Synthesis and thermal decomposition of hydrotrioxide obtained by ozonization of exo-bicyclo[2.2.1]heptan-2-ol

Abstract

Low temperature (-70 °С) ozonization of exo bicyclo[2.2.1]heptan 2 ol in CCl 3 F led to a hydrotrioxide, which was identified by 1 H NMR spectroscopy. Kinetics of decomposition of given hydrotrioxide was studied by analysis of the chemiluminescence fading in the IR range of the spectrum and the activation parameters of the process were calculated. Singlet oxygen ( 1 ∆ g ) served as an emitter of eradiation. Yields of 1 O 2 in a range of temperature from -31.0 to +12.5 °C were determined (at -31 °C the yield was 37.6%). Bicyclo[2.2.1]heptan 2 one was found to be the main product of decomposition of the hydrotrioxide (the yield was 98%).

Generation of Singlet Oxygen from Fragmentation of Monoactivated 1,1-Dihydroperoxides

“…6 Following the discovery of the chemical generation of 1 O 2 from the reaction of hydrogen peroxide and bleach, 7 a number of methods for “dark oxygenation” have been reported based upon decomposition of ozone, 8 hydrogen peroxide, 1a, 9,10,11,12,13 hydrotrioxides, 14,15 and several inorganic peroxides. 16,17 The majority of these methods require the use of water-enriched media, conditions associated with a very short 1 O 2 lifetime.…”

“…19 Generation of 1 O 2 in organic solvents has been achieved through thermal decomposition of calcium peroxide (suspension), 16 arene endoperoxides, 20 phosphite ozonides, 21 silyl hydrotrioxides, 14 and alkyl hydrotrioxides. 15 However, the latter class of reagents are often thermally unstable and must be prepared immediately prior to reaction. Major classes of reagents for chemical generation of 1 O 2 are overviewed below.…”

“…1 O 2 is most commonly generated through dye-sensitized excitation of ground-state dioxygen ( 3 O 2 ). , However, preparative application can be limited by the need for high-volume photoreactors, as well as by safety issues associated with reactions under oxygen . Following the discovery of the chemical generation of 1 O 2 from the reaction of hydrogen peroxide and bleach, a number of methods for “dark oxygenation” have been reported based upon decomposition of ozone, hydrogen peroxide, ,− hydrotrioxides, , and several inorganic peroxides. , The majority of these methods require the use of water-enriched media, conditions associated with a very short 1 O 2 lifetime . However, preparative oxidations have been achieved for relatively reactive substrates using biphasic or emulsion conditions .…”

“…However, preparative oxidations have been achieved for relatively reactive substrates using biphasic or emulsion conditions . Generation of 1 O 2 in organic solvents has been achieved through thermal decomposition of calcium peroxide (suspension), arene endoperoxides, phosphite ozonides, silyl hydrotrioxides, and alkyl hydrotrioxides . However, the latter class of reagents are often thermally unstable and must be prepared immediately prior to reaction.…”