Metal-free oxidative cyclization of 2-aminobenzothiazoles and cyclic ketones enabled by the combination of elemental sulfur and oxygen

Metal-free oxidative cyclization of 2-aminobenzothiazoles and cyclic ketones enabled by the combination of elemental sulfur and oxygen

Green Chem., 2017, Advance Article
DOI: 10.1039/C7GC02014G, Communication

Yanjun Xie, Xiangui Chen, Zhen Wang, Huawen Huang, Bing Yi, Guo-Jun Deng
Aerobic cyclization of 2-aminobenzothiazoles and cyclic ketones enabled by the combination of elemental sulfur and oxygen under metal-free conditions.

Metal-free oxidative cyclization of 2-aminobenzothiazoles and cyclic ketones enabled by the combination of elemental sulfur and oxygen

Yanjun Xie,^ab  Xiangui Chen,^a  Zhen Wang,^a  Huawen Huang,*^a  Bing Yi*^b  and  Guo-Jun Deng*^a 

*Corresponding authors

^aKey Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education, College of Chemistry, Xiangtan University, Xiangtan 411105, China
E-mail: hwhuang@xtu.edu.cn, gjdeng@xtu.edu.cn
Fax: (+86)0731-5829-2251
Tel: (+86)0731-5829-8601

^bCollege of Chemistry and Chemical Engineering, Hunan Institute of Engineering, Xiangtan 411104, China
E-mail: bingyi2004@126.com

http://pubs.rsc.org/en/Content/ArticleLanding/2017/GC/C7GC02014G?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+rss%2FGC+%28RSC+-+Green+Chem.+latest+articles%29#!divAbstract

Abstract

Metal-free oxidative cyclization for the one-pot synthesis of benzo[d]imidazo[2,1-b]thiazoles from 2-aminobenzothiazoles and cyclic ketones is described. Elemental sulfur combined with molecular oxygen as the benign co-oxidant was found to be unique and highly effective to promote this transformation without the aid of any metal salts. Various cyclic ketones smoothly reacted with 2-aminobenzothiazoles to give functional benzo[d]imidazo[2,1-b]thiazoles in good to very high yields, which thereby demonstrated the synthetic convergence of this methodology.

 

 

7,8,9,10-Tetrahydrobenzo[d]benzo[4,5]imidazo[2,1-b]thiazole (3a)

White solid; yield: 39.2 mg (86%), mp 140-142 °C.

 

1H NMR (400 MHz, CDCl3, ppm) δ 7.67-7.62 (m, 2H), 7.38 (t, J = 7.76 Hz, 1H), 7.27 (t, J = 7.68 Hz, 1H), 3.07-3.04 (m, 2H), 2.77-2.74 (m, 2H), 2.00-1.95 (m, 2H), 1.92-1.86 (m, 2H);

 

13C NMR (100 MHz, CDCl3, ppm) δ 145.1, 142.4, 132.9, 129.7, 125.5, 123.9, 123.5, 121.8, 111.9, 24.8, 22.8, 22.7, 21.8;

 

MS (EI) m/z (%) 228, 200 (100), 160, 108, 51;

 

HRMS calcd. for: C13H13N2S + (M+H)+ 229.07940, found 229.07941.

 

 

 

 

 

PREDICT

 

 

cas 325766-28-7

C₁₃ H₁₂ N₂ S, 228.31,  Benzimidazo[2,​1-​b]​benzothiazole, 7,​8,​9,​10-​tetrahydro-

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C1CCCc2c1nc3sc4ccccc4n23

Selective reductive amination of aldehydes from nitro compounds catalyzed by molybdenum sulfide clusters

Selective reductive amination of aldehydes from nitro compounds catalyzed by molybdenum sulfide clusters

Green Chem., 2017, Advance Article
DOI: 10.1039/C7GC01603D, Communication

 Open Access

  This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.

E. Pedrajas, I. Sorribes, K. Junge, M. Beller, R. Llusar

A one-pot selective synthesis of secondary amines catalyzed by a well-defined Mo3S4 cluster using hydrogen as a benign reductant

Selective reductive amination of aldehydes from nitro compounds catalyzed by molybdenum sulfide cluste

E. Pedrajas,a  I. Sorribes,b  K. Junge,b  M. Beller*b  and  R. Llusar*a 

*Corresponding authors

aDepartament de Química Física i Analítica, Universitat Jaume I, Av. Sos Baynat s/n, 12071 Castelló, Spain
E-mail:rosa.llusar@uji.es

bLeibniz-Institute für Katalyse e. V. an der Universität Rostock, Albert Einstein Str. 29a, 18059 Rostock, Germany

