- New observations on peptide bond formation using CDMT
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The optimized formation of the peptide bond by means of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) has been found to occur rapidly and essentially quantitatively in a one-pot, one-step procedure. This new method is effective for the coupling of a variety of reactive partners, including chiral amino acids (e.g. N-acetyl-L-leucine) without significant loss of configuration. Significant racemization was observed when the typical literature conditions were used, due to the formation of an azlactone intermediate which is configurationally unstable under the reaction conditions. A simpler, precipitative workup procedure is also disclosed in this report.
- Garrett, Christine E.,Jiang, Xinglong,Prasad, Kapa,Repi?, Oljan
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- Mechanistic studies of DCC/HOBt-mediated reaction of 3-phenylpropionic acid with benzyl alcohol and studies on the reactivities of 'active ester' and the related derivatives with nucleophiles
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Despite of the extensive study for peptide synthesis, DCC-mediated esterification is left still unclear. Therefore, DCC- and DCC/HOBt-mediated reactions of 3-phenylpropionic acid (1) with benzyl alcohol were carried out under several mechanistic considerations. Further, in order to determine the reactivities of the so-called 'active esters' compounds changing the substituents bearing carbonyl and related derivatives group for the purpose of the development of new class of non-symmetry cross-linkers, we have studied the reaction of model compounds, N-(3-phenylpropionyloxy)benzotriazole (6), N-(3-phenylpropionyloxy)phthalimide (7), 3-phenylpropionyloxybenzothiazole (8), and N-(3-phenylpropionyl)benzotriazole (9) with various nucleophiles under similar conditions were carried out for the comparison. It was revealed to exhibit the order of 6>>8>9>7.
- Sheikh, Md. Chanmiya,Takagi, Shunsuke,Yoshimura, Toshiaki,Morita, Hiroyuki
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- Development of chlorotriazine polymer dehydrocondensing reagents (Poly-Trzs)
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Polymer-type dehydrocondensing reagents comprising of a triazine dehydrocondensing reagent, itself in a polymerized form (Poly-Trz-MMs'), have been developed by exploiting the chemical properties of cyanuric chloride that readily binds to alcohol or amines. A chlorotriazine polymer bearing two alkoxy substituents at the 4- and 6- positions (Poly-O-Trz-Cl) was prepared by alternating copolymerization between cyanuric chloride and tetra(ethylene glycol). Similarly, polymers bearing both alkoxy and amino substituents (Poly-N-Trz-Cl) were synthesized from tetra(ethylene glycol) bis(4,6-dichlorotriazin-2-yl) ether 6 and tris(2-aminoethyl)amine 7 and/or ethylenediamine 8. All the polymers were shown to be good reagents for dehydrocondensation of carboxylic acids and amines in the presence of NMM, compared to the corresponding monomeric dehydrocondensing reagent (DMT-MM). The advantages of the polymeric reagents are as follows: (1) both the reaction and isolation procedure of dehydrocondensation can be greatly simplified, (2) the dehydrocondensation can be conducted in protic solvents as well as in common organic solvents, (3) the reagents can be efficiently prepared at a low cost, and (4) these reagents are considered eco-friendly, generating a lower amount of waste compared to conventionally related reagents because of high loading of the dehydrocondensing activity (ca. 3 mequiv/g).
- Kunishima, Munetaka,Yamamoto, Kazuyoshi,Hioki, Kazuhito,Kondo, Tomohito,Hasegawa, Masumi,Tani, Shohei
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- Tert-butoxide-assisted amidation of esters under green conditions
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Efficient and green amidation reactions are of great importance. In this work, we demonstrate the tert-butoxide-assisted amidation of esters with amines under ambient conditions. Aliphatic and/or aromatic esters were converted into the corresponding amides under mild conditions in good to excellent yields. It is noteworthy that the reaction is highly efficient, rapid, versatile, green and economical, and will find great practical application in organic synthesis, biochemistry, and industrial chemistry. Georg Thieme Verlag Stuttgart. New York.
- Kim, Bo Ram,Lee, Hyung-Geun,Kang, Seung-Beom,Sung, Gi Hyeon,Kim, Jeum-Jong,Park, Jong Keun,Lee, Sang-Gyeong,Yoon, Yong-Jin
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Read Online
- Development of novel polymer-type dehydrocondensing reagents comprised of chlorotriazines
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A novel immobilized dehydrocondensing reagent comprised of a triazine-type dehydrocondensing reagent itself in a polymerized form was synthesized by copolymerization between tetra(ethylene glycol) bis(dichlorotriazinyl) ether and tris(2-aminoethyl)amine.
