In situ Raman spectroscopy and Raman mapping are used to monitor the crystallization of amorphous paracetamol in both covered and uncovered geometries, for which different crystallization pathways have been reported previously. The results suggest that surface crystallization predominates in the uncovered samples, leading to forms I and II, whereas in the covered samples bulk crystallization dominates and leads to form III.

Intermolecular tandem copper-catalyzed O-arylation-oxidative acylation (cross dehydrogenative coupling-CDC) has been developed under air as an oxidant. The reaction between 2,4-dihydro-3H-pyrazol-3-ones and ortho-halo aryl carboxaldehydes furnished the corresponding chromone fused pyrazoles, in a straightforward manner. The synthetic utility of the presented tandem catalysis has been demonstrated with the synthesis of an A-subtype selective adenosine receptor antagonist in only two steps.

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A one-pot process has been developed for preparing alkaloid-like tricyclic skeletons by employing an Ugi reaction, an acid mediated ipso-cyclization and an aza-Michael addition. The transformation is operationally simple and provides products in a diastereo- and regioselective manner with good-to-excellent yields.

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Structural reasons for the melting point variations in isostructural cocrystals of the aripiprazole drug are investigated through combined spectroscopic and diffraction studies.

The first reverse regioselective intermolecular annulation of aryl substituted 2-acetylenic ketones with O-substituted N-hydroxybenzamides or acrylamides followed by tandem cyclization via ruthenium-catalyzed C–H activation, is reported.