Abstract
A clean, mild, and efficient catalytic deoximation procedure compatible with several common functional groups has been developed using 30% hydrogen peroxide activated by iodine catalyst in aqueous acetonitrile under essentially neutral conditions. The mechanistic features of an iodonium ion–driven nucleophilic cleavage of oximic C[dbnd]N have been revealed.
ACKNOWLEDGMENTS
S. K. B. thanks the University of Kalyani for financial assistance by way of a research fellowship. Facilities provided by the Department of Science and Technology–Funding for Infrastructure in Science and Technology and the University Grants Commission, Government of India, are also acknowledged.
Notes
a Reaction conditions: 30% H2O2 (0.22 mL) and I2 (10 mol%) per mmol of substrate in acetonitrile–water (9:1), rt.
b Isolated yield upon column chromatography; the carbonyl compounds were characterized by their spectral data (FTIR, 1H NMR), mp, and comparison with authentic sample.[ Citation 12 ]
c Reaction conditions: 30% H2O2 (0.22 ml) and I2 (10 mol%) per mmol of substrate, MeOH, rt.
d Reaction conditions: 30% H2O2 (0.22 mL) and I2 (50 mol%), and MeOH (2 mL) per mmol of substrate; 4-hydroxy-3,5-diiodoacetophenone oxime (8a) was formed in a yield of 10%.
e The low yield of acetophenone is due to concomitant formation of 4-amino-3-iodoacetophenone oxime (9a) in 8% yield.
f Acetic acid was used as the solvent because of the low solubility of the substrate in aqueous acetonitrile.
g NR indicates no reaction.