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A highly efficient LiBr catalysed regioselective synthesis of vinyl sulfones from readily available terminal epoxides and sodium sulfinates in a one-pot procedure using water as a reaction medium is reported. The protocol is adorned with several attributes of green chemistry like recycling of the catalyst, atom-economy and an aqueous medium.

A metal‐free, convenient photocatalytic approach to chalcones from β‐nitrostyrenes and benzaldehydes via a radical denitrative benzoylation pathway is reported. The salient features of the protocol include the utilization of visible light as an inexpensive and ecosustainable energy source, N‐hydroxyphthalimide (NHPI) as a reusable organophotocatalyst and acetonitrile as an acceptable green solvent to afford chalcones in excellent yields at room temperature in a one‐pot procedure. Notably, this is the first application of β‐nitrostyrenes as readily available substrates for chalcone synthesis and the first example of photocatalysis in this field.magnified image

One-pot montmorillonite K-10 clay supported reactions of either salicylaldehyde/2-hydroxyacetophenone hydrazones and aryl-/alkylureas or salicylaldehydes/2-hydroxyacetophenone and 4-aryl-/alkylsemicarbazides expeditiously yield 3,4-dihydro-4-hydrazino-2H-benz[e]-1,3-oxazin-2-ones (9) via cycloisomerization of the intermediate salicylaldehyde/2-hydroxyacetophenone 4-aryl-/alkylsemicarbazones (5) under solvent-free microwave irradiation. Under the same conditions, hydrazines (9) readily underwent reductive dehydrazination on alumina-supported copper(II) sulfate to furnish 2H-benz[e]-1,3-oxazin-2-ones (10).