- Kunishima, Munetaka,Yamamoto, Kazuyoshi,Watanabe, Yasunobu,Hioki, Kazuhito,Tani, Shohei
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Read Online
- Mild Amide-Cleavage Reaction Mediated by Electrophilic Benzylation
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An extremely mild method for amide-cleavage by using the triazine-based benzylating reagent 4-(4,6-diphenoxy-1,3,5-triazin-2-yl)-4-benzylmorpholinium trifluoromethanesulfonate (DPT-BM), which spontaneously releases benzyl cation species when being dissolved at room temperature, has been developed. O-Benzylation of the amide with DPT-BM and the subsequent hydrolysis of the resulting intermediate benzyl imidate salt afford the corresponding amine and benzyl ester, which can be converted by hydrogenolysis into a carboxylic acid under neutral conditions. O-Benzylation proceeds depending on both steric and electronic factors around the amide group. Thus, some amides have been selectively cleaved over other amides. Furthermore, intramolecular chemoselective cleavage of an amide group in the presence of an ester group was achieved. Such selective hydrolytic reactions cannot be performed with Meerwein reagents as well as under acidic or basic hydrolytic conditions.
- Yamada, Kohei,Karuo, Yukiko,Tsukada, Yuichi,Kunishima, Munetaka
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Read Online
- Visible Light-Driven Efficient Synthesis of Amides from Alcohols using Cu?N?TiO2 Heterogeneous Photocatalyst
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Amides were synthesized from alcohols and amines in high yields using an in situ generated active ester of N-hydroxyimide with our developed Cu?N?TiO2 catalyst at room temperature using oxygen as a sole oxidant under visible light. The catalyst can be easily prepared, robust, and recycled four times without a considerable change in catalytic activity. This developed protocol applies to a wide substrate scope and has good functional group tolerance. The application of this amidation reaction has been successfully demonstrated for the synthesis of moclobemide, an antidepressant drug, and an analog of the itopride drug on a gram scale.
- Singha, Krishnadipti,Ghosh, Subhash Chandra,Panda, Asit Baran
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Read Online
- Immobilized triazine-type dehydrocondensing reagents for carboxamide formation: ROMP-Trz-Cl and ROMP(OH)-Trz-Cl
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New triazine-type dehydrocondensing reagents, such as ROMP-Trz-Cl and ROMP(OH)-Trz-Cl, were synthesized by a ring opening metathesis polymerization (ROMP) method, and these showed higher loading than conventional polymer-supported condensing reagents. The
- Hioki, Kazuhito,Kameyama, Satomi,Tani, Shohei,Kunishima, Munetaka
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Read Online
- Study of 1,3,5-triazine-based catalytic amide-forming reactions: Effect of solvents and basicity of reactants
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Effect of the basic property of reactants (tertiary amine catalysts, a substrate amine, and acid neutralizers) on catalytic dehydrocondensation between a carboxylic acid and an amine by using 2-chloro-4,6- dimethoxy-1,3,5-triazine (CDMT) was studied. The
- Kunishima, Munetaka,Kitamura, Masanori,Tanaka, Hiroyuki,Nakakura, Ichiro,Moriya, Takahiro,Hiokib, Kazuhito
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Read Online
- Approach to green chemistry of DMT-MM: Recovery and recycle of coproduct to chloromethane-free DMT-MM
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A simple procedure for the isolation of 2-hydroxy-4,6-dimethoxy-1,3,5-triazine (HO-DMT), a coproduct arising from dehydrating condensation using 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) has been established. HO-DMT can be recycled by treatment with POCl3 to give 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT), which is further converted to DMT-MM. Alternatively, reaction with triflic anhydride followed by addition of N-methylmorpholine gives DMT-MM triflate.
- Kunishima, Munetaka,Hioki, Kazuhito,Wada, Ayako,Kobayashi, Hiroko,Tani, Shohei
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Read Online
- Imido-substituted triazines as dehydrative condensing reagents for the chemoselective formation of amides in the presence of free hydroxy groups
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In this paper, we discuss the synthesis of imido-substituted chlorotriazines and demonstrate their use in dehydrative condensation reactions. Chemoselective amide-forming reactions of amino alcohols using succinimido-substituted chlorotriazine (2A) proceeded smoothly. Occasionally, nonselectivity was problematic during the synthesis of hydroxy-substituted amides. Moreover, it was noteworthy that this method was applicable to hydroxy-substituted carboxylic acids that could have formed a lactone or an ester during the carboxylic acid activation step. The imido-substituted chlorotriazine (2A) was superior to the amido-substituted chlorotriazine and 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) in terms of reaction rates and yields.
- Kitamura, Masanori,Sasaki, Suguru,Nishikawa, Riho,Yamada, Kohei,Kunishima, Munetaka
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Read Online
- Development of a triazinedione-based dehydrative condensing reagent containing 4-(dimethylamino)pyridine as an acyl transfer catalyst
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A new triazinedione-based reagent, (N,N′-dialkyl)triazinedione-4-(dimethylamino)pyridine (ATD-DMAP) was developed for the operationally simple dehydrative condensation of carboxylic acids. This reagent comprises an ATD core and DMAP as the leaving group, which is liberated into the reaction system to accelerate acyl transfer reactions. Upon adding ATD-DMAP to a mixture of carboxylic acids and alcohols in the presence of an amine base, the corresponding esters were formed rapidly at room temperature. Moreover, dehydrative condensation between carboxylic acids and amines using ATD-DMAP proceeded in high yield.
