- Ammonia-borane as a Catalyst for the Direct Amidation of Carboxylic Acids
-
Ammonia-borane serves as an efficient substoichiometric (10%) precatalyst for the direct amidation of both aromatic and aliphatic carboxylic acids. In situ generation of amine-boranes precedes the amidation and, unlike the amidation with stoichiometric amine-boranes, this process is facile with 1 equiv of the acid. This methodology has high functional group tolerance and chromatography-free purification but is not amenable for esterification. The latter feature has been exploited to prepare hydroxyl- and thiol-containing amides.
- Ramachandran, P. Veeraraghavan,Hamann, Henry J.
-
supporting information
p. 2938 - 2942
(2021/05/04)
-
- Electron-Catalyzed Aminocarbonylation: Synthesis of α,β-Unsaturated Amides from Alkenyl Iodides, CO, and Amines
-
Aminocarbonylation of alkenyl iodides with CO and amines proceeded under heating to produce α,β-unsaturated amides in good yields (23 examples, 71% average yield). This catalyst-free method exhibited good functional-group tolerance, and open a straightforward access to functionalized acrylamides, as illustrated by the synthesis of Ilepcimide. A hybrid radical/ionic mechanism involving chain electron transfer is proposed for this transformation.
- Picard, Baptiste,Fukuyama, Takahide,Bando, Takanobu,Hyodo, Mamoru,Ryu, Ilhyong
-
supporting information
p. 9505 - 9509
(2021/12/09)
-
- Simple Synthesis of Amides via Their Acid Chlorides in Aqueous TPGS-750-M
-
The technology of surfactant chemistry is employed for amide bond construction via the reaction of acyl chlorides with amines in 2 wt % TPGS-750-M aqueous solution. Specifically, this highly efficient method enables a chromatography-free scalable process and recycling of the TPGS-750-M solution.
- Shi, Min,Ye, Ning,Chen, Wei,Wang, Hui,Cheung, Chiming,Parmentier, Michael,Gallou, Fabrice,Wu, Bin
-
supporting information
p. 1543 - 1548
(2020/11/23)
-
- N-Hydroxybenzimidazole as a structurally modifiable platform forN-oxyl radicals for direct C-H functionalization reactions
-
Methods for direct functionalization of C-H bonds mediated byN-oxyl radicals constitute a powerful tool in modern organic synthesis. While severalN-oxyl radicals have been developed to date, the lack of structural diversity for these species has hampered further progress in this field. Here we designed a novel class ofN-oxyl radicals based onN-hydroxybenzimidazole, and applied them to the direct C-H functionalization reactions. The flexibly modifiable features of these structures enabled facile tuning of their catalytic performance. Moreover, with these organoradicals, we have developed a metal-free approach for the synthesis of acyl fluoridesviadirect C-H fluorination of aldehydes under mild conditions.
- Hatanaka, Miho,Jiang, Julong,Maruoka, Keiji,Matsumoto, Akira,Sakamoto, Ryu,Sakurai, Shunya,Tsuzuki, Saori,Yoshii, Tomomi
-
p. 5772 - 5778
(2020/06/22)
-
- Efficient cleavage of tertiary amide bonds: Via radical-polar crossover using a copper(ii) bromide/Selectfluor hybrid system
-
A novel approach for the efficient cleavage of the amide bonds in tertiary amides is reported. Based on the selective radical abstraction of a benzylic hydrogen atom by a CuBr2/Selectfluor hybrid system followed by a selective cleavage of an N-C bond, an acyl fluoride intermediate is formed. This intermediate may then be derivatized in a one-pot fashion. The reaction proceeds under mild conditions and exhibits a broad substrate scope with respect to the tertiary amide moiety as well as to nitrogen, oxygen, and carbon nucleophiles for the subsequent derivatization. Mechanistic studies suggest that the present reaction proceeds via a radical-polar crossover process that involves benzylic carbon radicals generated by the selective radical abstraction of a benzylic hydrogen atom by the CuBr2/Selectfluor hybrid system. Furthermore, a synthetic application of this method for the selective cleavage of peptides is described. This journal is
- Maruoka, Keiji,Matsumoto, Akira,Wang, Zhe
-
p. 12323 - 12328
(2020/12/08)
-
- Graphene oxide: A convenient metal-free carbocatalyst for facilitating amidation of esters with amines
-
Herein, we report a graphene oxide (GO) catalyzed condensation of non-activated esters and amines, that can enable diverse amides to be synthesized from abundant ethyl esters forming only volatile alcohol as a by-product. GO accelerates ester to amide conversion in the absence of any additives, unlike other catalysts. A wide range of ester and amine substrates are screened to yield the respective amides in good to excellent yields. The improved catalytic activity can be ascribed to the oxygenated functionalities present on the graphene oxide surface which forms H-bonding with the reactants accelerating the reaction. Improved yields and a wide range of functional group tolerance are some of the important features of the developed protocol.
