Current Organocatalysis最新文献

{"title":"A Novel Baker’s Yeast-Mediated Microwave-Induced Reduction of Racemic 3-Keto-2-Azetidinones: Facile Entry to Optically Active Hydroxy β-Lactam Derivatives","authors":"Aparna Das, R. N. Yadav, B. Banik","doi":"10.2174/2213337209666220126123630","DOIUrl":"https://doi.org/10.2174/2213337209666220126123630","url":null,"abstract":"\u0000\u0000Microwave technology, together with enzymatic catalysis is a nature-friendly chemical synthesis method with low wastage of solvent and good yield of the products.\u0000\u0000\u0000\u0000Enzymes from various microorganisms can be used in the biochemical processes of a wide range of compounds assisted by microwave irradiation\u0000\u0000\u0000\u0000In this work, the microwave-induced reaction of α-keto β-lactams by Baker's yeast in organic solvent was conducted to afford optically active cis and trans-α-hydroxy-β-lactams for the first time.\u0000\u0000\u0000\u0000These hydroxy compounds are the precursors of numerous natural products of medicinal significances.\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49634290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Polymer Supported Proline-Based Organocatalysts in Asymmetric Aldol Reactions: A Review","authors":"Rubina Shajahan, Rithwik Sarang, Anas Saithalavi","doi":"10.2174/2213337209666220112094231","DOIUrl":"https://doi.org/10.2174/2213337209666220112094231","url":null,"abstract":"\u0000\u0000The use of proline-based organocatalysts has acquired significant importance in organic synthesis, especially in enantioselective synthesis. Proline and its derivatives are proven to be quite effective chiral organocatalysts for a variety of transformations including the aldol reaction, which is considered as one of the important C-C bond forming reactions in organic synthesis. The use of chiral organocatalysts has several advantages over its metal-mediated analogues. Subsequently, a large number of highly efficient proline-based organocatalysts including polymer-supported chiral analogues have been identified for aldol reaction. The use of polymer-supported organocatalysts exhibited remarkable stability under the reaction conditions and offered the best results particularly in terms of its recyclability and reusability. These potential benefits along with its economic and green chemistry advantages have led to the search for many polymer-supported proline catalysts. In this review, recent developments in exploring various polymer immobilized proline-based chiral organocatalysts for asymmetric aldol reactions are described.\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2022-01-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44149247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Agro-waste sourced catalyst as an eco-friendly and sustainable approach for Knoevenagel condensation reaction","authors":"Krishnappa B Badiger, S. Khatavi, P. B. Hiremath, Kantharaju Kamanna","doi":"10.2174/2213337209666211222145453","DOIUrl":"https://doi.org/10.2174/2213337209666211222145453","url":null,"abstract":"\u0000\u0000The present work describes an eco-friendly and sustainable approach for the Knoevenagel condensation of an aromatic aldehyde with ethyl cyanoacetate, and salicylaldehyde with Meldrum acid for the synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin (2-oxo-2H-1-benzopyran) derivatives, respectively. The reaction performed under greener catalytic media Water Extract of Watermelon Fruit Peel Ash (WEWFPA) is an eco-friendly protocol derived from the agro-waste feedstock. Various protocols have been reported for the synthesis of Knoevenagel condensation reaction using a hazardous catalyst or/and solvent found toxic to the environment, reaction time longer, poor yield, and required purification of the final product. The present method provides several added advantages of being completely greener, economic, giving high yield, inexpensive catalyst, and the final product isolated in pure form with good yield.\u0000\u0000\u0000\u0000 The objective of the study was to develop a green methodology for the synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives.\u0000\u0000\u0000\u0000The agro-waste based catalyst developed avoids the use of external inorganic/organic base, additives, and solvent-free synthesis of Knoevenagel condensation of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives under rt and microwave irradiation, respectively described. The microwave irradiation condition requires less time for the completion of the reaction and also gave better yield isolation\u0000\u0000\u0000\u0000We have demonstrated WEWFPA as a greener homogenous agro-waste is employed under rt stirring and microwave irradiation for the economic synthesis of ethyl benzylidenecyanoacetate and 3-carboxy coumarin derivatives. The developed method was found robust, non-hazardous and solvent-free with simple work-up gave target product.\u0000\u0000\u0000\u0000In conclusion, we have established an efficient, simple, agro-waste based catalytic approach for the synthesis of ethylbenzylidenecyanoacetate and 3-carboxy coumarin derivatives employing WEWFPA as an efficient catalyst under rt stirring and microwave synthesis, respectively. The method is a greener, economical and eco-friendly approach for the synthesis of Knoevenagel condensation products. The advantages of the present approach are solvent-free, no external metal, chemical base free, short reaction time and isolated product in good to excellent yields. The catalyst is agro-waste derived, which has abundant in natural sources, thus making the present approach a greener one.