@article { ISI:000256178900015, title = {Selective cis-dihydroxylation of olefins using recyclable homogeneous molybdenum acetylide catalyst}, journal = {Journal of Molecular Catalysis A-Chemical}, volume = {285}, number = {1-2}, year = {2008}, month = {APR}, pages = {111-119}, publisher = {ELSEVIER SCIENCE BV}, address = {PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS}, abstract = {

Selective cis-dihydroxylation of various olefins has been carried out using molybdenum acetylide complex CpMO(CO)(3)(C CPh) (1) as catalyst and hydrogen peroxide as an efficient and environmentally benign oxidant. In case of cyclohexene, very high conversion (95\%) and selectivity (86\%) for cis-dihydroxylated product has been achieved using H2O2 as an oxidant and t-butanol as a solvent. cis-Dihydroxylation of other substrates like styrene, a-methyl styrene, limonene and cyclopentene has also been carried out with very high selectivity for diol. The catalyst and intermediate species have been characterized using FT-IR, UV-vis spectral analysis and XPS studies as well as cyclic voltametric studies. These studies suggest that molybdenum oxo-peroxo complex is the catalytically active species. The intermediate blue complex when characterized by ESI MS suggested the formation of dimeric molybdenum complex and XPS and cyclic voltametric studies confirm the presence of mixed valence Mo(V) and Mo(VI) in the reaction intermediate. Based on the characterization results possible mechanism for dihydroxylation is proposed. Interestingly, even though the catalyst is homogeneous; it could be recovered quantitatively by extraction in aqueous phase and recycled five times without any appreciable loss in cyclohexene conversion and selectivity for cis-1,2-cyclohexanediol. (c) 2008 Elsevier B.V. All rights reserved.

}, keywords = {acetylide complex, cis-dihydroxylation, Homogeneous catalysis, Hydrogen peroxide, recyclable}, issn = {1381-1169}, doi = {10.1016/j.molcata.2008.01.034}, author = {Biradar, Ankush V. and Sathe, Bhaskar R. and Shubhangi B. Umbarkar and Dongare, Mohan K.} } @article { ISI:000256043100018, title = {Selective N-oxidation of aromatic amines to nitroso derivatives using a molybdenum acetylide oxo-peroxo complex as catalyst}, journal = {Tetrahedron Letters}, volume = {49}, number = {22}, year = {2008}, month = {MAY}, pages = {3616-3619}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

The molybdenum acetylide oxo-peroxo complex obtained in situ by the treatment of the corresponding molybdenum acetylide carbonyl complex, CpMo(CO)(3)(C CPh); Cp = eta(5-)C(5)H(5) with H(2)O(2), has been used as an efficient catalyst for selective N-oxidation of primary amines to nitroso derivatives. Excellent amine conversion (up to 100\%) and very high selectivity for nitroso compounds (99\%) have been obtained using 30\% hydrogen peroxide as an oxidant. The oxo peroxo, Mo(VI) complex has also been found to be very active for the oxidation of various substituted primary aromatic amines with electron donating as well as electron withdrawing substituents on the aromatic ring. (C) 2008 Elsevier Ltd. All rights reserved.

}, keywords = {aromatic amine, Homogenous catalyst, Hydrogen peroxide, Molybdenum complex, nitroso, Oxidation, Oxo-peroxo}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2008.04.005}, author = {Biradar, Ankush V. and Kotbagi, Trupti V. and Dongare, Mohan K. and Shubhangi B. Umbarkar} } @article { ISI:000266188300010, title = {Selective oxidation of aromatic primary alcohols to aldehydes using molybdenum acetylide oxo-peroxo complex as catalyst}, journal = {Tetrahedron Letters}, volume = {50}, number = {24}, year = {2009}, month = {JUN}, pages = {2885-2888}, publisher = {PERGAMON-ELSEVIER SCIENCE LTD}, address = {THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND}, abstract = {

Selective oxidation of various aromatic alcohols to aldehydes has been carried out with very high conversion (90\%) and selectivity (90\%) for aldehydes using cyclopentadienyl molybdenum acetylide complex, CpMo(CO)(3)(C CPh) (1) as catalyst and hydrogen peroxide as environmentally benign oxidant, Water-soluble Mo acetylide oxo-peroxo species is formed in situ after reaction of I with aqueous hydrogen peroxide during the Course of reaction as catalytically active species. Interestingly even though the catalyst is homogeneous it Could be recycled very easily by separating the products in organic phase and catalyst in aqueous phase using separating funnel. Even after five recycles no appreciable loss in alcohol conversion and aldehyde selectivity was observed. (C) 2009 Elsevier Ltd. All rights reserved.

}, keywords = {Homogenous catalyst, Hydrogen peroxide, Molybdenum complex, Oxidation, Oxo-peroxo, Primary aromatic alcohol}, issn = {0040-4039}, doi = {10.1016/j.tetlet.2009.03.178}, author = {Biradar, Ankush V. and Dongare, Mohan K. and Shubhangi B. Umbarkar} }