- Liu, Jie,Fujita, Hikaru,Kitamura, Masanori,Shimada, Daichi,Kunishima, Munetaka
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supporting information
p. 4712 - 4719
(2021/06/11)
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- Chemoselective Amide-Forming Ligation Between Acylsilanes and Hydroxylamines Under Aqueous Conditions
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We report the facile amide-forming ligation of acylsilanes with hydroxylamines (ASHA ligation) under aqueous conditions. The ligation is fast, chemoselective, mild, high-yielding and displays excellent functional-group tolerance. Late-stage modifications of an array of marketed drugs, peptides, natural products, and biologically active compounds showcase the robustness and functional-group tolerance of the reaction. The key to the success of the reaction could be the possible formation of the strong Si?O bond via a Brook-type rearrangement. Given its simplicity and efficiency, this ligation has the potential to unfold new applications in the areas of medicinal chemistry and chemical biology.
- Deng, Xingwang,Zhou, Guan,Tian, Jing,Srinivasan, Rajavel
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p. 7024 - 7029
(2020/12/29)
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- Efficiency Enhancement of a Photocatalytic Decarbonylation of an Aminocyclopropenone by Benzothiophene Substitution
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To improve the efficiency of the photocatalytic decarbonylation of cyclopropenones, the effects of substituents on cyclopropenone were explored. A benzothiophene-substituted aminocyclopropenone exhibited significantly improved decarbonylation efficiency t
- Mishiro, Kenji,Nomura, Mitsuki,Furuyama, Taniyuki,Kunishima, Munetaka
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p. 3625 - 3636
(2021/03/03)
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- Enhancement of the carbamate activation rate enabled syntheses of tetracyclic benzolactams: 8-oxoberbines and their 5- And 7-membered C-ring homologues
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A route to the direct amidation of aromatic-ring-tetheredN-carbamoyl tetrahydroisoquinoline substrates was developed. This route enabled general access to 8-oxoberberines and their 5- and 7- membered C-ring homologues. It overcomes the undesired tandem side-reactions that result in the destruction of the isoquinoline backbone, which inevitably occurred under our previously reported superacidic carbamate activation method.
- Kurouchi, Hiroaki
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supporting information
p. 653 - 658
(2021/02/06)
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- N-acyltriazinedione; a novel acylating reagent synthesized from a triazinone-type condensing reagent
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In this paper, we report the synthesis of N-acyltriazinedione via the unexpected O–N acyl rearrangement of acyloxytriazinone and its utility as an acylating reagent. N-Acyltriazinedione can be isolated by silica gel column chromatography and reacts with amines in the absence of any base to give the corresponding amides in good yields.
- Yamada, Kohei,Lee, Jeongsu,Kota, Mika,Karuo, Yukiko,Kitamura, Masanori,Kunishima, Munetaka
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p. 498 - 502
(2021/05/27)
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- Trizaine-based dehydrative condensation reagents bearing carbon-substituents
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Herein, we report on the synthesis of alkyl-, aryl-, and alkynyl-substituted chlorotriazines and their ammonium salts, and demonstrate their utility in dehydrative condensation reactions. Although the electrophilicity of these reagents is mainly dependent on the hybridization of the carbon-substituents, it was found that bulky 2,6-dimethylphenyl group-substituted reagents resulted in the highest product yields because of a slight increase in reagent electrophilicity and/or steric hindrance favorable for desired dehydrative condensation reactions.
- Kitamura, Masanori,Komine, Sayaka,Kunishima, Munetaka,Yamada, Kohei
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- Diprotonative stabilization of ring-opened carbocationic intermediates: conversion of tetrahydroisoquinoline to triarylmethanes
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Superacid-promoted conversion of tetrahydroisoquinolines to triarylmethanes via tandem reactions of C-N bond scission, Friedel-Crafts alkylation, C-O bond scission, and electrophilic aromatic amidation was developed. Dication formation was important for stabilizing the ring-opened carbocationic intermediate, which is a new role for diprotonation in reaction mechanisms. This journal is
- Kurouchi, Hiroaki
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supporting information
p. 8313 - 8316
(2020/08/17)
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- Development of Triazinone-Based Condensing Reagents for Amide Formation
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Novel triazinone-based condensing reagents have been developed. The palladium-catalyzed O-N allylic rearrangement of 2-(allyloxy)-4,6-dichloro-1,3,5-triazine and subsequent regioselective substitution using alcohols and an amine afforded chlorotriazinones, which can be readily converted using N-methylmorpholine into the corresponding condensing reagents. The condensation of carboxylic acids and amines using these reagents proceeded to afford the desired amides in good yields. In comparison with 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride, the newly synthesized triazinone-based condensing reagents exhibited higher reactivity.