\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46888113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green Multi-Component Synthesis of Fused heterocyclic derivatives: An atom economic ecofriendly approach for complex molecules","authors":"R. Dhanalakshmi, Gopal Jeya, M. Anbarasu, V. Sivamurugan","doi":"10.2174/2213337209666211221162019","DOIUrl":"https://doi.org/10.2174/2213337209666211221162019","url":null,"abstract":"\u0000\u0000The construction of fused heterocyclic compounds is always fascinating on the strength of their applications as novel pharmaceuticals. Multi-component reactions (MCRs) are atom economical, beneficial, straightforward and ecofriendly approach for synthesis of complex heterocycles in a single step with higher selectivity.\u0000\u0000\u0000\u0000The review mainly focused on the synthesis of fused heterocycles such as pyrimidine - chromene, Pyrrolo - pyrazine, Pyrazolo - pyrimidine, pyran - imidazole and pyrazole- imidazole - pyrimidine, pyran - pyridmidone, pyrrolo - chromene, pyridine-pyrimidinone, fused indole derivatives, furano - pyran along with some simple MCRs discussed, which published in in the period of 2019 and 2020. A table of summary about 50 heterocycles with product, catalysts and cited literature for are given at end.\u0000\u0000\u0000\u0000From this review we understand that MCRs can deliver an effortless access to molecular targets of our interest with wide choice of reactants and their combinations. Thus, the creativity and choice of reactants are pushing the development in MCRs towards more atom economical and eco-friendly approach\u0000\u0000\u0000\u0000Understanding recent trends in the development of MCRs is a requisite for anyone, who wish to synthesise simple and fused heterocycles. By keeping this as primary objective, the present review provides an overview of latest developments in fused heterocyclic synthesis via green multicomponent reactions in the period of 2019 and 2020. \u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":"861 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68186893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-pot access to 2-oxazolines via a Castro-Stephens coupling and intramolecular cyclization","authors":"D. Nighot, A. Jain, Imran Ali, Varun Rawat","doi":"10.2174/2213337208666211213141836","DOIUrl":"https://doi.org/10.2174/2213337208666211213141836","url":null,"abstract":"\u0000\u0000Here, we have reported easy one-pot access to a series of oxazolines using a modified Castro-Stephens coupling protocol. \u0000\u0000\u0000\u0000\u00002-oxazolines have been shown to have significant biological activity and wide-ranging applications in organic chemistry. These properties make oxazolines as heterocyclic compounds of immense importance. \u0000\u0000\u0000\u0000\u0000The objective of this study is to synthesize oxazoline derivatives via an economical and one-pot protocol. \u0000\u0000\u0000\u0000\u0000 2-oxazoline has been synthesized through Cu-powder mediated Castro-Stephens coupling and intramolecular cyclization route. The mechanism involves a rearrangement in which one of the oxygen from the N-acylamino alcohol group is liberated as water and then transferred to alkyne functionality to form 2-oxazoline derivatives. The oxazolines were characterized by NMR, mass, and XRD studies. \u0000\u0000\u0000\u0000\u0000The protocol is economically viable and uses readily available Cu-powder along with DMF for cross-coupling and cyclization steps. \u0000\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44807258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial","authors":"B. Banik","doi":"10.2174/221333720803211109103525","DOIUrl":"https://doi.org/10.2174/221333720803211109103525","url":null,"abstract":"","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42685641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of Dicarboxylic Acid Catalyst Structure on Hydrolysis of Cellulose Model Compound D-Cellobiose in Water","authors":"Harshica Fernando, A. Amarasekara","doi":"10.2174/2213337208666211129090444","DOIUrl":"https://doi.org/10.2174/2213337208666211129090444","url":null,"abstract":"\u0000\u0000Polycarboxylic acids are of interest as simple mimics for cellulase enzyme catalyzed depolymerization of cellulose. In this study, DFT calculations were used to investigate the effect of structure on dicarboxylic acid organo-catalyzed hydrolysis of cellulose model compound D-cellobiose to D-glucose. \u0000\u0000\u0000\u0000\u0000 Binding energy of the complex formed between D-cellobiose and acid (Ebind), as well as glycosidic oxygen to dicarboxylic acid closest acidic H distance were studied as key parameters affecting the turn over frequency of hydrolysis in water. \u0000\u0000\u0000\u0000\u0000 α-D-cellobiose - dicarboxylic acid catalyst down face approach showed high Ebind values for five of the six acids studied; indicating the favorability of down face approach. Maleic, cis-1,2-cyclohexane dicarboxylic, and phthalic acids with the highest catalytic activities showed glycosidic oxygen to dicarboxylic acid acidic H distances 3.5-3.6 Å in the preferred configuration. \u0000\u0000\u0000\u0000\u0000 The high catalytic activities of these acids may be due to the rigid structure, where acid groups are held in a fixed geometry.