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Efficient Catalytic Activity of Transition Metal Ions in Vilsmeier–Haack Reactions with Acetophenones
Author(s) -
Aneesa F.,
Rajanna K. C.,
Venkateswarlu M.,
Reddy K. Rajendar,
Kumar Y. Arun
Publication year - 2013
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.20807
Subject(s) - chemistry , catalysis , reagent , acetonitrile , transition metal , kinetics , ternary operation , formylation , metal , inorganic chemistry , ion , metal ions in aqueous solution , medicinal chemistry , photochemistry , organic chemistry , physics , quantum mechanics , computer science , programming language
Vilsmeier–Haack (VH) formylation reactions with acetophenones are sluggish in acetonitrile medium even at elevated temperatures. However, millimolar concentrations of transition metal ions such as Cu(II), Ni(II), Co(II), and Cd(II) were found to exhibit efficient catalytic activity in Vilsmeier–Haack Reactions with acetophenones. Reactions are accelerated remarkably in the presence of transition metal ions. The VH reactions followed second order kinetics and afforded acetyl derivatives under kinetic conditions also irrespective of the nature of oxychloride (POCl 3 or SOCl 2 ) used for the preparation of VH reagent along with DMF. On the basis of UV–vis spectroscopic studies and kinetic observations, participation of a ternary precursor [M(II) S (VHR)] in the rate‐limiting step has been proposed to explain the mechanism of the metal ion–catalyzed VH reaction.