13177-56-5Relevant academic research and scientific papers
Contrasting Photosolvolytic Reactivities of 9-Fluorenol vs 5-Suberenol Derivatives. Enhanced Rate of Formation of Cyclically Conjugated Four ? Carbocations in the Excited State
Wan, Peter,Krogh, Erik
, p. 4887 - 4895 (1989)
The photosolvolysis of 9-fluorenol (1) and several of its derivatives, as well as related systems, has been studied in aqueous methanol and acetonitrile solutions.The primary aim of this study was to examine the effect of the internal cyclic array (ICA) of these compounds in promoting photosolvolysis with respect to the number of ? electrons available in the ICA.It was observed that 9-fluorenol derivatives photosolvolyze much more efficiently than any of the related systems studied in this work.In contrast, ground-state 9-fluorenol derivatives are the least reactive systems with respect to solvolysis.Quantum yields for methyl ether formation for photosolvolysis in 50percent MeOH-H2O are reported for 1-3.Rate constants for solvent-assisted photodehydroxylation (ks) are calculated on the basis of the proposed mechanism of heterolytic C-OH bond rupture in the primary photochemical step and are in the range (1.3-1.6)x1E10 s-1 for 1-3.
Kinetic Isotope Effects for Proton Abstraction from Methanol by Polyhalogenomethyl Carbanions. Cleavage of Me3SiCHX2 and Me3SiCX3 by Base in Methanol.
Eaborn, Colin,Stanczyk, Wlodzimierz A.
, p. 471 - 473 (2007/10/02)
The carbanions XxH(3-x)C- (X=Cl or Br; x=2 or 3) generated by base cleavage of Me3SiCH(3-x)Xx (or some related compounds) in MeOH, show a kinetic isotope kH/kD of ca. 1.1 in proton abstraction from methanol, as given by the product ratio XxH(3-x)CH/XxH(3-x)CD observed for reaction in MeOH-MeOD (1:1) at ca. 21 deg C.The low value of the isotope effect is attributed to the fact that the free electron pair in the carbanion is localized on the carbon centre; carbanions derived from acids of acidities comparable with those of X3CH and X2CH2 but in which the electron pair is conjugatively delocalized, show much larger isotope effects.
