6538-19-8Relevant articles and documents
THE SELECTIVE FUNCTIONALIZATION OF SATURATED HYDROCARBONS. PART 28. THE ACTIVATION OF BENZYLIC METHYLENE GROUPS UNDER GOAGGIV AND GOAGGV CONDITIONS
Barton, Derek H. R.,Wang, Tie-Lin
, p. 1011 - 1032 (2007/10/02)
Under GoAggIV and GoAggV conditions, cyclohexadienes were oxidized to give aromatic products instead of ketones and alcohols.At the same time, anthracene was oxidized to give anthraquinone.Under GoAggIV and GoAggV conditions, xanthene, fluorene and diphenylmethane were oxidized to give the corresponding xanthone, fluorenone and benzophenone following two possible pathways: a) alkane to alkyl t-butylperoxide to ketone, and b) alkane to ketone, in which alkyl hydroperoxide, derived from oxygen, may be the reaction intermediate.Xanthyl azide was formed when sodium azide was added to the reaction mixture of xanthene under GoAggIV and GoAggV conditions.The reaction of triphenylmethane under GoAggV conditions gave triphenylmethyl t-butyl peroxide as the major product and hydroperoxide as the minor product.When TEMPO was added, triphenylmethyl hydroperoxide was the only product.
Chemical and Physical Properties of 9-Xanthylidene: A Ground-State Singlet Aromatic Carbene
Lapin, Stephen C.,Schuster, Gary B.
, p. 4243 - 4248 (2007/10/02)
Irradiation of 9-diazoxanthene (DAX) leads to loss of N2 and formation of 9-xanthylidene (XA).This carbene was detected at low temperature in a frozen glass and by laser transient absorption spectroscopy.It reacts rapidly with alcohols to form ethers and with styrenes to give cyclopropanes stereospecifically.At room temperature, XA does not react significantly with hydrocarbons, but at elevated temperature, an insertion reaction characteristic of a singlet carbene is observed.Rate constants for these and other reactions are reperted.The data show that XA is a ground-state singlet carbene with a triplet state at least 4 kcal/mol above the singlet.This finding is incorporated into a general explanation of aromatic carbene reactivity.
