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A new oxygen bridged [Cu‐O‐Ba] bimetallic catalyst is synthesized. The novel catalyst is used for Csp2‐O cross‐coupling reactions of phenols with haloarenes. Iodo‐, bromo‐, and unactivated chloro‐arenes could be coupled with aryl phenols efficiently in high yield. Moreover, functional groups were well tolerated using this protocol. The catalyst is Eco‐friendly, air stable, recyclable and efficient. [ABSTRACT FROM AUTHOR]

Formation of carbon‐selenium bond by Csp2‐Se cross‐coupling using diaryldiselenides and arylhalides are very few in literature. Herein we report CuSeO3.2H2O as an efficient catalyst for direct Csp2‐Se cross‐coupling of diaryldiselenides with aryl iodides, bromides and aryl boronic acids. The reaction is performed at low temperature (70 °C) in tert‐butanol solvent in absence of ligand. Arylboronic acids are more reactive than aryliodides and bromides. [ABSTRACT FROM AUTHOR]

In this work, an oxo‐bridged bimetallic CuMoO4 catalyst for Csp2−Se cross‐coupling of diaryldiselenides with aryl‐halides is reported. The current discovery is noteworthy, as the catalyst is eco‐friendly, easily accessible, air‐stable, and recyclable. The methodology exhibits broad substrate scope and the catalytic system tolerates common functional groups. The protocol uses aryl iodide and bromides as electrophile instead of boronic acids. This is the first example of using an oxo‐ bridged copper based bimetallic catalyst for Csp2−Se cross‐coupling reactions in water. C−Cl bond remains intact during reaction. [ABSTRACT FROM AUTHOR]

Transition metal catalysed formation of Csp2‐S bond through cross‐coupling reaction stands important and powerful tools in synthetic organic chemistry. The reaction constitutes an important strategy for the synthesis of thioethers that possess diverse biological activities in medicine and agriculture. Nonetheless, maintaining reaction temperature during Csp2‐S cross‐coupling reaction decides fate of desired product along with possibility of by‐product and disulfides. The economy of process, safety and environmental issue demands thioether synthesis at mild condition and room temperature. Only very few reactions were successful under mild condition using Pd, Cu, Ni, Ni−Ir and Ir catalyst. The current prospective summarizes the best protocols used for efficient Csp2‐S cross‐coupling reactions by transition metal catalyst under mild condition. [ABSTRACT FROM AUTHOR]

Though concept of oxygen bridged bimetallic catalyst for organic reaction is not well understood. Herein, we have tried to explain the concept by experimental as well as its support by full DFT study. We report here a competent protocol for dehydrogenative oxidation of benzylic alcohol using an oxygen bridged bimetallic CuMoO4 nano catalyst. Careful demonstration reveals that oxidation is not effective either with mono‐metallic Cu (II) or Mo(VI); instead combination of both the metals through the oxygen bridge [Cu−O−Mo] unexpectedly and interestingly catalyzed the reaction efficiently. The new concept is strongly supported by computational DFT study. DFT study reveals dehydrogenative oxidation is preferred at copper centre over molybdenum and aromatic benzyl alcohols are greatly stabilised. Interaction barrier energy of monometallic CuO and MoO3 catalyst is much higher than bimetallic CuMoO4. Hydrogen transfer has larger barrier heights for CuO (31.5 kcal/mol) and MoO3 (40.3 kcal/mol) than bimetallic CuMoO4. [ABSTRACT FROM AUTHOR]

Presence of multi‐stereo centre in the antimalaria artemisinin molecules makes difficult to chemist for diastereoselective synthesis. This diastereoselectivity is the main hurdle for low yield of product in the reported synthesis. Though, artemisinin‐based drugs are in the frontline treatment of malaria and effective medicine that kills malarial parasites. Due to insufficient production of artemisinin (qinghaosu), millions of people lost their lives in past years worldwide. The current review will summarize the strategy developed so far for synthesis of antimalaria artemisinin and problems encountered during the synthesis. The combined insight of different methods may allow finer approaches capable of delivering efficient synthetic approaches for developing artemisinin and their hybrid analogues for further drug discovery. [ABSTRACT FROM AUTHOR]

CuII catalyst is less efficient at room temperature for C−S cross‐coupling. C−S cross‐coupling by CuII catalyst at room temperature is not reported; however, doping of copper with molybdenum metal has been realized here to be more efficient for C−S cross‐coupling in comparison to general CuII catalyst. The doped catalyst CuMoO4 nanoparticle is found to be more efficient than copper. The catalyst works under mild conditions without any ligand at room temperature and is recyclable and effective for a wide range of thiols and haloarenes (ArI, ArBr, ArF) from milligram to gram scale. The copper‐based bimetallic catalyst is developed and recognized for C−S cross‐coupling of haloarenes with alkyl and aryl thiols. [ABSTRACT FROM AUTHOR]

The reaction of cotarnine and acyl/aryl ketones in "green" solvents provides an efficient approach to an array of privileged 1,2,3,4-tetrahydroisoquinolines in excellent yields by metal-free activation of C(sp³)-H bonds. This one-pot procedure takes place under base-free conditions at room temperature, and tolerates a wide range of functionalities. The reaction is highly chemoselective, can be performed on a multi-gram scale, and pure products are isolated by simple filtration without workup. Interestingly, the complementary two-step procedure from cotarnine halide salts gives the Mannich products in good yields. The scope was elaborated to 9-bromocotarnine salts to access a range of 9-bromonoscapine-derived analogues. The methodology has been developed considering the structural similarity of cotarnine derivatives to noscapinoids, which represent an emerging class of microtubule-modulating anticancer agents. [ABSTRACT FROM AUTHOR]

C(sp)−H Bond activation of acetylene molecule still remains a challenge for synthetic organic chemists. In practice, acetylenes are activated by strong bases and metals. The first example for activating acetylenic protons under base and metal-free conditions is reported here. It involves a general method for synthesizing propargylic derivatives of cotarnine. An array of tetrahydroisoquinolines alkaloids was synthesized by C(sp)−H bond activation of aromatic acetylenes with cotarnine at room temperature. A DFT-based mechanism is proposed for the reaction. [ABSTRACT FROM AUTHOR]