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A visible light assisted dearomative selenylative carbo‐spirocyclisation of aromatic homologated‐ynones has been reported. The ynones deliver selenylative spiro‐cyclohexadienones and spiro‐diepoxides at varied temperatures. The prescribed methodology is photo‐catalyst free and scalable. The combination of visible light, molecular oxygen and the products synthesized delivers a uniqueness to the designed methodology.

Selective and controlled oxidation of olefins to aldehydes is a commonly used important transformation in chemistry. However, chemists still use the dangerous and inconvenient ozonolysis method or the less selective, low-yielding Lemieux−Johnson protocol. In a program of developing effective catalysts for this important reaction, we disclose here that an ancillary ligand can play a dramatic role in the above catalytic phenomenon, depending on the design of the ligand precursor chosen. Proof-of-principle is demonstrated with the help of two newly designed [L n Ru II -NHC] precatalysts (NHC = an imidazolydene-based NHC, Im-NHC, or a triazolydene-based NHC, Trz-NHC; L n = para-cymene) for catalytic selective oxidation of olefins/alkynes to carbonyl compounds. With the electron-deficient Trz-NHC ligand, [(para-cymene)Ru II (Im-Trz)] + precatalyst was found to be an order of magnitude more efficient than the [(para-cymene)Ru II (Im-NHC)] + precatalyst.

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In this article, the static and the free vibration behavior of laminated woven glass/epoxy composite plate have been investigated numerically and validated through subsequent experimentation. The laminated composite shear deformable plate has been modelled mathematically using two different higher-order kinematic theories and the commercial finite element package (ANSYS). The domain has been discretized using the finite element steps and the desired responses (deflections and frequencies) are computed numerically using homemade computer code developed in MATLAB environment. The validity and the convergence behavior of developed models have been established by comparing the responses with those available published literature, simulation and the corresponding experiment. Finally, the effects of geometrical and material parameters (thickness ratio, modular ratio and support conditions) and the necessity of higher-order model for the analysis of laminated structure have been highlighted by solving wide variety of static and vibration examples.