Sreedharan Prathapan

A New Method For The Generation of Nitriles From Aldoximes

Abstract A mild and efficient method for the stereoselective dehydration of α-aldoximes to the corresponding nitriles is described which utilises methyl (carboxysulfamoyl)triethylammonium hydroxide inner salt (Burgess reagent) as the dehydrating agent.

Preliminary investigations on the synthesis and antitumor activity of 3(2H)-furanones

Two triaryl-3(2H)-furanones were synthesized and their antitumor activity was evaluated. These compounds inhibited the proliferation of DLA cell line in vitro. In vivo studies also showed that these compounds were active against tumor cell proliferation.

OXIDATION OF BENZOIN TO BENZIL USING BURGESS REAGENT

ABSTRACT Synthetic utility of Burgess Reagent for the mild and efficient oxidation of benzoins to benzils is discussed.

Simple, Efficient, and Stereoselective Oxidation of Triphenylfurans to cis‐But‐2‐ene‐1,4‐diones

Abstract Triphenylfurans are stereoselctively oxidized to cis‐but‐2‐ene‐1,4‐diones, suitable precursors of 3(2H)‐furanones, in very good yields using ammonium nitrate or potassium nitrate in 80% aqueous acetic acid.

Simple and Efficient One-Pot Synthesis of Nitriles from Amides and Oximes Using in Situ–Generated Burgess-Type Reagent

Abstract The dehydration of aldoximes and amides, and oxidation of benzoin are accomplished in one-pot using in situ–generated Burgess-type reagent.

A novel solvent-assisted domino Michael-aldol reaction of acenaphthenequinone with acetophenonesElectronic supplementary information (ESI) available: 1H and 13C NMR spectra for 6a–c. See http://www.rsc.org/suppdata/nj/b2/b202454c/

Reaction of acenaphthenequinone with acetophenone in methanol in the presence of KOH provides a highly substituted dispiro compound in good yields arising through a novel three-component Michael-aldol domino reaction.

Diverse reactivity of nitrones towards electron deficient acetylenes

Depending on the nature of N- and C-substituents, nitrones exhibit diverse reactivity towards electron deficient acetylenes. Observed reactions include formal 1,3-dipolar cycloaddition and nucleophilic addition reactions. Possible involvement of zwitterionic intermediates and an unusual 1-aza-Cope rearrangement account for the generation of unexpected 1 : 1 adducts in the reaction of N-arylnitrones.

Novel Burgess reagent mediated C-to-N aryl migration reaction in nitrones

Nitrones undergo useful transformations with Burgess reagent. The reaction ostensibly involves a [3 + 2] annulation across a σ-bond followed by rearrangement involving C-to-N aryl migration. On the basis of available experimental evidence, plausible mechanisms for the rearrangement and the overall conversion have been proposed.

Effect of a Strategically Positioned Methoxy Substituent on the Photochemistry of 3-Aryl-3H-1-Oxacyclopenta[l]Phenanthren-2-Ones

Irradiation of 3-methoxy-3-aryl-3H-1-oxacyclopenta[l]phenanthren-2-one derivatives 5a–d resulted in singlet-mediated decarbonylation reaction leading to the formation of phenanthrene derivatives 9a–d. The structure of the photoproduct was unequivocally established on the basis of X-ray crystallographic analysis.

Efficient one-pot synthesis of (anthracen-9-yl)methyl sulfane derivatives

Abstract A series of unsymmetrical (anthracen-9-yl)methyl sulfanes have been synthesized using a one-pot reaction from (anthracen-9-yl)methyl alcohol, thiourea, and the corresponding alkyl halide and also by a base-promoted one-pot reductive coupling of tosylhydrazones with thiols.