- Patel, Khushbu P.,Gayakwad, Eknath M.,Shankarling, Ganapati S.
-
p. 2661 - 2668
(2020/02/20)
-
- An Efficient Solvent-Free Microwave-Assisted Synthesis of Cinnamamides by Amidation Reaction Using Phenylboronic Acid/Lewis Base Co-catalytic System
-
A microwave-assisted dehydrative amide condensation reaction is reported as an efficient access to cinnamamide derivatives under solvent-free conditions. This protocol between conjugated carboxylic acids and amines is based on the use of a co-catalytic system, including the presence of the commercially available phenylboronic acid and 4-(N, N-dimethylamino)pyridine N-oxide (DMAPO), with a complete chemoselectivity in favor of the corresponding α,β-unsaturated amides. The implementation of the reaction needs no special precaution, and less reactive amines, such as substituted anilines, are also efficient under these conditions. A series of novel conjugated amides have been evaluated for their cytotoxic activities against several human cancer cell lines.
- Carboni, Bertrand,Khaldoun, Khadidja,Safer, Abdelmounaim,Saidi-Besbes, Salima,Carreaux, Fran?ois,Le Guével, Rémy
-
p. 3891 - 3900
(2019/10/11)
-
- Rapid access to cinnamamides and piper amides: Via three component coupling of arylaldehydes, amines, and Meldrum's acid
-
A practical method for the synthesis of cinnamamides and piper amides via a conceptually novel three component reaction of aldehydes, amines and Meldrum's acid has been reported. The reaction proceeds under operationally simple conditions without the aid of coupling reagents, oxidants, or catalysts, which are essential for the preparation of cinnamamides/piper amides via known methods. The formation of undesired chemical wastes that generally originate from the use of coupling reagents, oxidants, or catalysts has been avoided to make this reaction more atom economical.
- Ghosh, Santanu,Jana, Chandan K.
-
supporting information
p. 5803 - 5807
(2019/11/11)
-
- Mild, Metal-Free and Protection-Free Transamidation of N-Acyl-2-piperidones to Amino Acids, Amino Alcohols and Aliphatic Amines and Esterification of N-Acyl-2-piperidones
-
Amides are indispensable building blocks of biological systems, pharmaceuticals, and materials. We report a highly selective method for the synthesis of amides via transamidation process. Transamidation of N-acyl-2-piperidones with a broad range of amines is demonstrated under exceedingly mild and metal-free reaction condition that relies on the amide bond twist to weaken the amidic resonance. Transamidation proceeds under the neat condition at room temperature, in short reaction times (30–90 min) with good yields. Considerable variation is tolerated with both amine and imide substrates. Of note, amines bearing carboxylic acids (glycine and serine) and hydroxyl groups (dopamine, tyramine, etc.) are well tolerated which are otherwise problematic under the metal-catalyzed protocol. Our current method is applicable for transamidation of both alkyl and aryl-N-acyl-2-piperidones. The practical value of the method is highlighted by the synthesis of four natural product amide alkaloids in high yields under mild reaction conditions. In the absence of nucleophilic amines, N-acyl-2-piperidones undergoes esterification with EtOH at elevated temperature. Single crystal X-ray analysis of an N-acyl-2-piperidone shows amide bond twist, τ = –20.39° and pyramidalization, χN = –11.73°. This weakens the amidic conjugation and might be the factor controlling the reactivity and selectivity of these imides. We envision that the N-acyl-2-piperidone scaffold would be useful in the synthesis of pharmaceuticals and materials.
