K. Koteswara Rao

Layered double hydroxide fluoride: a novel solid base catalyst for C–C bond formation

LDH-F hydrotalcite catalysts are found to be an efficient, environmentally attractive and selective solid base catalysts for 1,4-Michael addition and also for simple synthesis of α,β-unsaturated esters and nitriles by Knoevenagel condensation. The catalyst displayed unprecedented catalytic activity both in Knoevenagel and Michael reactions under mild liquid phase conditions at a greater rate compared with known solid bases and fluoride catalysts. The present ecofriendly catalyst is a potential alternative to soluble bases.

Hydrogenation of acetylenics by Pd-exchanged mesoporous materials

Pd/Si-K10 and Pd/MCM-41 were prepared by exchange in organic media of mesoporous Si modified K10 clay and Na-Al-MCM-41 and the efficiency of these catalysts versus microporous Pd/Y-zeolite is reported in the hydrogenation in the liquid phase of olefins, acetylenes and semi-hydrogenation of acetylenes.

Aldol and Knoevenagel condensations catalysed by modified Mg–Al hydrotalcite: a solid base as catalyst useful in synthetic organic chemistry

Aldol and Knoevenagel condensations were performed with suitably activated Mg–Al hydrotalcite as catalyst in quantitative yields in the liquid phase under mild reaction conditions at a faster rate for the first time.

Henry reactions catalysed by modified Mg–Al hydrotalcite:. an efficient reusable solid base for selective synthesis of β-nitroalkanols†

Henry reactions have been performed for the first time with suitably activated Mg–Al hydrotalcite as catalyst in quantitative yields in the liquid phase under mild reaction conditions and with low reaction times. Exclusive synthesis of β-nitroalkanols (3) is realised by the compatible basic Bronsted hydroxy sites of the modified hydrotalcite. Reusability with consistent activity and selectivity for a number of cycles is established indicating that the hydrated hydrotalcite employed here is a potentially eco-friendly catalyst which can replace soluble bases in commercial synthesis.

A novel molecular recognition in montmorillonite in the arylation of acrylates

A novel sequential and preferential substrate selectivity in arylation of acrylates with iodobenzenes by interlamellar montmorilloniteethylsilyldiphenylphosphinepalladium(II) chloride catalyst is reported for the first time.

Selective nitration of aromatic compounds by solid acid catalysts

High activity and para-selectivity in the nitration of aromatic compounds is achieved by a high density of acidic sites and ready formation of the para-isomer in the pores of zeolite beta with low Si/Al ratio as revealed by molecular modeling studies.

Acylation of Amines with Carboxylic Acids: The Atom Economic Protocol Catalysed by Fe(III)-Montmorillonite

An efficient and selective acylation of amines employing carboxylic acid as acylating agent was realised for the first time through tuning up of acidic sites of montmorillonite K10 achieved by incorporation of the right choice of exchangeable cations.

Conversion of Primary Amines to N,N′-Disubstituted Ureas Using Montmorillonitebipyridinepalladium(II)-acetate and Di-Tert Butyl Peroxide

Abstract A simple and convenient methodology for the synthesis of N,N′-disubstituted ureas from primary amines by a heterogenized catalyst montmorillonitebipyridinepalladium (II)acetate for the first time at room temperature and atmospheric pressure is described.

An efficient heterogenised palladium catalytic system for the reductive carbonylation of nitrobenzene to methyl N-phenylcarbamate

A highly active and selective heterogenised homogeneous catalyst, montmorillonitebipyridinepalladium (II) acetate complex for the reductive carbonylation of nitrobenzene to methyl N-phenylcarbamate is reported. With the additional advantages such as ease of filterability and reusability for several cycles with consistent activity and selectivity, the heterogenised system will become practical alternative to the other systems described earlier.

Molecular recognition of geometrical isomers in montmorillonite

Abstractcis-alkenes are hydrogenated preferentially followed by trans-alkenes sequentially from the mixture of geometrical isomers by the montmorillonitebipyridylpalladium(II) acetate catalyst. Such molecular recognition in montmorillonite is unusual and remarkable, and forms an advanced model to enzymes.