- Yamada, Kohei,Kota, Mika,Takahashi, Kensuke,Fujita, Hikaru,Kitamura, Masanori,Kunishima, Munetaka
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p. 15042 - 15051
(2019/11/19)
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- Phototriggered Active Alkyne Generation from Cyclopropenones with Visible Light-Responsive Photocatalysts
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A photocatalytic active alkyne generation reaction was developed using cyclopropenone as a starting reagent. Visible light-responsive photocatalysts induced cyclopropenone decarbonylation. The resulting highly reactive alkyne could be used directly, witho
- Mishiro, Kenji,Kimura, Takeshi,Furuyama, Taniyuki,Kunishima, Munetaka
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supporting information
p. 4101 - 4105
(2019/06/17)
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- Antagonism of quorum sensing phenotypes by analogs of the marine bacterial secondary metabolite 3-methyl-N-(20-phenylethyl)-butyramide
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Quorum sensing (QS) antagonists have been proposed as novel therapeutic agents to combat bacterial infections. We previously reported that the secondary metabolite 3-methyl-N-(20-phenylethyl)-butyramide, produced by a marine bacterium identifie
- Meschwitz, Susan M.,Teasdale, Margaret E.,Mozzer, Ann,Martin, Nicole,Liu, Jiayuan,Forschner-Dancause, Stephanie,Rowley, David C.
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- A Hydroperoxide-Mediated Decarboxylation of α-Ketoacids Enables the Chemoselective Acylation of Amines
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Strategies for the formation of amide bonds, that is, one of the most basic and important transformations in organic synthesis, have so far focused predominantly on dehydration reactions. Herein, we report and demonstrate the practical utility of a novel decarboxylative amidation of α-ketoacids by using inexpensive tert-butyl hydroperoxide (TBHP), which is characterized by high yields, a broad substrate scope, mild reaction conditions, and a unique chemoselectivity. These features enable the synthesis of peptides from amino acid derived α-ketoacids under preservation of the stereochemical information.
- Nanjo, Takeshi,Kato, Natsuki,Zhang, Xuan,Takemoto, Yoshiji
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supporting information
p. 15504 - 15507
(2019/11/14)
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- METHOD FOR SYNTHESISING AMIDES
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The present invention relates to a method for synthesising amides that is of general applicability. The method may be performed in vitro or in vivo. Cell lines for use in the in vivo methods also form aspects of the invention. The method for synthesising a non-natural amide comprises: a. reaction of a carboxylic acid with a naturally occurring CoA ligase or a variant thereof; and b. reaction of the product of step a with an amine in the presence of a naturally occurring acyltransferase or a variant thereof; with the proviso that where the CoA ligase and acyltransferase are both naturally occurring, they are not derived from the same source species and do not act sequentially in a metabolic pathway; and with the proviso that the non-natural product is not N-(E)-p-coumaroyl-3-hydroxyanthranilic acid or N-(E)-p-caffeoyl-3-hydroxyanthranilic acid. Further, a method for producing an active pharmaceutical ingredient by the aforementioned method and host cells for carrying out said methods are envisaged.
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Page/Page column 32-34
(2018/03/06)
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- Triazinone compound
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PROBLEM TO BE SOLVED: To provide a novel compound useful as a dehydration condensation agent. SOLUTION: The present invention provides a triazinone compound represented by formula (I) [where each symbol is as defined in the specifications], and a use of the compound as a dehydration condensation agent. SELECTED DRAWING: None COPYRIGHT: (C)2017,JPOandINPIT
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Paragraph 0277; 0278; 0279; 0282; 0284
(2017/10/11)
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- Phototriggered Dehydration Condensation Using an Aminocyclopropenone
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A phototriggered dehydration condensation using an aminocyclopropenone has been developed. The UV irradiation of an aminocyclopropenone generated a highly reactive ynamine in situ and the dehydration condensation of a carboxylic acid and an amine coexisting in the reaction solution smoothly proceeded to afford an amide. This reaction is completely controllable by the ON/OFF states of a UV lamp.
- Mishiro, Kenji,Yushima, Yuki,Kunishima, Munetaka
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supporting information
p. 4912 - 4915
(2017/09/23)
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- Nickel/Photoredox-Catalyzed Amidation via Alkylsilicates and Isocyanates
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A nickel/photoredox, dual-catalyzed amidation reaction between alkylsilicate reagents and alkyl/aryl isocyanates is reported. In contrast to the previously reported reductive coupling process, this protocol is characterized by mild reaction conditions and the absence of a stoichiometric reductant. A mechanistic hypothesis involving a nickel-isocyanate adduct is proposed based on literature precedent and further validation by experimental results.
- Zheng, Shuai,Primer, David N.,Molander, Gary A.