 Prof. Dr. Matthias Beller (matthias.beller@catalysis.de),

LLUSAR BARELLES, ROSA MARÍA Catedràtic/a d'Universitat Miembro del Claustro Miembro del Consejo de Gobierno Materiales Moleculares TC1221DD - (964 728086) llusar@uji.es  Prof. Dr. Rosa Llusar (rosa.llusar@uji.es)

Reseña Personal

Rosa Llusar Barelles nace en Almenara (Castellón). En 1983 se licencia en Químicas por la Universidad de Valencia obteniendo el premio extraordinario de licenciatura. Su investigación doctoral se centra en la química de sulfuros de molibdeno y wolframio y se doctora por la Universidad de Valencia en 1987 y por la Universidad de Texas A&M (EE. UU) en 1988 bajo la dirección del profesor F. Albert Cotton. Después de trabajar durante tres años como técnico superior en la sección de investigación y desarrollo de una planta de producción de caprolactama en Castellón, realiza una estancia posdoctoral de un año (1992) con el profesor John D. Corbett en el Ames Laboratory (Iowa State University, EE. UU) investigando nuevas fases sólidas de haluros reducidos de tierras raras. En 1993 accede a una plaza de profesora interina en el Departamento de Ciencias Experimentales de la Universidad Jaume I de Castellón, en 1995 pasa a ser profesora Titular de Química Física y en 2009 Catedrática de Universidad.  Desde entonces ha desarrollado su actividad docente en la licenciatura y ahora grado en Química dentro del ámbito de la química física (cuántica, espectroscopia, termodinámica, cinética, electroquímica etc.). Actualmente imparte la asignatura de “nanomateriales” en el máster en Química Aplicada y Farmacológica de la Universitat Jaume I. Ha sido profesora visitante en la Universidad Católica de Valparaíso (Chile), Universidad de Angers (Francia), la Universidad de Rennes (Francia) y en la Universidad Estadual Paulista (Brasil) en 2015.

La Prof. Llusar lidera desde su creación en 1998, el grupo de investigación de materiales moleculares de la Universitat Jaume I (http://www.grupo-rllusar.uji.es/). Su investigación está centrada en la química de clústeres metálicos con especial énfasis en sus propiedades fisicoquímicas de cara al desarrollo de nuevos materiales moleculares multifuncionales con aplicaciones de interés tecnológico en catálisis, electrónica molecular y medicina. Hasta la fecha, la Prof. Llusar ha dirigido diez tesis doctorales, seis de ellas con mención de doctorado europeo o internacional y una sexta realizada en cotutela y defendida en la Universidad Central de Venezuela. Es coautora de más de ciento cincuenta artículos en revistas científicas internacionales indexadas. El Instituto Nikolaev perteneciente a la Academia Rusa de las Ciencias ha reconocido su labor investigadora y de cooperación otorgándole en junio de 2012 el título de Doctora “Honoris Causa”. El Consejo Social de la Universitat Jaume I la galardonó en 2015 con el XVII Premio a la Trayectoria Investigadora.

En el ámbito de la gestión universitaria ha ejercido como vicerrectora de investigación de la Universitat Jaume I desde junio de 2006 durante cuatro años y como directora de los Servicios Centrales de Investigación Científica desde junio de 2010 hasta septiembre de 2014. En la actualidad es miembro del Claustro y del Consejo de Gobierno de la esta Universidad.

Links

• Página web del grupo de materials moleculars

Rosa Llusar

 

pedrajas@uji.es

Elena Pedrajas Gual

Biodata

Elena Pedrajas Gual is a PhD student in the Molecular Materials Group with a Predoctoral fellowship granted by the University Jaume I in April 2013. Previously, she was licensed in Chemistry in the same university and she studied the Master of Applied and Pharmacologic Chemistry, in the specialty of Advanced Materials. She also was granted with another fellowship by the university and a collaboration fellowship by the Spanish Ministry of Education, which were both developed in the same research group.

She is a member of the Molecular Materials Group since 2012, and her line of research is focused in the synthesis and characterization of M3S4 and M3M'S4 clusters (M= Mo, W and M'= transition metal) functionalized with nitrogen donor ligands. Later, the reactivity of the new clusters is studied and also their catalytic activity in industrial processes of interest.

She is the author of an article published in the journal of catalysis ChemCatChem during the year 2015, and she has presented her results in both national and international conferences. She has participated in different research projects of Spanish Ministry, Valencian Community and University Jaume I. She did a temporary stay during two months in the "Leibniz-Institüt für Katalyse" in Rostock (Germany), under the supervision of Professor Matthias Beller.

