TY - JOUR
T1 - Metal-free activation of H 2O 2 by synergic effect of ionic liquid and microwave
T2 - Chemoselective oxidation of benzylic alcohols to carbonyls and unexpected formation of anthraquinone in aqueous condition
AU - Kumar, Rakesh
AU - Sharma, Nandini
AU - Sharma, Naina
AU - Sharma, Abhishek
AU - Sinha, Arun K.
PY - 2011/8
Y1 - 2011/8
N2 - H 2O 2 mediated oxidation of alcohols in ionic liquid is revisited, wherein, ionic liquids under the influence of microwave irradiation have been found to facilitate activation of H 2O 2 without any metal catalyst in aqueous condition. The method utilizes a neutral ionic liquid [hmim]Br both as catalyst and solvent for efficient and chemoselective oxidation of benzyl alcohol derivatives on aromatic (β, γ) alcohols, cyclic and aliphatic analogues, which can be a useful synthetic approach in total synthesis of complex organic compounds/natural products. Moreover, an unexpected oxidation of 9-anthracenyl propanol, a polyaromatic benzyl alcohol, resulting in the formation of 9,10-anthraquinone by the loss of propyl side chain was observed. Plausible mechanism and further exploration of this method on various other related substrates are discussed in detail.
AB - H 2O 2 mediated oxidation of alcohols in ionic liquid is revisited, wherein, ionic liquids under the influence of microwave irradiation have been found to facilitate activation of H 2O 2 without any metal catalyst in aqueous condition. The method utilizes a neutral ionic liquid [hmim]Br both as catalyst and solvent for efficient and chemoselective oxidation of benzyl alcohol derivatives on aromatic (β, γ) alcohols, cyclic and aliphatic analogues, which can be a useful synthetic approach in total synthesis of complex organic compounds/natural products. Moreover, an unexpected oxidation of 9-anthracenyl propanol, a polyaromatic benzyl alcohol, resulting in the formation of 9,10-anthraquinone by the loss of propyl side chain was observed. Plausible mechanism and further exploration of this method on various other related substrates are discussed in detail.
KW - Hydrogen peroxide
KW - Ionic liquids
KW - Metal-free
KW - Microwave
KW - Oxidation
UR - http://www.scopus.com/inward/record.url?scp=80051578830&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80051578830&partnerID=8YFLogxK
U2 - 10.1007/s11030-010-9292-z
DO - 10.1007/s11030-010-9292-z
M3 - Article
C2 - 21113797
AN - SCOPUS:80051578830
SN - 1381-1991
VL - 15
SP - 687
EP - 695
JO - Molecular Diversity
JF - Molecular Diversity
IS - 3
ER -