9-(1H-indol-3-yl)-5-methoxy-3,3- dimethyl-2,3,4,9-tetrahydro-1H-xanthen-1-one

• 

  
  Green Chem., 2016, Advance Article
  DOI: 10.1039/C6GC00137H, Paper

  Someshwar D. Dindulkar, Daham Jeong, Eunae Cho, Dongjin Kim, Seunho Jung
  A novel biosourced saccharide catalyst, microbial cyclosophoraose, a cyclic [small beta]-(1,2) glucan, was used for the synthesis of indolyl 4H-chromenes via a one pot three-component Knoevenagel-Michael addition-cyclization reaction in water under neutral conditions.

Microbial cyclosophoraose as a catalyst for the synthesis of diversified indolyl 4H-chromenes via one-pot three component reactions in water

 http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00137H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Microbial cyclosophoraose as a catalyst for the synthesis of diversified indolyl 4H-chromenes via one-pot three component reactions in water

Someshwar D. Dindulkar,^a   Daham Jeong,^a   Eunae Cho,^a  Dongjin Kim^b and   Seunho Jung*^ac  

*

Corresponding authors

^a

Institute for Ubiquitous Information Technology and Applications (UBITA) & Center for Biotechnology Research in UBITA (CBRU), Konkuk University, Seoul 143-701, South Korea 
E-mail: shjung@konkuk.ac.kr

^b

Nelson Mandela African Institution of Science and Technology, PO box 447, Arusha, Tanzania

^c

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, Seoul 143-701, South Korea

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00137H

 As a novel biosourced saccharide catalyst, microbial cyclosophoraose, a cyclic β-(1,2) glucan, was used for the synthesis of therapeutically important versatile indolyl 4H-chromenes via a one pot three-component Knoevenagel–Michael addition–cyclization reaction of salicylaldehyde, 1,3-cyclohexanedione/dimedone, and indoles in water under neutral conditions. A possible reaction mechanism through molecular complexation is suggested based on 2D ROESY NMR spectroscopic analysis. Moreover, green chemistry metric calculations were carried out for a model reaction, indicating the satisfactory greener approach of this method, with a low E-factor (0.18) and high atom economy (AE = 91.20%). The key features of this protocol are based on two critical factors where the first is to use a novel eco-friendly supramolecular carbohydrate catalyst and the second is its fine green properties such as compatibility with various substituted reactants, recyclability of the catalyst, chromatography-free purification, high product selectivity, and clean conversion with moderate to excellent yields in an aqueous medium.

 9-(1H-indol-3-yl)-5-methoxy-3,3- dimethyl-2,3,4,9-tetrahydro-1H-xanthen-1-one (4a):

 (2-hydroxy-3-methoxybenzaldehyde 1, Dimedone 2

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Microbial cyclosophoraose as a catalyst for the synthesis of diversified indolyl 4H-chromenes via one-pot three component reactions in water

• 

  
  Green Chem., 2016, Advance Article
  DOI: 10.1039/C6GC00137H, Paper

  Someshwar D. Dindulkar, Daham Jeong, Eunae Cho, Dongjin Kim, Seunho Jung
  A novel biosourced saccharide catalyst, microbial cyclosophoraose, a cyclic [small beta]-(1,2) glucan, was used for the synthesis of indolyl 4H-chromenes via a one pot three-component Knoevenagel-Michael addition-cyclization reaction in water under neutral conditions.

Microbial cyclosophoraose as a catalyst for the synthesis of diversified indolyl 4H-chromenes via one-pot three component reactions in water

 http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00137H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Microbial cyclosophoraose as a catalyst for the synthesis of diversified indolyl 4H-chromenes via one-pot three component reactions in water

Someshwar D. Dindulkar,^a   Daham Jeong,^a   Eunae Cho,^a  Dongjin Kim^b and   Seunho Jung*^ac  

*

Corresponding authors

^a

Institute for Ubiquitous Information Technology and Applications (UBITA) & Center for Biotechnology Research in UBITA (CBRU), Konkuk University, Seoul 143-701, South Korea 
E-mail: shjung@konkuk.ac.kr

^b

Nelson Mandela African Institution of Science and Technology, PO box 447, Arusha, Tanzania

^c

Department of Bioscience and Biotechnology, Microbial Carbohydrate Resource Bank (MCRB), Konkuk University, Seoul 143-701, South Korea

