Study of epoxidation of cis-cyclooctene with iodosylbenzene in presence of metal complex and light as catalysts

Samnani, Prakash B.; Bhattacharya, P. K.

doi:10.1016/s1381-1169(97)00088-5

Cited by 3 publications

(2 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nam and Valentine and Yang et al concluded that some metal-catalyzed iodosylbenzene reactions that had previously been assumed to proceed via high-valent metal oxo intermediates actually occur without the participation of redox active metals. More recently, it was found that, in the presence of light, epoxidation of cis -cyclooctene with PhIO occurs even in the absence of metals . Our spectroscopic study rules out the formation of a ferric hydroperoxo species from [Fe III PMA] 2+ with PhIO and supports the view that PhIO-mediated oxotransfer reactions may occur without the formation of a hypervalent metal intermediate.…”

Section: Discussionsupporting

confidence: 83%

“…More recently, it was found that, in the presence of light, epoxidation of cis-cyclooctene with PhIO occurs even in the absence of metals. 47 Our spectroscopic study rules out the formation of a ferric hydroperoxo species from [Fe III PMA] 2+ with PhIO and supports the view that PhIO-mediated oxotransfer reactions may occur without the formation of a hypervalent metal intermediate. Furthermore, an apparent discrepancy between the behavior of Fe III BLM and [Fe III PMA] 2+ with PhIO has been clarified.…”

Section: Discussionsupporting

confidence: 81%

See 1 more Smart Citation

EPR Spectroscopic Reinvestigation of the Activation of Iron Complexes of PMAH as a Bleomycin Model

1998

View full text Add to dashboard Cite

The structure and reactivity of iron complexes of PMAH, which contains ligands that mimic the metal binding domain of iron bleomycin (FeBLM), have been studied using EPR spectroscopy. It had been reported [Guajardo, R. J.; Hudson, S. E.; Brown, S. J.; Mascharak, P. K. J. Am. Chem. Soc. 1993, 115, 7971] that iron complexes of PMAH can be activated to a ferric hydroperoxide, a structural analog by activated BLM, by various routes, including reaction of [FeIIIPMA]2+ with iodosylbenzene (PhIO), methanol, and base. We show that with or without PhIO, the latter reaction produces the methoxide complex of FeIIIPMA, and not the hydroperoxide, contrary to the previous report. Thus, O−O bond formation through generation of a ferric hydroperoxide does not occur. The same methoxide complex (g = 2.28, 2.18, 1.93) is generated by the addition of organic base and CH3OH, or LiOCH3, to [FeIIIPMA]2+. The formation of this [CH3O−FeIIIPMA]+ complex is confirmed by EPR titration of [FeIIIPMA]2+ with -OCH3 and by electrospray mass spectrometry. In contrast, the hydroperoxy complex of FeIIIPMA (g = 2.22, 2.17, 1.94) can be generated by the reaction of [FeIIIPMA]2+ with hydrogen peroxide or during aerobic oxidation of [FeIIPMA]+. The present results illustrate that activation of iron complexes of PMAH occur under conditions that produce activated BLM and further demonstrate that reaction of [FeIIIPMA]2+ with PhIO and base does not provide a route to either a hypervalent iron species or a hydroperoxide intermediate. These results agree with the finding that PhIO cannot be used to generate activated bleomycin [Sam, J. W.; Tang, X.-J.; Magliozzo, R. S.; Peisach, J. J. Am. Chem. Soc. 1995, 117, 1012].

show abstract

Section: Discussionsupporting

confidence: 83%

Section: Discussionsupporting

confidence: 81%

EPR Spectroscopic Reinvestigation of the Activation of Iron Complexes of PMAH as a Bleomycin Model

1998

View full text Add to dashboard Cite

show abstract

Development of a General and Efficient Iron‐Catalyzed Epoxidation with Hydrogen Peroxide as Oxidant

Bitterlich

Anilkumar

Gelalcha

et al. 2007

Chemistry An Asian Journal

View full text Add to dashboard Cite

The development of inexpensive and practical iron catalysts for the environmentally benign epoxidation of olefins with hydrogen peroxide as terminal oxidant is described. By systematic variation of ligands, metal sources, and reaction conditions, it was discovered that FeCl3 x 6 H2O in combination with pyridine-2,6-dicarboxylic acid and different amines shows high reactivity and excellent selectivity towards the epoxidation of aromatic olefins and moderate reactivity towards that of aliphatic olefins.

show abstract

Study of olefin epoxidation using binuclear Mn(II) complexes as catalyst in presence and absence of UV light

Sureshan

Bhattacharya

1998

Journal of Molecular Catalysis A: Chemical

View full text Add to dashboard Cite

Study of epoxidation of cis-cyclooctene with iodosylbenzene in presence of metal complex and light as catalysts

Cited by 3 publications

References 8 publications

EPR Spectroscopic Reinvestigation of the Activation of Iron Complexes of PMAH as a Bleomycin Model

EPR Spectroscopic Reinvestigation of the Activation of Iron Complexes of PMAH as a Bleomycin Model

Development of a General and Efficient Iron‐Catalyzed Epoxidation with Hydrogen Peroxide as Oxidant

Study of olefin epoxidation using binuclear Mn(II) complexes as catalyst in presence and absence of UV light

Contact Info

Product

Resources

About