K. Bhaskar Reddy

Vanadium(III) chloride catalyzed Biginelli condensation: solution phase library generation of dihydropyrimidin-(2H)-ones

The three component condensation of an aldehyde, a β-keto ester and urea (thiourea) in the presence of a catalytic amount of VCl 3 is disclosed for the solution phase synthesis of dihydropyrimidinones. The ease of synthesis and work-up allowed the parallel synthesis of a 48-membered library of dihydropyrimidinones quickly and efficiently in good yields.

CeCl3·7H2O: a novel reagent for the synthesis of 2-deoxysugars from d-glycals

Abstract d -Glycals react smoothly with a variety of alcohols in a highly stereoselective manner in the presence of the CeCl 3 ·7H 2 O–NaI reagent system in refluxing acetonitrile under neutral conditions to afford the corresponding 2-deoxy-α-glycopyranosides in high yields. In the absence of NaI, the glycals undergo Ferrier rearrangement under the influence of CeCl 3 ·7H 2 O in refluxing acetonitrile to afford the corresponding 2,3-unsaturated hexopyranosides in good yields.

Glaser oxidative coupling in ionic liquids: an improved synthesis of conjugated 1,3-diynes

Terminal alkynes undergo oxidative-coupling smoothly in the presence of the CuCl-TMEDA catalytic system in hydrophobic [bmim]PF6 ionic liquid under aerobic conditions to produce 1,3-diynes in excellent yields under mild conditions. The substrates, alkynes, show enhanced reactivity and selectivity in ionic liquids (ILs). The recovery of the catalyst is facilitated by the hydrophobic nature of the [bmim]PF6 ionic liquid.

Indium-mediated facile cleavage of the t-butoxycarbonyl group from di-t-butylimidodicarbonate

Di-t-butylimidodicarbonates are selectively and efficiently deprotected to the corresponding mono-BOC protected amines in high yields using indium or zinc metal in refluxing methanol. Simple BOC and CBz protected amines are unaffected by these conditions.