF FLUORENYLIDENE: EQUILIBRATION OF THE SINGLET AND TRIPLET CARBENES.
Grasse,Brauer,Zupancic,Kaufmann,Schuster
, p. 6833 - 6845 (1983)
Irradiation of 9-diazofluorene, with a pulsed laser on a picosecond or nanosecond time scale at room temperature, or at 10 K in a glassy matrix, gives detectable fluorenylidene. This species is shown to exist, under most experimental conditions, as a rapi
The reaction of cyclopentadienylidine, fluorenylidene and tetrachlorocyclopentadienylidene with alcohols. A laser flash photolysis study
Olson, David R.,Platz, Matthew S.
, p. 759 - 769 (2007/10/03)
Rate constants of reaction of cyclopentadienylidene, fluorenylidene and tetrachlorocyclopentadienylidene with alcohols and other quenchers were determined by laser flash photolysis methods. The rate constants of reaction of cyclopentadienylidene and fluorenylidene with various alcohols were determined and found to increase with increasing alcohol acidity. Alcohols as a group reacted faster with cyclopentadienylidene and fluorenylidene than likely ylide formers such as pyridine, ethyl acetate and tetrahydrofuran. Bronsted plots of the reaction of cyclopentadienylidene and fluorenylidene with alcohols are linear with slopes of 0·061 and 0·082, respectively. In the case of tetrachlorocyclopentadienylidene, an ylide type of reaction mechanism with alcohols is indicated. Tetrachlorocyclopentadienylidene reacts most rapidly with the least acidic alcohol studied and this carbene reacts more rapidly with tetramethylurea, pyridine and tetrahydrofuran than with methanol.
THE REACTIONS OF FLUORENYLIDENE WITH HETEROATOMIC NUCLEOPHILES
Zupancic, Joseph J.,Grasse, Peter B.,Lapin, Stephen C.,Schuster, Gary B.
, p. 1471 - 1478 (2007/10/02)
The reaction of fluorenylidene with heteroatomic nucleophiles gives good yields of addition products.The rates of these reactions were determined using laser spectrophotometric techniques.Kinetic and product isotope effects were measured.The results of this investigation show that the reaction of the carbene with the nucleophile is not a one-step process.The implication of these conclusions to the spin selective reactions of carbenes and their utility as photoaffinity labels is discussed.
A Kinetic Study of the Reactions of Carbonyl Ylides Formed by the Addition of Fluorenylidene to Ketones
Wong, P. C.,Griller, D.,Scaiano, J. C.
, p. 6631 - 6635 (2007/10/02)
Fluorenylidene addds to aliphatic ketones to give carbonyl ylide intermediates.With acetone, for example, laser flash photolysis experiments showed that the rate constant for this reaction was 1 x 107 M-1 s-1 in acetonitrile solvent.The resulting carbonyl ylide had an absorption spectrum with λmax = 640 nm in the absence of quenchers underwent ring closure to the corresponding oxirane.The lifetimes, τy, for the ring closure reaction are described by the equation -log(τy/s) = (13.26 +/- 0.11) - (10.96 +/- 0.12) / θ where θ = 2.3RT kcal mol-1.The spectra of the carbonyl ylides could be quenched with rate constants of circa 107 M-1 s-1 by electron-deficient olefins or oxygen.