- Subramani, Muthuraman,Rajendran, Saravana Kumar
-
p. 3677 - 3686
(2019/06/08)
-
- Air-stable Bis(pentamethylcyclopentadienyl) Zirconium Perfluorooctanesulfonate as an Efficient and Recyclable Catalyst for the Synthesis of N-substituted Amides
-
Bis(pentamethylcyclopentadienyl) zirconium perfluorooctanesulfonate is an air-stable and water-tolerant Lewis acid. This complex exhibited good thermal stability and high solubility in polar organic solvents. The compound showed relatively strong acidity, with an acid strength of 0.8Ho≤3.3, and high catalytic efficiency for the synthesis of N-substituted amides via the reaction of carboxylic acids with amines, the Ritter reaction of nitriles with alcohols, and the amination of alcohols with amides. Moreover, the complex had good reusability. This catalytic system affords a simple and efficient way to synthesize N-substituted amides.
- Li, Ningbo,Wang, Lingxiao,Zhang, Liting,Zhao, Wenjie,Qiao, Jie,Xu, Xinhua,Liang, Zhiwu
-
p. 3532 - 3538
(2018/08/01)
-
- Enantioselective Epoxidation of Electron-Deficient Alkenes Catalyzed by Manganese Complexes with Chiral N4 Ligands Derived from Rigid Chiral Diamines
-
A series of tetradentate sp2N/sp3N hybrid chiral N4 ligands derived from rigid chiral diamines were synthesized, which enabled the first manganese-catalyzed enantioselective epoxidation of electron-deficient alkenes with hydrogen peroxide (H2O2) as an oxidant. The reaction furnishes enantiomerically pure epoxy amides, epoxy ketones as well as epoxy esters in good yields and excellent enantioselectivities (up to 99.9% ee) with lower catalyst loading. Preliminary studies on structure–activity relationship demonstrated that maintaining comparatively lower electron-donating ability of the sp3N and relatively higher electron-donating ability of sp2N of the N4 ligands is beneficial to getting higher activity and selectivity, thus providing us a new view to understand epoxidation with H2O2. (Figure presented.).
- Chen, Xiangning,Gao, Bao,Su, Yijin,Huang, Hanmin
-
supporting information
p. 2535 - 2541
(2017/08/16)
-
- General and Efficient Intermolecular [2+2] Photodimerization of Chalcones and Cinnamic Acid Derivatives in Solution through Visible-Light Catalysis
-
[2+2] Photocycloaddition, for example, the dimerization of chalcones and cinnamic acid derivatives, is a unique strategy to construct cyclobutanes, which are building blocks for a variety of biologically active molecules and natural products. However, most attempts at the above [2+2] addition have focused on solid-state, molten-state, or host–guest systems under ultraviolet-light irradiation in order to overcome the competition of facile geometric isomerization of nonrigid olefins. We report a general and simple method to realize the intermolecular [2+2] dimerization reaction of these acyclic olefins to construct cyclobutanes in a highly regio- and diastereoselective manner in solution under visible light, which provides an efficient solution to a long-standing problem.
- Lei, Tao,Zhou, Chao,Huang, Mao-Yong,Zhao, Lei-Min,Yang, Bing,Ye, Chen,Xiao, Hongyan,Meng, Qing-Yuan,Ramamurthy, Vaidhyanathan,Tung, Chen-Ho,Wu, Li-Zhu
-
supporting information
p. 15407 - 15410
(2017/11/13)
-
- Diphenylsilane as a coupling reagent for amide bond formation
-
A simple procedure for amide bond formation using diphenylsilane as a coupling reagent is described. This methodology enables the direct coupling of carboxylic acids with primary and secondary amines, releasing only hydrogen and a siloxane as by-products. Only one equivalent of each partner is needed, providing a more sustainable amidation method producing minimal wastes. This methodology was also extended to the synthesis of peptides and lactams by addition of Hünig's base (DIPEA) and 4-dimethylaminopyridine (DMAP).
- Sayes, Morgane,Charette, André B.
-
supporting information
p. 5060 - 5064
(2017/11/09)
-
- A One-Pot, fast, and efficient amidation of carboxylic acids, α-amino acids and sulfonic acids using pph3/n-chlorobenzotriazole system
-
Triphenylphosphine (PPh3)/N-chlorobenzotriazole (NCBT), and amine (primary and secondary aliphatic amines and also substituted anilines) in CH2Cl2 efficiently converted carboxylic acids, α-amino acids, and sulfonic acids to the corresponding amides and sulfonamides at room temperature. Good to excellent yields, inexpensive, and fast reaction conditions are the important features of this procedure.