Her teaching career will start during the academic year 2015-2016 with the course Physical Chemistry IV in the Bachelor's Degree in Chemistry, which consist of an introduction to the basic principles of spectroscopy

Abstract

Secondary amines are selectively obtained from low value starting materials using hydrogen and a non-noble metal-based catalyst. The reductive amination of aldehydes from nitroarenes or nitroalkanes is efficiently catalyzed by a well-defined diamino molybdenum sulfide cluster in a one-pot homogeneous reaction. The integrity of the molecular cluster catalyst is preserved along the process.

N-(4’-Methoxybenzyl)aniline3 :

1H NMR (300 MHz, CDCl3) δ 7.26 (d, J = 8.6 Hz, 2H), 7.21 – 7.11 (m, 2H), 6.86 (d, J = 8.7 Hz, 2H), 6.69 (t, J = 7.3 Hz, 1H), 6.64 – 6.58 (m, 1H), 4.22 (s, 2H), 3.92 (br s, 1H), 3.77 (s, 3H);

13C NMR (75 MHz, CDCl3) δ 158.96, 148.32, 131.53, 129.35, 128.90, 117.59, 114.13, 112.94, 55.39, 47.89;

MS (EI): m/z (rel. Int) 213.

1H AND 13C NMR PREDICTIONS

CLICK OM IMAGE FOR CLEAR VIEW

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Polymers from biomass: one pot two-step synthesis of furilydenepropanenitrile derivatives with MIL-100(Fe) catalyst

 

Polymers from biomass: one pot two-step synthesis of furilydenepropanenitrile derivatives with MIL-100(Fe) catalyst

Catal. Sci. Technol., 2017, 7,3008-3016
DOI: 10.1039/C7CY00463J, Paper

Anastasia Rapeyko, Karen S. Arias, Maria J. Climent, Avelino Corma, Sara Iborra
Monomers from biomass have been prepared from HMF and methylene active compounds through a one pot process using MIL-100(Fe)/TEMPO/NaNO2 as the catalytic system.

Polymers from biomass: one pot two-step synthesis of furilydenepropanenitrile derivatives with MIL-100(Fe) catalyst

Anastasia Rapeyko,a  Karen S. Arias,a  Maria J. Climent,a  Avelino Corma*a  and  Sara Iborra*a 

 Author affiliations

*Corresponding authors

aInstituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avenida de los Naranjos s/n, 46022 Valencia, Spain
E-mail: acorma@itq.upv.es, siborra@itq.upv.es
Fax: (+34) 963877809

Anastasia Rapeyko

Química

Instituto de Tecnologia Quimica UPV-CSIC

 Universitat Politècnica de València (UPV)

Valencia Area, Spain

Abstract

Furilydenepropanenitrile derivatives, which are useful as monomers, have been obtained in high yields by coupling the oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) and the Knoevenagel condensation of DFF with methylene active compounds in a one pot process.

The oxidation step was studied using an Fe containing metal–organic framework (MIL-100(Fe), and Fe(BTC)), a Cu containing MOF (Cu3(BTC)2), an Fe exchanged HY zeolite and homogeneous Fe salts in the presence of 2,2,6,6-tetramethylpiperidine-1-oxide (TEMPO) as a cocatalyst, NaNO2 as an additive and oxygen as the terminal oxidant.

The results showed that the synthesized MIL-100(Fe) post treated with NH4F was the most active catalyst achieving 100% HMF conversion with 100% selectivity to DFF and can be reused with good success.

Additionally, the catalytic system has been applied to the oxidation of different primary and secondary alcohols to aldehydes and ketones under mild reaction conditions with good success.

The second step, the Knoevenagel condensation of the obtained DFF with malononitrile or ethyl cyanoacetate, was performed taking advantage of the basicity of the reaction medium.

 

 

Diethyl 3,3´-(2,5-furandiyl)(2E,2’E)-bis(2-cyanoacrylate) (2b)

 

1H NMR (300 MHz, CDCl3): δ 8.07 (=CH, s, 2H), 7.62 (s, 2H, ArH), 4.38 (CH2, q, 4H, J = 7.1 Hz), 1.39 (CH3, t, 6H, J=7.1 Hz);

 

13C NMR (75 MHz, CDCl3): δ 161.4 (C=O), 151.7 (C), 138.0 (=CH), 121.9 (CN), 114.5 (CH), 103.6 (C-CN), 63.1 (O-CH2), 14.1 ppm (CH3).