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p. 7957 - 7961
(2017/11/10)
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- DEHYDRATION CONDENSATION AGENT
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PROBLEM TO BE SOLVED: To provide a novel compound useful as a condensation agent when producing a carboxylic acid derivative, such as ester and amide, by a dehydration condensation reaction, and a dehydration condensation agent comprising the compound. SOLUTION: The present invention provides a triazine quaternary ammonium compound represented by formula (I) and a dehydration condensation agent comprising the compound [R1 is C1-4 alkyl group; R2 and R3 independently represent a substituted/unsubstituted alkyl group, a substituted/unsubstituted secondary cyclic amino group formed with a nitrogen atom bonded thereto, or the like; X1 is a substituted/unsubstituted alkoxy group or a substituted/unsubstituted aryloxy group; X2 is a substituted/unsubstituted alkyl group, a substituted/unsubstituted cycloalkyl group, or the like; Y-is a counter anion with no nucleophilicity or with low nucleophilicity]. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
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Paragraph 0254-0256; 0261
(2018/09/02)
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- DEHYDRATION CONDENSATION AGENT
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PROBLEM TO BE SOLVED: To provide a novel compound useful as a dehydration condensation agent. SOLUTION: This invention relates to a compound represented by formula (I) [where each symbol is as defined in the specifications] and to a method for producing a carboxylic acid derivative (ester, amide or the like) that uses the compound as a dehydration condensation agent. SELECTED DRAWING: None COPYRIGHT: (C)2016,JPOandINPIT
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Paragraph 0346-0348; 0355; 0363
(2018/09/08)
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- Potent triazine-based dehydrocondensing reagents substituted by an amido group
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This study describes the synthesis of triazine-based dehydrocondensing reagents substituted by amido substituents and demonstrates their efficiency for dehydrocondensing reactions in MeOH and THF. N-Phenylbenzamido-substituted chlorotriazine is readily converted to a stable, non-hygroscopic triazinylammonium-based dehydrocondensing reagent that is superior to 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM) in terms of its reactivity in dehydrocondensing reactions.
- Kunishima, Munetaka,Kato, Daiki,Kimura, Nobu,Kitamura, Masanori,Yamada, Kohei,Hioki, Kazuhito
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supporting information
p. 1897 - 1903
(2016/10/05)
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- The Use of Ureates as Activators for Samarium Diiodide
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A novel mode of SmI2 activation has been developed using ureates as reaction promoters. Several ureates formed by treatment of the corresponding ureas with n-BuLi have been shown to activate SmI2 to a substantial extent toward the reduction of 1-chlorodecane. Complexes formed from SmI2 and various ureates have been shown to be useful for the reduction of a variety of organohalides, including substrates of low reactivity such as aryl fluorides. Because of ease of synthesis and low molecular weight, the conjugate base of triethylurea (TEU-) was of primary focus. Visible spectroscopy and reactivity data are consistent with the hypothesis that the same complex is being formed when SmI2 is combined with either 2 or 4 equiv of TEU-, in spite of the greater reactivity of SmI2/4 TEU- with some alkyl halides. We propose that the active reductant is an N,O chelate formed between SmI2 and 2 equiv of TEU-.
- McDonald, Chriss E.,Ramsey, Jeremy D.,McAtee, Christopher C.,Mauck, Joseph R.,Hale, Erin M.,Cumens, Justin A.
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p. 5903 - 5914
(2016/07/23)
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- TEMPO-Catalyzed Oxidative Amidation of Alcohols via Hexafluoroisopropyl Esters
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Stepwise oxidative amidation of alcohols using trichloroisocyanuric acid, a catalytic amount of TEMPO in combination with pyridine and hexafluoroisopropyl (HFIP) alcohol followed by amines is described. This procedure used HFIP esters as activating esters which were found to be very efficient acylating agents for amide bond formation. This process is compatible with a number of functional groups and acid-sensitive protecting groups.
- Vatèle, Jean-Michel
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p. 2280 - 2284
(2015/09/28)
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- Oxidative activation of dihydropyridine amides to reactive acyl donors
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Amides of 1,4-dihydropyridine (DHP) are activated by oxidation for acyl transfer to amines, alcohols and thiols. In the reduced form the DHP amide is stable towards reaction with amines at room temperature. However, upon oxidation with DDQ the acyl donor is activated via a proposed pyridinium intermediate. The activated intermediate reacts with various nucleophiles to give amides, esters, and thio-esters in moderate to high yields. This journal is
- Funder, Erik Daa,Trads, Julie B.,Gothelf, Kurt V.
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p. 185 - 198
(2015/01/16)
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- Polymer-anchored Ru(II) complex as an efficient catalyst for the synthesis of primary amides from nitriles and of secondary amides from alcohols and amines
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A polymer-anchored ruthenium(II) catalyst was synthesized and characterized. Its catalytic activity was evaluated for the preparation of primary amides from aqueous hydration of nitriles in neutral condition. A range of nitriles were successfully converted to their corresponding amides in good to excellent yields. The catalyst was also effective in the preparation of secondary amides from the coupling of alcohols and amines. The catalyst can be facilely recovered and reused six times without a significant decrease in its activity.