- Rouhi-Saadabad, Hamed,Akhlaghinia, Batool
-
p. 1703 - 1714
(2015/09/15)
-
- Design, synthesis, and evaluation of caffeic acid amides as synergists to sensitize fluconazole-resistant Candida albicans to fluconazole
-
A series of caffeic acid amides were designed, synthesized, and their synergistic activity with fluconazole against fluconazole-resistant Candida albicans was evaluated in vitro. The title caffeic acid amides 3-30 except 26 exhibited potent activity, and the subsequent SAR study was conducted. Compound 3, 5, 21, and 34c, at a concentration of 1.0 μg/ml, decreased the MIC80 of fluconazole from 128.0 μg/ml to 1.0-0.5 μg/ml against the fluconazole-resistant C. albicans. This result suggests that the caffeic acid amides, as synergists, can sensitize drug-resistant fungi to fluconazole. The SAR study indicated that the dihydroxyl groups and the amido groups linking to phenyl or heterocyclic rings are the important pharmacophores of the caffeic acid amides.
- Dai, Li,Zang, Chengxu,Tian, Shujuan,Liu, Wei,Tan, Shanlun,Cai, Zhan,Ni, Tingjunhong,An, Maomao,Li, Ran,Gao, Yue,Zhang, Dazhi,Jiang, Yuanying
-
-
- Catalyst and method for producing the same
-
PROBLEM TO BE SOLVED: To provide a method for producing an amide compound from a primary alcohol and at least one selected from a primary amine, a secondary amine and derivatives of those under relatively mild conditions with high selectivity and a high conversion ratio.SOLUTION: A method for producing an amide compound comprises a step of obtaining the amide compound from a primary alcohol and at least one selected from a primary amine, a secondary amine and derivatives of those, in the presence of a catalyst comprising a carrier formed by crosslinking a crosslinkable functional group of a styrene-based polymer having a side chain containing the crosslinkable functional group, and a nanosize cluster and carbon black supported on the carrier, wherein the nanosize cluster is at least one selected from a nanosize gold cluster and a nanosize cluster of gold and at least one group 8 metal selected from iron, cobalt and nickel.
- -
-
Paragraph 0073; 0075; 0080
(2016/11/07)
-
- Lanthanum(III) triflate catalyzed direct amidation of esters
-
Lanthanum trifluoromethanesulfonate is an effective single-component catalyst for synthesizing a variety of amides directly from esters and amines under mild conditions. Highly selective amidation of esters and amines, as well as catalyst-controlled amidation of esters, demonstrated the effectiveness of the catalyst system.
- Morimoto, Hiroyuki,Fujiwara, Risa,Shimizu, Yuhei,Morisaki, Kazuhiro,Ohshima, Takashi
-
supporting information
p. 2018 - 2021
(2014/05/06)
-
- Amides in one pot from Carboxylic Acids and Amines via Sulfinylamides
-
An efficient method has been developed for the direct amidification of carboxylic acids via sulfinylamides preformed in situ by the reaction of pure amines with prop-2- ene-1-sulfinyl chloride. The method can be applied to aliphatic acids, including pivalic acid, aromatic acids, and primary and secondary amines. It is compatible with acids bearing unprotected alcohol, phenol, and ketone moieties and applicable to the synthesis of peptides. It does not induce their a-epimerization.
