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Alexander Dömling - One of the best experts on this subject based on the ideXlab platform.
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Isocyanide 2.0
Green Chemistry, 2020Co-Authors: Pravin Patil, Maryam Ahmadianmoghaddam, Alexander DömlingAbstract:The Isocyanide functionality due to its dichotomy between carbenoid and triple bond characters, with a nucleophilic and electrophilic terminal carbon, exhibits unusual reactivity in organic chemistry exemplified for example in the Ugi reaction. Unfortunately, the over proportional use of only a few Isocyanides hampers novel discoveries about the fascinating reactivity of this functional group. The synthesis of a broad range of Isocyanides with multiple functional groups is lengthy, inefficient, and exposes the chemist to hazardous fumes. Here we present an innovative Isocyanide synthesis overcoming these problems by avoiding the aqueous workup which we exemplify by parallel synthesis from a 0.2 mmol scale performed in 96-well microtiter plates up to a 0.5 mol multigram scale. The advantages of our methodology include an increased synthesis speed, very mild conditions giving access to hitherto unknown or highly reactive classes of Isocyanides, rapid access to large numbers of functionalized Isocyanides, increased yields, high purity, proven scalability over 5 orders of magnitude, increased safety and less reaction waste resulting in a highly reduced environmental footprint. For example, the hitherto believed to be unstable 2-isocyanopyrimidine, 2-acylphenylIsocyanides and even o-isocyanobenzaldehyde could be accessed on a preparative scale and their chemistry was explored. Our new Isocyanide synthesis will enable easy access to uncharted Isocyanide space and will result in many discoveries about the unusual reactivity of this functional group.
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an efficient passerini tetrazole reaction pt 3cr
Green Chemistry, 2016Co-Authors: Ajay L Chandgude, Alexander DömlingAbstract:A sonication accelerated, catalyst free, simple, high yielding and efficient method for the Passerini-type three component reaction (PT-3CR) has been developed. It comprises reaction of an aldehyde/ketone, a Isocyanide and a TMS-azide in methanol:water (1:1) as the solvent system. Use of sonication not only accelerated the rate of the reaction but also provided up to quantitative yields. This reaction is applicable to a broad scope of aldehyde/ketone and Isocyanides.
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Leuckart-Wallach Approach to Sugar Isocyanides and Its IMCRs
Synthesis, 2015Co-Authors: Dinos Neochoritis, Ji Zhang, Alexander DömlingAbstract:We utilize our recently introduced Leuckart–Wallach approach to synthesize anomeric sugar Isocyanides in good overall yields and two steps. Moreover, we show the general usage of these Isocyanides in Isocyanide-based multicomponent reactions (IMCRs) to produce eight different compounds/scaffolds.
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Efficient Isocyanide-less Isocyanide-based multicomponent reactions.
Organic letters, 2015Co-Authors: Constantinos G. Neochoritis, Silvia Stotani, Bhupendra Mishra, Alexander DömlingAbstract:Isocyanides are the “Jekyll and Hyde” of organic chemistry allowing for extremely interesting transformations that are not only extremely odorous but also noxious. Therefore, an Isocyanide-less Isocyanide-based multicomponent reaction (IMCR) has been developed, and this protocol is expected to replace many of the old procedures in the future not only in IMCR but in other areas of organic chemistry as well.
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The Chemistry of Isocyanides, their MultiComponent Reactions and their Libraries
Molecules, 2003Co-Authors: Ivar Ugi, B. Werner, Alexander DömlingAbstract:Abstract : The first century of Isocyanide chemistry, which was then still a rather empty part of Organic Chemistry, began in 1859. In 1958 Isocyanides became generally available by dehydration the formylamines. One year later the four component reaction of Isocyanides (U-4CR) was introduced. This one-pot reaction is accomplished just by mixing amines, carbonyl compounds,suitable acids and Isocyanides. Most chemical reactions have their own ”scope and limitation”, whereas the -4CR can convert almost all combinations Uof educts into their products. Until 1995 this chemistry was moderately used, but since then a new era of he U-4CR and its unions with further reactions have become increasinglyt popular, particularly as libraries. In industry this chemistry became one of its most often used methods of finding new desirable products. In contrast to most other areas of chemistry, Isocyanide chemistry is not yet exhausted and still much progress can be expected there. Key words : Isocyanides, four component reaction, Ugi-reaction (U-4CR), multicomponent reaction (MCR), libraries.
Laurence Grimaud - One of the best experts on this subject based on the ideXlab platform.
