R. Kumareswaran

Chlorotrimethylsilane catalysed acylation of alcohols

A variety of alcohols are converted into the corresponding acetates upon treatment with acetic anhydride and catalytic amount of chlorotrimethylsilane in acetonitrile (or dichloromethane).

Studies in Lewis acid and LiClO4 (or Nafion-H) catalysed ionic Diels-Alder reactions of chiral and achiral olefinic acetals respectively☆☆☆

Abstract Chiral olefinic acetals derived from crotonaldehyde undergo ionic Diels-Alder reaction giving the corresponding cycloadducts in moderate to good diastereoselectivities. A variety of achiral olefinic acetals react with isoprene and cyclopentadiene to form the cycloadducts in good to excellent yields when catalysed by 4M LiClO4 in nitromethane or by Nafion-H in dichloromethane.

Indium trichloride: a useful catalyst for ionic Diels-Alder reactions

Abstract Indium trichloride (20 mol%) in nitromethane permits ionic Diels–Alder reaction of a variety of 2,3-olefinic acetals to form the corresponding cycloadducts in good yields with good endo selectivities.

A novel one pot synthesis of α-nitroketones from olefins using trimethylsilylnitrate-chromium trioxide reagent system

A variety of α-nitroketones have been obtained from the corresponding olefins in good yields upon reaction with trimethylsilylnitrate-chromium trioxide reagent system.

Nafion-H-catalyzed Mukaiyama aldol condensations and hetero Diels-Alder reactions using aldehydes and imines. Part 15: General synthetic methods

Abstract Nafion-H catalyzes the Mukaiyama aldol condensation between aromatic aldehydes and the Danishefsky diene whereas the corresponding imines directly undergo hetero Diels–Alder cyclization to form 2,3-dihydro-γ-pyridones. Some chiral acetal derived aldehydes were found to undergo Mukaiyama aldol condensation in the presence of Lewis acids but not with Nafion-H.

A one step conversion of olefins into α-Azidoketones using azidotrimethylsilane-chromium trioxide reagent system

Abstract α-Azidoketones are conveniently obtained in good yields from the corresponding olefins upon reaction with azidotrimethylsilane-chromium trioxide reagent system.

Palladium catalysed allylic substitution via in situ activation of allylic alcohols

In-situ activation of a variety of allylic alcohols by hexachlorophosphazene (or oxalyl chloride) followed by Pd(0) catalysed reactions with lithio dimethyl malonate leads to the regio and stereoselective alkylations in god yields.