- Bai, Jianfei,Zambron, Bartosz K.,Vogel, Pierre
-
supporting information
p. 604 - 607
(2014/04/03)
-
- Palladium/copper-catalyzed oxidative arylation of terminal alkenes with aroyl hydrazides
-
An unprecedented oxidative arylation reaction of terminal alkenes with simple aroyl hydrazides has been developed under aerobic conditions for the stereoselective synthesis of 1,2-disubstituted alkenes. A range of aroyl hydrazides underwent palladium/copper-catalyzed oxidative Mizoroki-Heck reaction with terminal alkenes open to air in a 1:1 mixture of dimethyl sulfoxide and acetonitrile to give structurally diverse 1,2-disubstituted alkenes in moderate to excellent yields with excellent regio- and E-selectivity. The reaction tolerated a wide variety of functional groups, such as alkoxy, hydroxy, amino, fluoro, chloro, bromo, cyano, nitro, ester, amide, imide, phosphine oxide, and sulfone groups, and, moreover, molecular oxygen and dimethyl sulfoxide were demonstrated to serve as terminal oxidants. This study provides a useful method for the stereoselective synthesis of 1,2-disubstituted alkenes through direct transformation of the vinylic Ci-H bonds in terminal alkenes. Cross-coupling: An oxidative arylation reaction of terminal alkenes with simple aroyl hydrazides has been developed in the presence of a PdCl2/CuI catalyst under aerobic conditions to give a range of structurally diverse 1,2-disubstituted alkenes in moderate to excellent yields with excellent regio- and E-selectivity (see scheme; r.s.=regioselectivity).
- Zhang, Yong-Gang,Liu, Xiang-Lei,He, Zeng-Yang,Li, Xi-Ming,Kang, Hong-Jian,Tian, Shi-Kai
-
supporting information
p. 2765 - 2769
(2014/03/21)
-
- The triflic acid-mediated cyclisation of N-benzyl-cinnamamides
-
N-Benzyl-cinnamamides cyclise with triflic acid to form 5-aryl-benzazepinones and/or cinnamamides.
- King, Frank D.,Caddick, Stephen
-
supporting information
p. 487 - 491
(2013/07/27)
-
- Facile preparation of amides from carboxylic acids and amines with ion-supported Ph3P
-
Ion-supported Ph3P, 4-(diphenylphosphino)benzyltrimethylammonium bromide (IS-Ph3P), could be used for the facile amidation of a wide range of carboxylic acids with amines in the presence of bromotrichloromethane to provide the corresponding amides in good yields. In the present reaction, the desired amides were obtained in good yields with high purity by simple extraction of the reaction mixture with diethyl ether or chloroform and subsequent removal of the solvent from the extract. Moreover, ion-supported Ph3PO (IS-Ph3PO), which was a co-product derived from IS-Ph3P in the present reductive condensation, was recovered in high yield and could be reduced to IS-Ph3P for reuse in the same amidation of carboxylic acid.
- Kawagoe, Yuhsuke,Moriyama, Katsuhiko,Togo, Hideo
-
p. 3971 - 3977
(2013/06/27)
-
- Palladium-catalyzed fluorocarbonylation using N-formylsaccharin as CO source: General access to carboxylic acid derivatives
-
N-Formylsaccharin, an easily accessible crystalline compound, has been employed as an efficient CO source in Pd-catalyzed fluorocarbonylation of aryl halides to afford the corresponding acyl fluorides in high yields. The reactions use a near-stoichiometric amount of the CO source (1.2 equiv) and tolerate diverse functional groups. The acyl fluorides obtained could be readily transformed into various carboxylic acid derivatives such as carboxylic acid, esters, thioesters, and amides in a one-pot procedure.
- Ueda, Tsuyoshi,Konishi, Hideyuki,Manabe, Kei
-
supporting information
p. 5370 - 5373
(2013/11/06)
-
- The triflic acid-mediated cyclisation of N-benzylcinnamanilides
-
N-Benzylcinnamanilides cyclise with triflic acid to form 1-benzyl-4-aryl-2,4-dihydro-1H-quinolin-2-ones and 2,5-diaryl-benzazepin-3-ones. The product ratio is determined by the preferred orientation of the amide and by the electronics of the substituents. With ortho-substituted anilides, N-debenzylation also occurs to give 4-aryl-2,4-dihydro-1H-quinoline-2-ones.
- King, Frank D.,Caddick, Stephen
-
p. 8592 - 8601
(2013/09/12)
-
- Palladium-free aminocarbonylation of aryl, benzyl, and styryl iodides and bromides by amines using Mo(CO)6 and norbornadiene
-
A simple and efficient method is described for aminocarbonylation of aryl, benzyl, and styryl iodides and bromides using the in situ generated molybdenum tetracarbonyl norbornadiene [Mo(CO)4(nbd)] complex as a suitable source of carbon monoxide.