- Islam, Sk Manirul,Ghosh, Kajari,Roy, Anupam Singha,Molla, Rostam Ali
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p. 900 - 907
(2015/02/19)
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- Ruthenium-catalysed oxidation of alcohols to amides using a hydrogen acceptor
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A wider investigation into the synthesis of secondary amides from primary alcohols using a hydrogen acceptor using commercially available [Ru(p-cymene)Cl2]2 with bis(diphenylphosphino)butane (dppb) as the catalyst. The report looks at over 50 examples with varying functionality and steric bulk, whilst also covering the first reported results using microwave heating to effect the transformation.
- Watson, Andrew J.A.,Wakeham, Russell J.,Maxwell, Aoife C.,Williams, Jonathan M.J.
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supporting information
p. 3683 - 3690
(2014/05/20)
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- Role of linkers in tertiary amines that mediate or catalyze 1,3,5-triazine-based amide-forming reactions
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We studied 1,3,5-triazine-based amide-forming reactions that are mediated or catalyzed by various tert-amines. The representative tert-amine was trimethylamine, which has amido, 1,2,3-triazolyl, aryl, and alkyl linkers. It was found that electron-deficient aryl and heteroaryl linkers, particularly 1,2,3-triazolyl linkers, are superior. On the basis of our findings, we synthesized ligand catalysts, including a 1,2,3-triazolyl linker that connects a protein ligand to a trimethylamine moiety, and found that fluorescent-labeling of a targeting protein using the ligand catalysts proceeded in good yields.
- Kitamura, Masanori,Kawasaki, Fumitaka,Ogawa, Kouichi,Nakanishi, Shuichi,Tanaka, Hiroyuki,Yamada, Kohei,Kunishima, Munetaka
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p. 3709 - 3714
(2014/05/06)
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- Catalytic redox amidations of aldehydes with a polymer-supported peptide-N-heterocyclic carbene multifunctional catalyst
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We have prepared an oligomeric histidine-bound N-heterocyclic carbene precursor by coupling a carboxylic acid functionalized 1,2,4-triazolium salt to a peptide using solid-phase peptide synthesis. We have demonstrated that the resulting multifunctional resin-bound catalyst cooperatively facilitates redox amidation reactions of aldehydes and amines, a reaction not catalyzed by N-heterocyclic carbenes alone. Georg Thieme Verlag Stuttgart New York.
- Gondo, Chenaimwoyo A.,Bode, Jeffrey W.
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supporting information
p. 1205 - 1210
(2013/07/11)
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- Internal redox amidation of α,β-unsaturated aldehydes in ionic liquids. The electrochemical route
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A simple, N-heterocyclic carbene (NHC) activated synthesis of amides has been performed via electrolysis, carried out under galvanostatic control, of an ionic liquid (Bmim-BF4) followed by addition to the catholyte of an α,β-unsaturated aldehyde and amine. Amides have been isolated, in good to elevated yields, in the absence of any base, co-catalyst and organic solvent. The selectivity of amidation, versus the formation of imine as by-product, has been related to the molar ratio electrogenerated NHC/aldehyde. The results, obtained using ionic liquids and electrochemical procedures, have been compared with those obtained using organic solvents and classical procedures.
- Feroci, Marta,Chiarotto, Isabella,Inesi, Achille
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p. 692 - 699
(2013/04/10)
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- Metal-free oxidative amide formation with N-hydroxysuccinimide and hypervalent iodine reagents
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An oxidative amide formation using N-hydroxysuccinimide and hypervalent iodine reagents was developed. The method enables a wide range of aldehydes and amines to be coupled under mild reaction conditions providing amide in good to excellent yield. The radical species in the reaction mixture was observed for the first time using ESR measurement, and along with other mechanistic investigations, a plausible mechanism of the reaction was proposed.