 

MS m/z (%) 314 (M+ , 100), 286 (17), 269 (55), 240 (58), 214 (26), 196 (14), 170 (14), 142 (17), 114 (16), 89 (12), 29 (22).

 

 

 

2,2´-(2,5-Furandiyldimethylidyne)-bis-propanedinitrile (2a)

 

1H NMR (300 MHz, DMSO-d6): δ 8.45 (=CH, s, 2H), 7.66 (s, 2H, ArH).

 

13C NMR (75 MHz, DMSO-d6): δ 151.6 (CH), 143.7 (C), 124.9 (CH), 113.7, 112.3, 81.4 ppm (C).

 

MS m/z (%) 220 (M+ , 100), 193 (9), 157 (6), 105 (15), 77 (12).

 

 

 

2,5-diformylfuran:

1 H NMR (300 MHz, CDCl3): δ 9.85 (s, 2H, CHO), 7.33 (s, 2H, ArH).

 

13C NMR (75 MHz, CDCl3): δ 179.1 (CHO), 154.2 (C), 119.1 ppm (CH).

 

MS m/z (%) 124 (M+ , 100), 123 (70), 97 (100), 95 (24), 67 (5), 39 (27), 38 (14).

 

 

 

 

Instituto de Tecnología Química, Universitat Politècnica de València-Consejo Superior de Investigaciones Científicas, Avenida de los Naranjos s/n, 46022 Valencia, Spain

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Atom- and step-economical nucleophilic arylation of azaaromatics via electrochemical oxidative cross C-C coupling reactions

 

Atom- and step-economical nucleophilic arylation of azaaromatics via electrochemical oxidative cross C-C coupling reactions

Green Chem., 2017, 19,2931-2935
DOI: 10.1039/C7GC00789B, Communication

O. N. Chupakhin, A. V. Shchepochkin, V. N. Charushin
A simple and efficient electrochemical method for the synthesis of asymmetrical bi(het)aryls through direct functionalization of the C(sp2)-H bond in azaaromatics with fragments of (hetero)aromatic nucleophiles has been developed.

From the journal:

Green Chemistry

Atom- and step-economical nucleophilic arylation of azaaromatics via electrochemical oxidative cross C–C coupling reactions

O. N. Chupakhin,*ab  A. V. Shchepochkinab  and  V. N. Charushinab 

*Corresponding authors

aInstitute of Organic Synthesis of the Russian Academy of Sciences, 22 S. Kovalevskoy Street, 620990 Ekaterinburg, Russia
E-mail: chupakhin@ios.uran.ru

bUral Federal University, 19 Mira Street, 620002 Ekaterinburg, Russia

Abstract

The synthesis of asymmetrical bi(het)aryls through direct functionalization of the C(sp2)–H bond in azaaromatics with fragments of (hetero)aromatic nucleophiles has first been carried out under electrochemical oxidative conditions. This versatile method for C–C bond formation between two aryl fragments can be realized under very mild potential-controlled oxidative conditions, and it does require neither incorporation of any halogen atoms or other leaving groups, nor the use of metal catalysts. The use of the electrochemical SHN methodology for modification of azaaromatic compounds has first been demonstrated.

   

9-(1H-Indol-3-yl)-10-methylacridinium tetrafluoroborate (3e) Red crystals, 189 mg (96%). M.p.: 192-193 °C. 1H NMR (500 MHz, [D6]DMSO): δ 12.44 (s, 1H), 8.80 (d, 2H, J=9.5 Hz), 8.43-8.39 (m, 4H), 8.14 (d, 1H, J=2.6 Hz), 7.90-7.86 (m, 2H), 7.70 (d, 1H, J=8.2 Hz), 7.32 (t, 1H, J=7.4 Hz), 7.17-7.10 (m, 2H), 4.88 (s, 3H) ppm. 13C NMR (126 MHz, [D6]DMSO): δ 156.2, 141.2, 137.9, 136.5, 131.1, 130.5, 127.9, 127.1, 125.6, 122.9, 121.2, 119.0, 118.9, 112.7, 107.9, 38.6 ppm. Elem. Anal. Calcd. For C22H17N2BF4: C 66.69, H 4.33, N 7.07 Found: C 66.78, H 4.39, N 7.10.

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Catalytic carbonyl hydrosilylations via a titanocene borohydride-PMHS reagent system

Catalytic carbonyl hydrosilylations via a titanocene borohydride-PMHS reagent system

Catal. Sci. Technol., 2017, Advance Article

DOI: 10.1039/C7CY01088E, Paper

Godfred D. Fianu, Kyle C. Schipper, Robert A. Flowers II
Catalytic amounts of titanocene(III) borohydride, generated under mild conditions from commercially available titanocene dichloride, in concert with a stoichiometric hydride source is shown to effectively reduce aldehydes and ketones to their respective alcohols in aprotic media.

