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Synthesis of N-methylated tertiary amines by three-component coupling of carbonyl compounds, amines, and methanol following a tandem reductive amination/N-methylation is reported.

2-(N-alkylamino)pyrimidines are important heterocycles widely found in various pharmaceutically important drugs. Here, we have disclosed a new cooperative ruthenium complex catalyzed tandem multicomponent synthesis of 2-(N-alkylamino)pyrimidines directly from guanidine salt and alcohols. The reactions proceeded through the dehydrogenation of alcohols, followed by C C coupling and sequential C N coupling with guanidine and primary alcohol, with the elimination of three equivalents of hydrogen gas. In this work, application of both the acceptorless dehydrogenative coupling (ADC) and borrowing hydrogen (BH) strategies were accomplished in a single reaction. This catalytic method tolerated a wide range of substrates. The viability of the current method was demonstrated by preparative scale synthesis of a few products. A plausible catalytic cycle was proposed based on various control experiments, mechanistic studies and DFT calculations. Remarkably, 42 new 2-(N-alkylamino)pyrimidines were synthesized following this catalytic protocol.

Sericulture is an allied agricultural activity. It is concerned with the production of silk (and its byproducts). The silks produced in sericulture can be widely categorized as Mulberry silks and Non-Mulberry silks (also called Vanya silk meaning wild silks). Mulberry silk is most widely produced and it plays an essential role in the economic growth of the industry. Mulberry silk is obtained by rearing mulberry silkworms (Bombyx mori L). During rearing, they are fed mulberry leaves which are obtained from the mulberry plants; the primary food plant of the silkworm. The mulberry plant is perennial in nature. It belongs to the Moraceae family and the genus Morus with a wide variety of species, viz. Morus alba, Morus nigra, Morus serrata, etc. Mulberry plants are widely distributed all around the world in Tropical, Subtropical, and Temperate regions. It finds its early roots in Southeast Asia. The Mulberry plant falls prey to many diseases caused by various organisms like bacteria, viruses, fungi, and nematodes. The occurrence and severity of the diseases vary with season, varieties, agro-climatic zones, and the cultural practices that are undertaken. These diseases affect the mulberry leaves, stems, and different parts of the plant. Affected plants stop the growth and reduced leaf yield. As well as, these leaves are not suitable for silkworm feeding. This review mainly focuses on infectious diseases (fungal, bacterial, viral, and nematode) of mulberry plants and their management.

An Ir-catalyzed tandem synthesis of various

The long-established practice of using organic solvents in synthetic chemistry is currently becoming a major focus of environmental alarms as many of the chemical wastes are generated in the form of organic solvents. Recently, various alternative solvents have been recognized by the scientific community, including water, ionic liquids, supercritical fluids, glycerol, polyethylene glycol

The synthesis of heterocycles is an emerging area of chemical research considering their high importance in pharmaceuticals, material chemistry, and natural product synthesis. The development of greener methodologies by employing easily available renewable starting materials has been a long thirst for synthetic chemists. Alcohol is an economical and abundantly available greener substrate produced from diverse sustainable resources. The transition metal-catalyzed acceptorless dehydrogenative coupling (ADC) strategy offers the environmentally benign synthesis of numerous N-heterocycles using alcohols, since only water and hydrogen are produced as the eco-friendly by-products. In this review, we have summarized various aspects of homogeneous and heterogeneously catalyzed recent advancements in the synthesis of heterocycles following the ADC approach.

Herein, we demonstrated an efficient protocol for reductive alkylation of azides/nitro compounds via a borrowing hydrogen (BH) method. By following this protocol, selective mono- and dialkylated amines were obtained under mild and solvent-free conditions. A series of control experiments and deuterium-labeling experiments were performed to understand this catalytic process. Mechanistic studies suggested that the Ir(III)-H was the active intermediate in this reaction. KIE study revealed that the breaking of the C-H bond of alcohol might be the rate-limiting step. Notably, this solvent-free strategy disclosed a high TON of around 5600. Based on kinetic studies and control experiments, a metal-ligand cooperative mechanism was proposed.

Functionalization of alcohol is a promising field in synthesis for the possible conservation of fossil-based-feedstocks, since alcohols can be easily obtained from readily available biomass. Despite the widespread advancement, functionalization of alcohols was predominantly studied using precious metal-based catalysts. The utilization of abundant 3d-metals in catalysis is a cost-effective alternative to their higher congeners. In this context, cobalt is a promising entrant owing to its exceptional catalytic activity and selectivity, unique redox behavior, and diverse reaction mechanism than other transition metals. This review features the advancement in cobalt-catalyzed, both homogeneous and heterogeneous, dehydrogenation of alcohols, numerous C C and C N bond formation reactions, synthesis of heterocycles, and other valuable products formation following the borrowing hydrogen (BH) and acceptorless dehydrogenative coupling (ADC) strategy.