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00137H

 As a novel biosourced saccharide catalyst, microbial cyclosophoraose, a cyclic β-(1,2) glucan, was used for the synthesis of therapeutically important versatile indolyl 4H-chromenes via a one pot three-component Knoevenagel–Michael addition–cyclization reaction of salicylaldehyde, 1,3-cyclohexanedione/dimedone, and indoles in water under neutral conditions. A possible reaction mechanism through molecular complexation is suggested based on 2D ROESY NMR spectroscopic analysis. Moreover, green chemistry metric calculations were carried out for a model reaction, indicating the satisfactory greener approach of this method, with a low E-factor (0.18) and high atom economy (AE = 91.20%). The key features of this protocol are based on two critical factors where the first is to use a novel eco-friendly supramolecular carbohydrate catalyst and the second is its fine green properties such as compatibility with various substituted reactants, recyclability of the catalyst, chromatography-free purification, high product selectivity, and clean conversion with moderate to excellent yields in an aqueous medium.

 9-(1H-indol-3-yl)-5-methoxy-3,3- dimethyl-2,3,4,9-tetrahydro-1H-xanthen-1-one (4a):

 (2-hydroxy-3-methoxybenzaldehyde 1, Dimedone 2

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Probing the mechanism of benzaldehyde reduction to chiral hydrobenzoin on the CNT surface under near-UV light irradiation

Green Chem., 2016, 18,1482-1487
DOI: 10.1039/C5GC02168E, Paper

Yunwei Wang, Pengju Ren, Xianmo Gu, Xiaodong Wen, Yingyong Wang, Xiangyun Guo, Eric R. Waclawik, Huaiyong Zhu, Zhanfeng Zheng
For the first time, metal-free CNTs is found to be an effective photocatalyst working under near-UV light (400 nm)

Probing the mechanism of benzaldehyde reduction to chiral hydrobenzoin on the CNT surface under near-UV light irradiation

Yunwei Wang,^a   Pengju Ren,^ab   Xianmo Gu,^a   Xiaodong Wen,^ab  Yingyong Wang,^a   Xiangyun Guo,^a   Eric R. Waclawik,^c  Huaiyong Zhu^c and   Zhanfeng Zheng*^a  

*

Corresponding authors

^a

State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, CAS, Taiyuan, China
E-mail: zfzheng@sxicc.ac.cn
Fax: +86-351-4040605

^b

National Energy Center for Coal to Liquids, Synfuels China Co., Ltd, Huairou District, Beijing, China

^c

School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, Australia

Green Chem., 2016,18, 1482-1487

DOI: 10.1039/C5GC02168E
Received 13 Sep 2015, Accepted 21 Dec 2015

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC02168E?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract



Metal-free CNTs exhibit high activity (conversion rate 99.6%, 6 h) towards the synthesis of chiral hydrobenzoin from benzaldehyde under near-UV light irradiation (320–400 nm). The CNT structure before and after the reaction, the interaction between the molecule and the CNT surface, the intermediate products, the substitution effect and the influence of light on the reaction were examined using various techniques. A photo-excited conduction electron transfer (PECET) mechanism for the photocatalytic reduction using CNTs has been proposed. This finding provides a green photocatalytic route for the production of hydrobenzoin and highlights a potential photocatalytic application of CNTs.






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Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

Green Chem., 2016, Advance Article
DOI: 10.1039/C5GC03102H, Paper

L. Puchot, P. Verge, T. Fouquet, C. Vancaeyzeele, F. Vidal, Y. Habibi
Asymmetric di-benzoxazine monomers from naturally occurring phenolic compounds - cardanol and vanillin - were synthesized to obtain a processable and self-supported bio-thermoset with valuable properties. Such strategy constitutes an efficient and versatile route for the elaboration of biobased thermoset from a wide range of phenolic compounds derived from renewable resources.

Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC03102H?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

With the ongoing efforts to promote the development of bio-based dibenzoxazine thermosets, we explore herein a new strategy aiming at the synthesis of asymmetric dibenzoxazine monomers from naturally occurring phenolic compounds, cardanol and vanillin. By taking advantage of the low reactivity of cardanol, a monosubstituted cardanol-based benzoxazine monomer was prepared and further coupled with vanillin to yield vanillin–cardanol di-benzoxazines. The structural features of the resulting products were substantiated by ¹H NMR and HR-MS. The occurrence of the thermally-induced ring-opening polymerization was monitored by rheological measurements and DSC. At 190 °C the new asymmetric monomers showed a moderate gelation time (8 min) compared to 30–31 min revealed for cardanol-based (di-card) dibenzoxazines. Once polymerized, they exhibited a high T_g (129 °C), while the di-card flew under heating because of its low cross-linking density. Asymmetric monomers also exhibited lower melting temperatures than their symmetrical congeners based on vanillin, which significantly enlarge the processing window between the melting and polymerization temperatures up to 126 °C instead of 7 °C for symmetric vanillin-based dibenzoxazines. Therefore, such a strategy constitutes an efficient and versatile route for an easy elaboration of biobased monocomponent thermosets and can be applied to a wide range of phenolic compounds derived from renewable resources.

Breaking the symmetry of dibenzoxazines: a paradigm to tailor the design of bio-based thermosets

L. Puchot,^ab   P. Verge,*^a   T. Fouquet,^c   C. Vancaeyzeele,^b  F. Vidal^b and   Y. Habibi*^a  

*

Corresponding authors

^a

Luxembourg Institute of Science and Technology (LIST), 5 avenue des Hauts-Fourneaux, L-4362 Esch-sur-Alzette, Luxembourg 
E-mail: Pierre.verge@list.lu, Youssef.habibi@list.lu

^b

Laboratoire de Physicochimie des Polymères et des Interfaces (LPPI – EA 2528), I-Mat, Université de Cergy-Pontoise, 5 mail Gay-Lussac, 95031 Cergy-Pontoise, France

^c

Environmental Measurement Technology Group, Environmental Management and Research Institute (EMRI), National Institute of Advanced Industrial Science and Technology (AIST), Onogawa 16-1, Tsukuba, Japan

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC03102H  //////////

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A broadly applicable catalyst system consisting of water-soluble Pd–imidate complexes has been enployed for the Suzuki–Miyaura cross-coupling of four different nucleosides in water under mild conditions. The efficient nature of the catalyst system also allowed its application in developing a microwave-assisted protocol with the purpose of expediting the catalytic reaction. Preliminary mechanistic studies, assisted by catalyst poison tests and stoichiometric tests performed using an electrospray ionization spectrometer, revealed the possible presence of a homotopic catalyst system.

 

Water-Soluble Pd–Imidate Complexes: Broadly Applicable Catalysts for the Synthesis of Chemically Modified Nucleosides via Pd-Catalyzed Cross-Coupling

Vijay Gayakhe^†, Ajaykumar Ardhapure^†, Anant R. Kapdi^*†, Yogesh S. Sanghvi^‡, Jose Luis Serrano^§, Luis García^§, Jose Pérez^§, Joaquím García^∥, Gregorio Sánchez^∥, Christian Fischer^⊥, and Carola Schulzke^⊥

^† Institute of Chemical Technology, Mumbai Nathalal Road, Matunga, Mumbai 400019, India

^‡ Rasayan, Inc. 2802 Crystal Ridge Road, Encinitas, California 92024-6615, United States

^§ Departamento de Ingeniería Minera, Geológica y Cartográfica, Universidad Politécnica de Cartagena, Área de Química Inorgánica, Regional Campus of International Excellence “Campus Mare Nostrum”, Universidad Politécnica de Cartagena, 30203 Cartagena, Spain

^∥ Departamento de Química Inorgánica, Regional Campus of International Excellence “Campus Mare Nostrum”, Universidad de Murcia, 30071 Murcia, Spain

^⊥ Ernst-Moritz-Arndt-Universität Greifswald, Institut für Biochemie, Felix-Hausdorff-Strasse 4, 17489 Greifswald, Germany

J. Org. Chem., Article ASAP

DOI: 10.1021/acs.joc.5b02475

Publication Date (Web): February 27, 2016

Copyright © 2016 American Chemical Society

*E-mail: ar.kapdi@ictmumbai.edu.in.

 http://pubs.acs.org/doi/abs/10.1021/acs.joc.5b02475

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Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Green Chem., 2016, Advance Article
DOI: 10.1039/C6GC00384B, Paper

Daolai Sun, Eisyun Kitamura, Yasuhiro Yamada, Satoshi Sato
Nitriles were efficiently produced in a vapor-phase dehydration of aldoximes over SiO₂ catalysts without external heat supply.

