Rajesh K.,Synthetic Organic Chemistry Research Laboratory |
Reddy B.P.,Synthetic Organic Chemistry Research Laboratory |
Balaji G.L.,Synthetic Organic Chemistry Research Laboratory |
Sarveswari S.,Synthetic Organic Chemistry Research Laboratory |
Vijayakumar V.,Synthetic Organic Chemistry Research Laboratory
Research on Chemical Intermediates | Year: 2012
Tracing of ethyl 2-acetyl-3-(phenylamino)butanoate intermediates (β-amino ketones) was performed during the course of N-arylpiperidone synthesis by reaction of aromatic amines, acetaldehyde, and ethyl acetoacetate. The structural confinement and stereochemistry of these molecules were explained by use of 2D NMR spectroscopy and X-ray crystallography. © Springer Science+Business Media B.V. 2012.
PubMed | Synthetic Organic Chemistry Research Laboratory
Type: Journal Article | Journal: The Journal of organic chemistry | Year: 2014
Chemoselective behavior of iodine in different solvents in the electrophilic iodocyclization of o-alkynyl aldehydes is described. o-Alkynyl aldehydes 3a-t on reaction with I2 in CH2Cl2 with appropriate nucleophiles provides pyrano[4,3-b]quinolines 4a-f, via formation of cyclic iodonium intermediate Q; however, using alcohols as a solvent as well as nucleophile, o-alkynyl esters 5a-y were obtained selectively in good to excellent yields via formation of hypoiodide intermediate R. Subsequently, o-alkynyl esters were converted in to pyranoquinolinones 6a-i and isocoumarin 6j by electrophilic iodocyclization. This developed oxidative esterification provides a novel access for the chemoselective synthesis of esters 5q-u from aldehydes 3n-p without oxidizing primary alcohol present in the substrate.