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Three‐Component Metal‐Free Arylation of Isocyanides
Angewandte Chemie (International ed. in English), 2013Co-Authors: Unnamatla M. V. Basavanag, Laurent El Kaim, Aurélie Dos Santos, Rocío Gámez-montaño, Laurence GrimaudAbstract:Though the efficiency of Isocyanides as strong ligands for transition metals was recognized very early, the disclosure of metal-catalyzed arylation of Isocyanides has only been explored quite recently. In most of these studies, the formation of a metal/aryl complex starting from aryl iodide or bromide is followed by Isocyanide insertion and trapping of the metal/imidoyl complex with various nucleophiles (Scheme 1). These three-component couplings are mostly
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three component strategy toward 5 membered heterocycles from Isocyanide dibromides
Organic Letters, 2011Co-Authors: Laurent El Kaim, Laurence Grimaud, Pravin PatilAbstract:A three-component strategy starting from Isocyanides allows a straightforward synthesis of five-membered ring heterocycles. New cascades were developed involving the addition of a nitrogenated nucleophile—an azide or a tetrazole—on Isocyanide dibromides, an electrocyclization, and a Suzuki coupling, which afford new accesses to tetrazole and triazole scaffolds.
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Isocyanide-Based MulticomponentReaction ‘without’ Isocyanides
Synlett, 2009Co-Authors: Laurent El Kaim, Laurence Grimaud, Aurelie SchiltzAbstract:We present here a one-pot, four-component sequence that affords Ugi-type adducts starting from simple benzyl or allyl bromides. The Isocyanides are prepared in situ under alkylation of silver cyanide salts and the resulting mixture is directly used in a Ugi―Smiles coupling.
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Isocyanide-based two-step three-component keteneimine formation.
Organic letters, 2009Co-Authors: Didier Coffinier, Laurent El Kaim, Laurence GrimaudAbstract:The addition of Isocyanides to acyl chlorides (Isocyanide-Nef reaction) leads to imidoyl chlorides which can later be treated with trialkylphosphites to afford new keteneimines in a Perkow-type reaction. The whole sequence may be performed without any solvent, and the resulting keteneimine may easily be converted to phosphorylated tetrazoles and triazoles.
Armin De Meijere - One of the best experts on this subject based on the ideXlab platform.
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ortho lithiophenyl Isocyanide a versatile precursor for 3h quinazolin 4 ones and 3h quinazolin 4 thiones
Organic Letters, 2009Co-Authors: Alexander V Lygin, Armin De MeijereAbstract:ortho-Lithiophenyl Isocyanide has been generated from ortho-bromophenyl Isocyanide and successfully employed toward the synthesis of 2-substituted phenyl Isocyanides as well as 2,3-disubstituted 3H-quinazoline-4-ones and 3H-quinazolin-4-thiones.
Robert J. Angelici - One of the best experts on this subject based on the ideXlab platform.
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Bulk Gold-Catalyzed Reactions of Isocyanides, Amines, and Amine N-Oxides
Organometallics, 2012Co-Authors: Erik R. Klobukowski, Robert J. AngeliciAbstract:Bulk gold powder (∼5–50 μm particles) catalyzes the reactions of Isocyanides with amines and amine N-oxides to produce ureas. The reaction of n-butyl Isocyanide (nBu–N≡C) with di-n-propylamine and N-methylmorpholine N-oxide in acetonitrile, which was studied in the greatest detail, produced 3-butyl-1,1-dipropylurea (O═C(NHnBu)(NnPr2)) in 99% yield at 60 °C within 2 h. Sterically and electronically different Isocyanides, amines, and amine N-oxides react successfully under these conditions. Detailed studies support a two-step mechanism that involves a gold-catalyzed reaction of adsorbed Isocyanide with the amine N-oxide to form an isocyanate (RN═C═O), which rapidly reacts with the amine to give the urea product. These investigations show that bulk gold, despite its reputation for poor catalytic activity, is capable of catalyzing these reactions.
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Gold metal-catalyzed reactions of Isocyanides with primary amines and oxygen: analogies with reactions of Isocyanides in transition metal complexes.
Journal of the American Chemical Society, 2006Co-Authors: Mihaela D. Lazar, Robert J. AngeliciAbstract:Despite its generally poor catalytic properties, bulk gold metal is observed to catalyze reactions of Isocyanides (C⋮N−R) with primary amines (H2N−R‘) and O2 to give carbodiimides (R−NCN−R‘) at room temperature and above. Detailed infrared reflection absorption spectroscopic (IRRAS) and kinetic studies show that the reaction occurs by initial η1-adsorption of the Isocyanide on the Au surface, which activates the Isocyanide to attack by the amine. This attack is the rate-determining step in the catalytic cycle and has characteristics very similar to those of amine reactions with coordinated Isocyanides in transition metal complexes. However, the metallic Au surface provides a pathway involving O2 to give the carbodiimide product whereas homogeneous metal ion catalysts give formamidines [HC(NR)(NHR‘)].