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C6GC00384B?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

 

A vapor-phase dehydration of acetaldoxime to acetonitrile was investigated over various solid catalysts. Among the tested catalysts, ZrO₂, Al₂O₃ and SiO₂ showed high catalytic activity for the formation of acetonitrile from acetaldoxime, while the correlation between catalytic activity and the acid property of the catalysts was not observed. Weak acidic sites such as silanols sufficiently work as catalytic sites for the dehydration, which does not require strong acids such as zeolites. Several SiO₂ catalysts with different physical properties were tested, and the SiO₂with the smallest pore size and the highest specific surface area showed the highest catalytic activity for the formation of acetonitrile. Because the dehydration of acetaldoxime to acetonitrile is exothermic, a large amount of reaction heat was generated during the reaction, and the reaction temperature was found to be significantly affected by the feed rate of the reactant and the flow rate of the carrier gas. In order to effectively utilize the in situ generated reaction heat, the dehydration of acetaldoxime to acetonitrile without using the external heat supply was conducted. The temperature was controllable even in the absence of the external heat, and the acetonitrile yield higher than 90% could be achieved in such a green operation under the environment-friendly adiabatic conditions.

 

 

Efficient formation of nitriles in the vapor-phase catalytic dehydration of aldoximes

Daolai Sun,^a   Eisyun Kitamura,^a   Yasuhiro Yamada^a and  Satoshi Sato*^a  

*Corresponding authors

^aGraduate School of Engineering, Chiba University, Chiba, Japan
E-mail: satoshi@faculty.chiba-u.jp
Fax: +81 43 290 3401
Tel: +81 43 290 3377

Green Chem., 2016, Advance Article

DOI: 10.1039/C6GC00384B

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Nanopalladium-catalyzed conjugate reduction of Michael acceptors - application in flow

Nanopalladium-catalyzed conjugate reduction of Michael acceptors - application in flow

 

Green Chem., 2016, Advance Article
DOI: 10.1039/C5GC02920A, Communication

Anuja Nagendiran, Henrik Sorensen, Magnus J. Johansson, Cheuk-Wai Tai, Jan-E. Backvall
A continuous-flow approach towards the selective nanopalladium-catalyzed hydrogenation of the olefinic bond in various Michael acceptors, which could lead to a greener and more sustainable process, has been developed.

 

A continuous-flow approach towards the selective nanopalladium-catalyzed hydrogenation of the olefinic bond in various Michael acceptors, which could lead to a greener and more sustainable process, has been developed. The nanopalladium is supported on aminofunctionalized mesocellular foam. Both aromatic and aliphatic substrates, covering a variation of functional groups such as acids, aldehydes, esters, ketones, and nitriles were selectively hydrogenated in high to excellent yields using two different flow-devices (H-Cube® and Vapourtec). The catalyst was able to hydrogenate cinnamaldehyde continuously for 24 h (in total hydrogenating 19 g cinnanmaldehyde using 70 mg of catalyst in the H-cube®) without showing any significant decrease in activity or selectivity. Furthermore, the metal leaching of the catalyst was found to be very low (ppb amounts) in the two flow devices

 

 

3 Gottlieb, H. E.; Kotlyar, V; Nudelman, A. J. Org. Chem. 1997, 62, 7512-7515.

 

 

Nanopalladium-catalyzed conjugate reduction of Michael acceptors – application in flow

Anuja Nagendiran,^ab   Henrik Sörensen,^bc  Magnus J. Johansson,^bc   Cheuk-Wai Tai^d and  Jan-E. Bäckvall*^ab  

*Corresponding authors

^aDepartment of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
E-mail: jeb@organ.su.se

^bBerzelii Centre EXSELENT on Porous Materials, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden

^cAstraZeneca R&D, Innovative Medicines, Cardiovascular and Metabolic Disorders, Medicinal Chemistry, Pepparedsleden 1, SE-431 83 Mölndal, Sweden

^dDepartment of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91, Stockholm, Sweden

Green Chem., 2016, Advance Article

DOI: 10.1039/C5GC02920A

http://pubs.rsc.org/en/Content/ArticleLanding/2016/GC/C5GC02920A?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

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