- Yao, Haoyi,Tang, Yun,Yamamoto, Kana
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supporting information; experimental part
p. 5094 - 5098
(2012/10/08)
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- Amidation of aldehydes and alcohols through α-iminonitriles and a sequential oxidative three-component strecker reaction/thio-michael addition/alumina-promoted hydrolysis process to access β-mercaptoamides from aldehydes, amines, and thiols
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Mild and general alumina-promoted hydrolysis conditions for converting α-iminonitriles into carboxamides have been developed. In combination with the oxidative three-component Strecker reaction, the one-pot direct amidation of aldehydes and alcohols is reported. Subsequently, an Yb(OTf) 3-catalyzed Michael addition of thiols to α,β-unsaturated α-iminonitriles is reported for the synthesis of β-mercapto-α- iminonitriles. The successful integration of an oxidative Strecker reaction, thio-Michael addition, and neutral-alumina-promoted hydrolysis of β-mercapto-α-iminonitriles into a three-component one-pot process allowed us to develop the direct conversion of amines, aldehydes, and thiols into β-mercaptoamides. All of these procedures were applicable to aromatic and aliphatic amines and aldehydes. First direct: The direct amidation reactions of aldehydes and alcohols were performed in combination with the oxidative three-component synthesis of α-iminonitriles. In addition, β-mercaptoamides were readily accessed from α,β-unsaturated aldehydes, amines, and thiols by a sequential process that involved a three-component Strecker reaction, Yb(OTf)3-catalyzed thio-Michael addition, and hydrolysis of the resulting β-mercapto-α-iminonitriles (see scheme). Copyright
- Gualtierotti, Jean-Baptiste,Schumacher, Xavier,Fontaine, Patrice,Masson, Géraldine,Wang, Qian,Zhu, Jieping
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p. 14812 - 14819
(2013/01/15)
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- Aerobic amide bond formation with N-hydroxysuccinimide
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Breathe easy: Molecular oxygen is one of the most abundant, atom-efficient, and economical oxidants. An aerobic oxidative amide formation from aldehydes and amines is reported. The method uses a catalytic amount of Co(OAc) 2 and N-hydroxysuccinimide as reaction promoters. It is applicable to chiral substrates without loss of their optical purity. Copyright
- Yao, Haoyi,Yamamoto, Kana
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supporting information; experimental part
p. 1542 - 1545
(2012/09/08)
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- Study on 1,3,5-triazine chemistry in dehydrocondensation: Gauche effect on the generation of active triazinylammonium species
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The reaction of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) with various nitrogen-containing compounds, particularly tertiary amines (tert-amines), has been studied for the preparation of 2-(4,6-dimethoxy-1,3,5-triazinyl) trialkylammonium salts [DMT-Am(s)]. DMT-Ams derived from aliphatic tert-amines exhibited activity for the dehydrocondensation between a carboxylic acid and an amine to form an amide in a model reaction. Based on a conformational analysis of DMT-Ams and tert-amines by NMR and X-ray diffraction methods, we concluded that a β-alkyl group maintained in a gauche relationship with the nitrogen lone pair of tert-amines significantly hinders the approach of CDMT to the nitrogen. Thus, trimethylamine and quinuclidine without such alkyl groups readily react with CDMT whereas triethylamine, possessing two or three such gauche β-alkyl groups in the stable conformations, does not react at all. The theory of "gauche β-alkyl group effect" proposed here provides useful guidelines for the preparation of DMT-Ams possessing various tertiary amine moieties. An investigation of the dehydrocondensation activity of tert-amines in a CDMT/tert-amine system that involves in situ generation of DMT-Am, showed that the gauche effect of the β-alkyl group becomes quite pronounced; the yield of the amide decreases significantly with tert-amines possessing an unavoidable gauche β-alkyl group. Thus, the tert-amine/CDMT systems are useful for judging whether tert-amines can readily react with CDMT without isolation of DMT-Ams. The right approach! The structure-activity relationship of nitrogen-containing compounds including aliphatic tertiary amines in the reaction with 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) has been investigated (see scheme). The theory of "gauche β-alkyl group effect" proposed here provides useful guidelines for the preparation of triazine-based dehydrocondensation reagents (DMT-Ams) possessing various tertiary amine moieties. Copyright
- Kunishima, Munetaka,Ujigawa, Takae,Nagaoka, Yoshie,Kawachi, Chiho,Hioki, Kazuhito,Shiro, Motoo
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p. 15856 - 15867
(2013/01/16)
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- Ruthenium-catalyzed oxidation of alcohols into amides
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The synthesis of secondary amides from primary alcohols and amines has been developed using commercially available [Ru(p-cymene)CI2]2 with bis(diphenylphosphino)butane (dppb) as the catalyst.
- Watson, Andrew J.A.,Maxwell, Aoife C.,Williams, Jonathan M.J.
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supporting information; experimental part
p. 2667 - 2670
(2009/10/02)
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- PHENYL-CONTAINING N-ACYL AMINE AND AMINOACID DERIVATIVES, METHODS FOR THE PRODUCTION THEREOF, A PHARMACEUTICAL COMPOSITION AND THE USE THEREOF
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The present invention relates to novel phenyl-N-acyl derivatives of biogenic amines and amino acids of general formula (I) as cyclooxynease inhibitors, possessing analgetic and anti-inflammatory properties and devoid of side effects in particular ulcerogeneity and pro-spasmodic actions, as well as capability to potentiate effect of other analgetics, and possessing in addition antihypoxic, antidepressant and anti-Parkinsonistic action; as well as to the processes for the preparation novel and known phenyl-N-acyl derivatives of biogenic amines, to a pharmaceutical composition and to an agent comprising compounds of general formula (I) as well as to use thereof and a method of treating.