Ahmad Shaabani - One of the best experts on this subject based on the ideXlab platform.
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Isocyanide-based consecutive Bargellini/Ugi reactions: an efficient method for the synthesis of pseudo-peptides containing three amide bonds
Amino Acids, 2020Co-Authors: Hassan Farhid, Ahmad Shaabani, Mohammad Taghi Nazeri, Mahsa Armaghan, Christoph JaniakAbstract:Isocyanide-based consecutive Bargellini/Ugi multicomponent reactions as a combinatorial strategy have been developed for the synthesis of new class of pseudo-peptides. Via Bargellini reaction 3-carboxamido-isobutyric acids are prepared using acetone, chloroform, sodium hydroxide, and Isocyanides. Then, using Ugi multicomponent reaction strategy, pseudo-peptides containing three amide bonds are synthesized using the Bargellini reaction product, aldehydes, amines, and Isocyanides. This is an efficient and eco-friendly approach for easy access to wide variety of structurally diverse, drug-like pseudo-peptides from cheap and readily available precursors in high yields.
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The status of Isocyanide-based multi-component reactions in Iran (2010–2018)
Molecular Diversity, 2020Co-Authors: Ahmad Shaabani, Reza Mohammadian, Ronak Afshari, Seyyed Emad Hooshmand, Mohammad Taghi Nazeri, Siamak JavanbakhtAbstract:Isocyanides as key intermediates and magic reactants have been widely applied in organic reactions for direct access to a broad spectrum of remarkable organic compounds. Although the history of these magical compounds dates back more than 100 years, it still has been drawing widespread attention of chemists who confirmed their versatility and effectiveness. Because of their wide spectrum of pharmacological, industrial and synthetic applications, many reactions with the utilization of Isocyanides are reported in the literature. In this context, Iranian scientist played a significant role in the growth of Isocyanides chemistry. The present review article covers literature from the period starting from 2010 onward and encompasses new synthetic routes and organic transformation involving Isocyanides by Iranian researchers. During this period, a diverse range of Isocyanide-based multi-component reactions (I-MCRs) has been reported such as a new modification of Ugi, post-Ugi, Passerini and Groebke–Blackburn–Bienayme condensation reactions, Isocyanide-based [1 + 4] cycloaddition reactions, Isocyanide-acetylene-based MCRs, Isocyanide and Meldrum’s acid-based MCRs, several unexpected reactions besides green mediums and novel catalytic systems for the synthesis of diverse kinds of pharmaceutically and industrially remarkable heterocyclic and linear organic compounds. This review also emphasizes the neoteric applications of I-MCR for the synthesis of valuable peptide and pseudopeptide scaffolds, enzyme immobilization and functionalization of materials with tailorable properties that can play important roles in the plethora of applications. Graphic abstract
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tandem oxidative Isocyanide based cycloaddition reactions in the presence of mil 101 cr as a reusable solid catalyst
Tetrahedron, 2018Co-Authors: Ahmad Shaabani, Heshmatollah Sepahvand, Mostafa M Amini, Alireza Hashemzadeh, Mahmoud Borjian Boroujeni, Elham BadaliAbstract:Abstract The tandem oxidative three-component synthesis of two types of the heterocycles such as furans and imidazopyridines, via Isocyanides [1+4] cycloaddition reactions in the presence of MIL-101(Cr) under aerobic conditions are reported. When the 4-toluenesulfonylmethyl Isocyanide was used, an unexpected [3+2] cycloaddition reaction of Isocyanides with aldehydes accomplished and dihydrophenyloxazoles and phenyloxazoles produced. These syntheses were successfully carried out using a wide scope of the substrates.
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a re engineering approach synthesis of pyrazolo 1 2 a pyrazoles and pyrano 2 3 c pyrazoles via an Isocyanide based four component reaction under solvent free conditions
Tetrahedron Letters, 2016Co-Authors: Ahmad Shaabani, Heshmatollah Sepahvand, Mina Keramati NejadAbstract:Abstract A new protocol based on a re-engineering approach has been developed for the efficient synthesis of pyrazolo[1,2- a ]pyrazoles and pyrano[2,3- c ]pyrazoles via an Isocyanide-based four-component reaction of dialkyl acetylenedicarboxylates, Isocyanides, and ethyl acetoacetate with hydrazine hydrate or phenylhydrazine. The reactions were carried out under solvent- and catalyst-free conditions at mild temperatures and short times in good yields.
