We report the preparation of recyclable heterogeneous catalysts, copper-exchanged fluorapatite, and copper-exchanged tert-butoxyapatite by incorporating basic species F-/tBuO- in apatite in situ by coprecipitation and subsequent exchange with Cu(II). These basic copper catalysts catalyzed N-arylation of imidazoles and other heterocycles with chloroarenes and electron-poor fluoroarenes in good to excellent yields. Synthesis and characterization of some of the intermediates of the catalytic cycle gave some insight into the mechanism of the very important organic transformation. The necessity of basic sites for the activation of C-Cl and C-F bonds in the N-arylation of heterocycles with haloarenes is well-established.

N-Arylation of imidazoles and amines with arylboronic acids was accomplished with copper-exchanged fluorapatite (CuFAP) in methanol at room temperature. The products N-arylimidazoles and N-arylamines were isolated in good to excellent yields. A variety of arylboronic acids were converted to the corresponding N-arylimidazoles and N-arylamines, demonstrating the versatility of the reaction.

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Bismuth triflate catalyzed allylation of a variety of aldehydes and aldimines using allyltributylstannane has been presented. The reaction proceeds rapidly and yields corresponding homoallylic alcohols and homoallylic amines in good yields. The bismuth triflate displays manifold activity over the La, Yb, and Sc triflates. The catalyst is reused for allylation of aldehydes and aldimines without significant loss of catalytic activity for four cycles.

One pot synthesis of 2-substituted indolesviaSonogashira coupling (without a copper catalyst) followed by intermolecular cyclization using Pd-PEPPSI-IPentCl.