TY - JOUR
T1 - Iron-catalyzed olefin cis-dihydroxylation by H2O2
T2 - Electrophilic versus nucleophilic mechanisms
AU - Fujita, Megumi
AU - Costas, Miquel
AU - Que, Lawrence
PY - 2003/8/20
Y1 - 2003/8/20
N2 - Previous studies have classified a series of nonheme iron catalysts for olefin cis-dihydroxylation by H2O2 into two groups. Complex 1, [(TPA)Fe(OTf)2], representative of Class A catalysts, forms a low-spin FeIII-OOH intermediate that gives rise to a high-valent FeV(=O)OH oxidant. The preference of this catalyst for electron-rich olefins demonstrates its electrophilic character. On the other hand, complex 2, [(6-Me3-TPA)Fe(OTf)2], representative of Class B catalysts, prefers instead to oxidize electron-deficient olefins, suggesting an oxidant with nucleophilic character. It is suggested that such a nucleophilic oxidant may be the high-spin FeIII-OOH intermediate derived from 2 or the FeIV(=O)(•OH) species derived therefrom.
AB - Previous studies have classified a series of nonheme iron catalysts for olefin cis-dihydroxylation by H2O2 into two groups. Complex 1, [(TPA)Fe(OTf)2], representative of Class A catalysts, forms a low-spin FeIII-OOH intermediate that gives rise to a high-valent FeV(=O)OH oxidant. The preference of this catalyst for electron-rich olefins demonstrates its electrophilic character. On the other hand, complex 2, [(6-Me3-TPA)Fe(OTf)2], representative of Class B catalysts, prefers instead to oxidize electron-deficient olefins, suggesting an oxidant with nucleophilic character. It is suggested that such a nucleophilic oxidant may be the high-spin FeIII-OOH intermediate derived from 2 or the FeIV(=O)(•OH) species derived therefrom.
UR - http://www.scopus.com/inward/record.url?scp=0042021461&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0042021461&partnerID=8YFLogxK
U2 - 10.1021/ja029863d
DO - 10.1021/ja029863d
M3 - Article
C2 - 12914440
AN - SCOPUS:0042021461
SN - 0002-7863
VL - 125
SP - 9912
EP - 9913
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 33
ER -