\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":"1 1","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41418187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Liquid Membranes in Catalysis","authors":"M. Ashraf, M. Mir","doi":"10.2174/2213337208666211118104716","DOIUrl":"https://doi.org/10.2174/2213337208666211118104716","url":null,"abstract":"\u0000\u0000The supported ionic liquid (SIL) membranes have demonstrated huge potential for numerous applications in current separation science and catalysis. Membrane technology allows for separation of complex mixtures of gases, vapours, liquids and /or solids below trivial conditions. Simultaneous chemical transformations can also be achieved in membranes by using catalytically active materials comprising the membrane or embedded catalysts in the custom built membrane reactors. In the present editorial, the remarkable contribution of liquid membranes in catalysis is highlighted. Some recent applications are presented and compared with conventional methods. In addition, SILs and their applications in catalysis, catalytic membranes and recent advances in membrane separation processes are briefly described. \u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44538328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis, Characterization and Biochemical Analysis of Azo-metal complex of Embelin with Second Group Transition Metals","authors":"M. Mir, M. Ashraf","doi":"10.2174/2213337208666211102104240","DOIUrl":"https://doi.org/10.2174/2213337208666211102104240","url":null,"abstract":"\u0000\u0000The objective of the work is to synthesize, characterize and biochemically analyze Azo-metal complex of Embelin with Second Group Transition Metals.\u0000\u0000\u0000\u0000\u0000The genus Embelia is a well-known herb and has considerable importance in the field of pharmaceutical chemistry. The plant species has been used considerably as a traditional medicine in Ayurveda, old Chinese medicine, and Siddha for a long time. The dried berries of this plant, called “vidanga” have boundless biochemical properties, like anthelmintic, carminative, antibacterial, antibiotic, and hypoglycemic.\u0000\u0000\u0000\u0000\u0000Embelin, metal-embelin (EM) and azo-metal-embelin (EAM) complexes were synthesized, analysed for antioxidant and antimicrobial properties.\u0000\u0000\u0000\u0000\u0000 The metal-embelin (EM) complexes and metal-azo-embelin (EAM) complexes were synthesized by pure mixing of embelin, azo-embelin and metals viz, Tc, Ru, Rh, Pd, Ag and Cd. The embelin and EAN complexes were analysed by various spectroscopic techniques, viz, UV-visible, FTIR, NMR, TGA, MS and CHNS analysis.\u0000\u0000\u0000\u0000\u0000The results authenticate the reaction between metals, and bidentate embelin occurs via quinonic and enolic oxygen atoms as [M (Emb) 2 (H2O)] 2H2O and [M (Emb-Azo)2 (H2O)2]. The antioxidant results show that the complexation between metals and compounds decreases the antioxidant potential significantly. In contrast, the antimicrobial activity shows that cobalt and nickel embelin complexes showed more than 74% growth inhibition against the concerned microbes in comparison to embelin alone. \u0000\u0000\u0000\u0000\u0000As the results are taken into consideration, the scavenging property of embelin shows the reduction in power upon complexation with metals and azo-metals. Also, embelin and its associates as metal-embelin and metal-azo-embelin can be used as antioxidant and antimicrobial agents significantly. \u0000\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48897447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Green and Sustainable Technology: Efficient Strategy for Synthesis of Biologically Active Pyrimidine Derivatives","authors":"B. Sahoo, B. R. Kumar, Krishna Chandra Panda, J. Sruti, A. Tiwari, S. Patra","doi":"10.2174/2213337208666211006143134","DOIUrl":"https://doi.org/10.2174/2213337208666211006143134","url":null,"abstract":"\u0000\u0000Green chemistry is also referred as sustainable technology which involves the design, synthesis, processing and use of chemical substances by reducing or eliminating the chemical hazards. This strategy focuses on atom economy, use of safer solvents or chemicals, use of raw materials from renewable resources, consumption of energy and decomposition of the chemical substances to non-toxic material which are eco-friendly. So, this technology is utilized for the sustainable development of novel heterocyclic scaffold like pyrimidine derivatives. Pyrimidine is a six membered heterocyclic aromatic compound with two nitrogen atoms at positions 1 and 3 in the ring system. Among the other heterocyclic compounds, pyrimidine derivatives plays major role due to their diverse promising biological activities such as antimicrobial, antifungal, anti-viral, anti-tubercular, anti-diabetic, anti-hypertensive, anticancer, anthelmintic, antioxidant, anti-epileptic, antipsychotic, anti-anxiety, antimalarial, antihistaminic, anti-parkinsonian, analgesic and anti-inflammatory etc. The various green methods used for synthesis of pyrimidine derivatives include microwave assisted synthesis, ultrasound induced synthesis, ball milling technique, grinding technique, photo-catalysis. These processes enhance the rate of the reaction which leads to high selectivity with improved product yields as compared to the conventional synthetic methods. This review is focused on the green synthesis of biologically active pyrimidine derivatives.\u0000","PeriodicalId":10945,"journal":{"name":"Current Organocatalysis","volume":" ","pages":""},"PeriodicalIF":1.1,"publicationDate":"2021-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48042704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}