B. Kavita

Catalytic C–C Bond Formation Promoted by Mg–Al–O–t-Bu Hydrotalcite

Abstract Mg–Al–O–t-Bu-hydrotalcite catalyst was found to be an efficient, environmentally attractive and selective solid base catalyst for 1,4 Michael addition. Mg–Al–O–t-Bu hydrotalcite is also effective for simple synthesis of α,β-unsaturated esters and nitriles by condensation of the corresponding activated carboxylic esters or nitriles with various aldehydes by Knoevenagel condensation. These reactions proceeded at room temperature at a greater rate in the presence of Mg–Al–O–t-Bu hydrotalcite than in the presence of any of the other catalysts examined.

Layered double hydroxides containing chiral organic guests: synthesis, characterization and application for asymmetric C-C bond-forming reactions

We designed and developed two heterogeneous enantioselective catalysts, LDH-proline and LDH-BINOL, by incorporating chiral organic molecules viz., L-proline and S-BINOL, into layered double hydroxides (LDHs). These catalysts are characterized by IR, UV/vis and TGA analysis. These organo-LDHs have been successfully employed for various asymmetric C–C bond-forming transformations, and the products are obtained with good to excellent yields albeit low enantiomeric excess.

Synthesis of 2-nitroalkanols by MgAlO-t-Bu hydrotalcite

Henry (nitroaldol) reactions were performed with Mg-Al-O-t-Bu hydrotalcite as catalyst in quantitative yields in liquid phase under mild reaction conditions at a faster rate. Exclusive synthesis of 2-nitroalkanols (3) is realised by compatible basic sites of Mg-Al-O-t-Bu hydrotalcite.

Oxidative coupling of 2-naphthols catalysed by clays-supported iron catalysts

Iron pillared clays (Fe-PILC) were compared to Fe-exchanged K10 (Fe-K10) for the oxidative coupling of 2-naphthols to the corresponding binaphthols. Fe-K10 appeared as the most efficient heterogeneous catalyst giving nearly quantitative yields with many naphthols. The highest activity displayed by Fe-K10 is attributed to the easier accessibility of catalytic sites of the clay. The catalyst can be recycled several times with success.

Mg-Al-O-But–Hydrotalcite:. a mild and ecofriendly catalyst for the cyanoethylation of alcohols and thiols†

Mg-Al-O-But–Hydrotalcite is found to be a mild and efficient catalyst for the cyanoethylation of alcohols and thiols in quantitative yields. Exclusive synthesis of 3-alkoxypropionitriles or 3-alkylmercaptopropionitriles is realised by compatible basic sites of Mg-Al-O-But–Hydrotalcite. The present ecofriendly catalytic system is a potential alternative to soluble bases.