From the journal:

• Catalysis Science & Technology

Catalytic carbonyl hydrosilylations viaa titanocene borohydride–PMHS reagent system

Godfred D. Fianu,a  Kyle C. Schippera  and  Robert A. Flowers II*a 

 Author affiliations

*Corresponding authors

aDepartment of Chemistry, Lehigh University, Bethlehem, USA
E-mail: rof2@lehigh.edu

Abstract

Reduction of a wide range of aldehydes and ketones with catalytic amounts of titanocene borohydride in concert with a stoichiometric poly(methylhydrosiloxane) (PMHS) reductant is reported. Preliminary mechanistic studies demonstrate that the reaction is mediated by a reactive titanocene(III) complex, whose oxidation state remains constant throughout the reaction.

Godfred Fianu

Lehigh University , Bethlehem · Department of Chemistry

Robert A Flowers

Danser Distinguished Faculty Chair in Chemistry and Deputy Provost for Faculty Affairs

Lehigh University , Bethlehem · Department of Chemistry

Lehigh University

Department of Chemistry

Bethlehem, United States

Phenyl methanol (2-c)
Phenyl methanol (2-c) was prepared from benzaldehyde (1-c) by the procedure outlined
in GP1. NMR analysis showed 100% conversion in 1 hour. 86% isolated yield of alcohol
product was obtained after complete workup.

1H NMR (400 MHz, CDCl3) δ 7.37 – 7.26 (m,5H), 4.59 (s, 2H), 2.99 (s, 1H).

13C NMR (101 MHz, CDCl3) δ 140.92, 128.56, 127.60, 127.07,77.52, 77.20, 76.88, 65.04.

 

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NaBH4, twin screw technology (i.e., granulator, melt extruder, etc.) to yield the desired product in a continuous manner

In this work the application of green chemistry principles such as process intensification and the replacement of reagents and solvents to more benign alternatives were coupled with the advantages of continuous manufacturing. The reduction of lipophilic aromatic aldehydes using an aqueous alkaline solution of NaBH4 was achieved by means of mechanical shearing and kneading provided by a custom-made batch reactor at the lab scale and a twin screw extruder at the kilo scale. The process was run continuously for 17 min to yield 1.41 kg of product (89% purity). The benefits of running the process in a continuous manner instead a conventional fed-batch mode were discussed in terms of both environmental and economic factors.

Screwing NaBH4 through a Barrel without a Bang: A Kneaded Alternative to Fed-Batch Carbonyl Reductions

Valerio Isoni* , Ken Mendoza, Eleen Lim, and Soo Khean Teoh

Institute of Chemical and Engineering Sciences, 1 Pesek Road, 627833, Jurong Island, Singapore

Org. Process Res. Dev., Article ASAP

DOI: 10.1021/acs.oprd.7b00107

 

http://pubs.acs.org/doi/suppl/10.1021/acs.oprd.7b00107

*E-mail: isoniva@ices.a-star.edu.sg.

 

 

Institute of Chemical and Engineering Sciences, 1 Pesek Road, 627833, Jurong Island, Singapore

The chemical industry has been a major part of the Singapore economy for many years, based on a strong foundation as a major oil refining centre with a long history, and strategically placed at the heart of the Asia - Pacific region. In recent years the pharmaceuticals industry has also seen major growth, so that chemistry and chemical engineering science now make a very significant contribution to Singapore's economy.

In order to strengthen this position and to foster future development to grow from dependence solely on manufacturing to secure a more knowledge dependant, high tech research and development based business environment, Agency for Science, Technology and Research (A*STAR) and Economic Development Board (EDB) looked at how to bolster the local science and technology base. As a result, the Institute of Chemical and Engineering Sciences (ICES) came into being, to provide highly trained R&D manpower, to establish a strong science base and to develop technology and infrastructure to support future growth.

Starting from a small centre in the National University of Singapore (NUS), ICES was established as an autonomous national research institute under A*STAR on October 1st 2002. Since that time, we have grown rapidly. We have established world leading laboratories, pilot facilities, and the necessary infrastructure to carry out a world class research programme in chemistry and chemical engineering sciences. We have the capability to cover the range of activities from exploratory research to process development, optimisation and problem solving. We can go from very small lab scale right to kg and pilot scale in one organisation, with all of the necessary skills directly at hand and integrated into a project oriented environment.

 

 

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