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Herein, for the first time we have explored the umpolung reactivity of the vinylogous carbon center of diazo arylidene succinimide (DAS) through rhodium catalysis to achieve [2,3]‐Stevens rearrangement of α‐thioether esters. The protocol has successfully demonstrated the distal C−H bond functionalization of the α‐thioether esters. Alongside, the carbenoid reactivity of DAS has also been achieved with Doyle‐Kirmse reaction of allyl/propargyl phenyl sulfides. The protocol proved to be practical to synthesize a wide variety of [2,3]‐Stevens rearrangement products exclusively and the possible side products emanating from Pummerer rearrangement and [1,2]‐Stevens rearrangement were not observed. This catalytic protocol works smoothly in environmentally benign solvent under open air to afford the corresponding desired products with excellent diastereo‐, regio‐ and chemo‐selectivities in good to excellent yields. The protocol also proved to be scalable on gram quantity. [ABSTRACT FROM AUTHOR]

A straightforward and practical method has been developed to access α-substituted glutaric diesters from acrylates and aldehydes using visible light, with Eosin Y facilitating hydrogen atom transfer (HAT) and subsequent Giese-type addition. Also, sunlight has been successfully used as an alternative sustainable light source. The method has also been explored to access substituted 4,5-dihydro-2H-pyridazinones, which have potential biological and industrial applications. Comprehensive mechanistic investigations have been carried out. [ABSTRACT FROM AUTHOR]

The palladium (II) catalyzed direct C3‐(sp2)−H alkenylation of five membered heterocyclic aldehydes has been developed using 3‐aminobutanoic acid as a catalytic transient directing group. A wide range of heterocyclic aldehydes reacted with various acrylates to afford highly site‐selective C3‐alkenylated products. This method features an exclusive E‐selective alkenylation at the C3‐position of heterocyclic aldehydes with a broad substrate scope. The protocol also proved to be useful to construct the mechanochromic luminogen. [ABSTRACT FROM AUTHOR]

[40] Recently, pyrazolone-based MBH carbonates have emerged as versatile precursors to access spiropyrazolone scaffolds. Keywords: annulation; spiropyrazolones; diastereoselectivity; Morita-Baylis-Hillman carbonates; spirooxindoles EN annulation spiropyrazolones diastereoselectivity Morita-Baylis-Hillman carbonates spirooxindoles 1732 1738 7 08/18/23 20230901 NES 230901 Graph The construction of spiro carbocyclic/heterocyclic structures has received enormous attention from synthetic and medicinal-chemistry researchers in recent decades. Under the optimized reaction conditions, the pyrazolone MBH carbonates B 1a b - B c b reacted efficiently with the 3-methyleneoxindoles B 2a b - B v b to afford the corresponding spiropyrazolone oxindole derivatives B 3a b - B x b in good to excellent yields (up to 98%) and with very high diastereoselectivities (dr 99:1) (Scheme 1). [36] Despite these recent advances in synthesizing spiropyrazolone-fused oxindole derivatives, few methods have been described for the synthesis of a spirocyclic molecule bearing three different scaffolds, such as pyrazolone, oxindole, and cyclopentene, in a diastereoselective manner. [Extracted from the article]

The rearrangement of dithiolanes and dithianes to access disulfide‐linked‐dithioesters under visible‐light photoredox catalysis via controlled C−S bond cleavage has been disclosed. Unlike, the usual deprotection of dithioacetals to corresponding aldehydes under the oxidative conditions, we observed unique regioselective oxidative reactivity of five and six membered cyclic dithioacetals to form disulfide‐linked‐dithioesters by exchanging DMAP and imidazole bases. The generality of the protocol has been demonstrated by exploring a wide range of substrates. As an application, in situ generated thiyl radical has been trapped with disulfides to prepare hetero‐disulfides of potential utility. The protocol proved to be practical on gram scale quantity and relied on clean energy source for the transformation. Based on the series of control experiments, cyclic voltammetry and Stern‐Volmer studies the plausible mechanism has been proposed. [ABSTRACT FROM AUTHOR]

Plastics play a significant part in human life and the world we live in. The use of plastics results in detrimental effects on the natural world, which compels us to look for viable replacements. As a result of their enhanced capacity to biodegrade, bioplastics are becoming increasingly important materials. In recent years, there has been a rapid ascent in the utilization of biopolymers in various applications. The objective of this research is to investigate the impact that silica obtained from rice hull ash (RHA) and microcrystalline cellulose (MCC) obtained from groundnut husk have on the properties of bioplastic obtained from wheat gluten and fish scales. The usage of fish scales has been shown to have a positive effect on weight reduction and debasement rates. Microcrystalline cellulose (MCC) is utilized in a wide range of concentrations, and the influence of MCC on bioplastic is researched. The biodegradability tests of bioplastic revealed that the plastic lost 35% of its weight in just 14 days. The experiments that were done to evaluate the chemical stability and tensile strength of the bioplastic indicated that the MCC content has a significant effect in improving the characteristics of the material. [ABSTRACT FROM AUTHOR]

Visible light promoted chemoselective metal free hydrogenation of activated double bond has been achieved via photoredox catalysis. Eosin Y has proved to be an efficient catalyst for the effective reduction of C−C double bonds of alkylidene oxindoles and succinimides under visible light. Commercially viable DIPEA has been employed as a sacrificial electron donor and it's in‐situ generated cationic radical acts as reductant in this transformation. The method proved to be practical as a broad range of substrates containing activated double bond were easily reduced. The method proved to be scalable on a gram quantity and the reduced product has been utilized successfully for the further synthetic application. The systematic and detailed mechanistic studies reveal the oxidative quenching of the photocatalyst by the activated double bond. [ABSTRACT FROM AUTHOR]

The utilization of wind power generation is increasing throughout the world and it is therefore important that these facilities be integrated in the existing generating capacity planning and operating protocols and procedures. This paper presents an approach to evaluate the contribution that wind power can make to the load carrying capability of a power generating system in an operating scenario. The basic concepts of unit commitment risk analysis are extended to include the inherent variability associated with wind power by developing short-term probability distributions of the wind speed and wind power output using auto-regressive moving average (ARMA) time series models. The operating capacity contributions attributable to wind power are illustrated by application to a small test system and are expressed in terms of the increased load carrying capability due to the wind power generating facilities. Index Terms--Load carrying capability, operating capacity, risk assessment, wind power probability models.