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Page/Page column 20
(2008/06/13)
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- IMPROVEMENTS IN OR RELATING TO COMPOUNDS FOR USE IN THE TREATMENT OF AIDS AND OTHER VIRAL DISEASES AND HIV-RELATED INFECTIONS AND COMPOSITIONS CONTAINING SUCH COMPOUNDS, METHODS OF TREATING SUCH DISEASES AND INFECTIONS AND METHODS OF MAKING SUCH COMPOUNDS AND COMPOSITIONS
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The present invention provides methods for treating Acquired Immunodeficiency Syndrome (AIDS) and other viral diseases and Human Immunodeficiency Virus (HIV) related infections by administering one or more compounds of formula I: wherein: the dotted line represents a single or a double bond; and R1 and R2 are the same or different and independently of each other represent - CH2OH, -CH2OR4, -CH(OH)CH3, -CH(OR4)CH3 or a group represented by the formula: or salts or hydrates thereof in a carrier which minimizes micellar formation or van der Waals attraction of molecules of said compound. The invention also provides S enantiomeric forms of such compounds which possess the ability to inhibit cell growth whilst being of low toxicity to such cells and methods of making such compounds.
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Page/Page column 26
(2008/06/13)
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- NOVEL COMPOUNDS FOR USE IN THE TREATMENT OF AUTOIMMUNE DISEASES, IMMUNO-ALLERGICAL DISEASES AND ORGAN OR TISSUE TRANSPLANTATION REJECTION
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The present invention provides compounds, pharmaceutical compositions and methods for treating, immuno-allergical diseases, autoimmune diseases, and organ or tissue rejection following transplantation.
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- Solid phase synthesis of amides using Mukaiyama's reagent
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A new solid-phase synthetic method using Mukaiyama's reagent under mild conditions is reported to prepare amides in high purity without purification after cleavage from the resins.
- Tao, Bin,Boykin, David W.
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- METHOD FOR STORING QUATERNARY AMMONIUM SALT
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A method of improving the stability of a quaternary ammonium salt and a method of efficiently preparing the quaternary ammonium salt having improved stability.
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- Solvent-free preparation of amides from acids and primary amines under microwave irradiation
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Synthesis of amides via pyrolysis of the salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free conditions within short times and appreciable yields under microwave activation. The evident specific non-thermal microwave effects are attributed to polarity increase during the course of the reaction, due to development of a dipole in the transition state.
- Perreux, Laurence,Loupy, André,Volatron, Fran?ois
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p. 2155 - 2162
(2007/10/03)
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- Formation of carboxamides by direct condensation of carboxylic acids and amines in alcohols using a new alcohol- and water-soluble condensing agent: DMT-MM
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Selective formation of carboxamides in an alcohol or water by an exceptionally convenient one-step procedure in which a condensing agent is simply added to a mixture of acids and amines has been achieved successfully by using a new condensing agent, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM). Activation of carboxylic acids by DMT-MM in the presence of amines and subsequent aminolysis of the resulting acyloxytriazine in alcoholic solvents occurred selectively and led to the formation of carboxamides in excellent yields. The rate of aminolysis of the acyloxytriazine intermediate can be estimated to be about 2×104 times greater than that of methanolysis. The amide/ester selectivity observed using DMT-MM was much larger than that obtained with DCC or EDC. Condensation of polar substrates, such as amino acid esters and their hydrochlorides, glucosamine hydrochloride, sodium acetate and dicarboxylic acids, proceeded successfully in MeOH, water or aqueous MeOH in good yields. The present reaction is technically quite simple and easy to achieve. It proceeds by simple mixing of acids, amines and DMT-MM without any additives, and the MeOH is readily removable by a rotary evaporator after completion of the reaction.
- Kunishima, Munetaka,Kawachi, Chiho,Hioki, Kazuhito,Terao, Keiji,Tani, Shohei
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p. 1551 - 1558
(2007/10/03)
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- 4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride: An efficient condensing agent leading to the formation of amides and esters
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4-(4,6-Dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) was quantitatively synthesized by the coupling of 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) and N- methylmorpholine (NMM) in THF, and characterized. Condensation of carboxylic acids and amines by DMTMM proceeded effectively in THF to give the corresponding amides in good yields. The corresponding esters can be obtained by esterification of carboxylic acids with DMTMM in methanol, ethanol, isopropyl alcohol, or t-butyl alcohol in the presence of NMM. The amount of alcohols can be reduced to a stoichiometric amount by conducting the reaction in THF. Since the reactions proceed under atmospheric conditions without drying of the solvent, and the co- product (4,6-dimethoxy-1,3,5-triazin-2(1H)-one) arising from DMTMM after condensation can be readily removed by extraction, this method is a very practical one.
- Kunishima, Munetaka,Kawachi, Chiho,Morita, Jun,Terao, Keiji,Iwasaki, Fumiaki,Tani, Shohei
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p. 13159 - 13170
(2007/10/03)
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