A DABCO-copper(I) chloride complex (5 mol%) together with TEMPO (5 mol%) in nitromethane as solvent has been used as an efficient catalytic system for the selective oxidation of benzylic and allylic alcohols into the corresponding carbonyl compounds at room temperature where molecular oxygen acts as an ultimate, stoichiometric oxidant and water is the only by-product. The solidstate structure determination of the DABCOcopper complex shows that the copper is in the + II oxidation state with trigonal bipyramidal geometry and exists in a linear polymeric structure due to strong hydrogen bonding. © 2007 Wiley-VCH Verlag GmbH & Co. KGaA.

Govindasamy Sekar

Department Of Chemistry

Sreedevi Mannam

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Advanced Synthesis and Catalysis

A wide range of 2-aryl or 2-alkyl-substituted benzothiazoles are synthesized through intramolecular C(aryl)-S bond forming-cyclization using copper(II)-BINAM-catalyzed coupling of less reactive N-(2-chlorophenyl) benzo or alkylthioamide under mild reaction conditions (82 °C). © 2010 Elsevier Ltd. All rights reserved.

Tetrahedron Letters

An efficient copper(II)-catalyzed synthesis of benzothiazoles through intramolecular coupling-cyclization of N-(2-chlorophenyl)benzothioamides

A wide range of arylated alkynes are synthesized from the corresponding aryl halides and terminal alkynes through Sonogashira type cross-coupling reactions through C(aryl)-C bond formation in the presence of a catalytic amount of N,N′-dibenzyl BINAM-CuI complex under mild reaction conditions. © 2009 Elsevier Ltd. All rights reserved.

An efficient copper(I) complex catalyzed Sonogashira type cross-coupling of aryl halides with terminal alkynes

A wide range of N-arylated indoles are selectively synthesized through intermolecular C(aryl)-N bond formation from the corresponding aryl iodides and indoles through Ullmann-type coupling reactions in the presence of a catalytic amount of easily available N,N,N′,N′-tetramethyl-BINAM-CuI complex under very mild reaction conditions. © 2009 Elsevier Ltd. All rights reserved.

Tetrahedron

An efficient, mild, and selective Ullmann-type N-arylation of indoles catalyzed by copper(I) complex

A study was conducted to demonstrate chiral cobalt-catalyzed enantiomer-differentiating oxidation of racemic benzoins using molecular oxygen as stoichiometric oxidant. The cobalt-catalyzed asymmetric oxidation was performed with racemic benzoins due to their importance in pharmaceutical industry and difficulty in synthesizing them in enantiomerically pure form. The investigation was conducted with (±)-4-methoxy benzoin as model substrate for oxidative kinetic resolution. The oxidation took 7 d for 44% conversion and provided 41% of 4-methoxy benzil when (±)-4-methoxy benzoin was reacted with 5 mol% of TEMPO and 5 mol% of enantiopure (L)-proline-Co(OAc)2 complex in the presence of molecular oxygen at room temperature. It was observed that 52% of 4-methoxy benzoin was recovered with 4% enantiomeric excess and selectivity in the asymmetric oxidation reaction.

Chemistry - A European Journal

Chiral cobalt-catalyzed enantiomer-differentiating oxidation of racemic benzoins by using molecular oxygen as stoichiometric oxidant

An enantiopure galactose oxidase (GO) enzyme model has been synthesized from readily available (R)-BINAM and Cu(OTf)2, and the enantiopure GO model has been effectively used in situ as an efficient chiral catalyst for the synthesis of chiral amino alcohols through oxidative kinetic resolution (OKR), where molecular oxygen is used as the sole oxidant. Under the proposed catalytic conditions, both ortho- and para-substituted amino alcohols were resolved with good to excellent enantiomeric excesses through oxidative kinetic resolution. © 2009 Elsevier Ltd. All rights reserved.

Journal	Advanced Synthesis and Catalysis
ISSN	16154150
Open Access	No