- Iranpoor, Nasser,Firouzabadi, Habib,Motevalli, Somayeh,Talebi, Mohsen
-
p. 418 - 426
(2013/01/15)
-
- Stereoselective olefination and regiospecific vicinal difunctionalization of imines with α-(benzothiazol-2-ylsulfonyl) carbonyl compounds
-
Depending on their structures, imines are able to undergo either olefination or vicinal difunctionalization with various α-(benzothiazol-2- ylsulfonyl) carbonyl compounds in the absence of external bases. The olefination reaction of aromatic imines with α-(benzothiazol-2-ylsulfonyl) carbonyl compounds proceeds smoothly in tetrahydrofuran at 70 °C to give structurally diverse α,β-unsaturated esters, amides, and ketones in good to excellent yields and with extremely high (E) selectivity. In contrast, the carbon-nitrogen double bonds of cyclic imines and the carbon-carbon double bonds of α,β-unsaturated imines are subjected to regiospecific vicinal difunctionalization with α-(benzothiazol-2-ylsulfonyl) carbonyl compounds under the same reaction conditions to give a variety of benzothiazole derivatives in good to excellent yields. It is noteworthy that the benzothiazole moiety is present in a number of antitumor agents and bioluminescent molecules. In addition, plausible reaction pathways have been proposed to account for these transformations, and these are substantially supported by ESI-MS analysis of the reaction mixtures.
- Shao, You-Dong,Wu, Xue-Song,Tian, Shi-Kai
-
p. 1590 - 1596
(2012/05/07)
-
- NHC-catalyzed C-O or C-N bond formation: Efficient approaches to α,β-unsaturated esters and amides
-
Simple and efficient NHC-catalyzed transformations of bromoenal or α,β-dibromoenal into α,β-unsaturated esters or amides with high stereoselectivity through C-O or C-N bond formation have been demonstrated. The NHC-catalyzed processes occur under mild con
- Zhang, Bo,Feng, Peng,Cui, Yuxin,Jiao, Ning
-
supporting information; experimental part
p. 7280 - 7282
(2012/07/28)
-
- Sulfated tungstate: A new solid heterogeneous catalyst for amide synthesis
-
Amide formation avoiding poor atom economy reagents is a priority area. We have synthesized sulfated tungstate as a new reusable and environmentally benign heterogeneous catalyst for direct amide formation between carboxylic acid and amine. It has potential for large scale applications.
- Chaudhari, Pramod S.,Salim, Suresh D.,Sawant, Ravindra V.,Akamanchi, Krishnacharya G.
-
supporting information; experimental part
p. 1707 - 1710
(2011/02/23)
-
- Simple synthesis of amides and weinreb amides Using PPh3 or PolymerSupported PPh3 and Iodine
-
The combination of PPh3/I2 has been shown to be effective for the conversion of a range of carboxylic acids into secondary, tertiary, and Weinreb amides. Simplification of the procedure was possible with the use of polymer-supported PPh3/ I2. Weinreb amides produced with the use of polymer-supported PPh3 could be filtered through a short silica gel plug and used in further transformations. Thus, the use of polymer-supported PPh3 offers potential applicability to diversityoriented reactions. Formal total syntheses of apocynin and pratosine, as well as syntheses of anhydrolychorinone and hippadine, have been achieved through the use of this amide-forming method. An attempt has been made to gain insight into this reaction.
- Kumar, Amit,Akula, Hari Kiran,Lakshman, Mahesh K.
-
experimental part
p. 2709 - 2715
(2010/08/05)
-
- Mo(CO)6-mediated carbamoylation of aryl halides
-
A simple method for the synthesis of amides has been developed by molybdenum-mediated carbamoylation of aryl halides. Whereas the conventional palladium-catalyzed three-component coupling reaction requires a large excess of gaseous carbon monoxide, the incorporation of carbon monoxide in this Mo-mediated carbamoylation reaction is so efficient that it requires only a slight excess amount of carbon monoxide in the form of its molybdenum complex, Mo(CO)6. The reaction is applicable for the synthesis of a wide variety of not only secondary and tertiary amides but also primary amides by using aqueous ammonia.
- Ren, Wei,Yamane, Motoki
-
experimental part
p. 8410 - 8415
(2011/02/23)
-
- Molybdenum-mediated carbonylation of aryl halides with nucleophiles using microwave irradiation
-
Figure Presented. A new, efficient, and practical molybdenum-mediated carbonylation of aryl and heteroaryl halides with a variety of nucleophiles is described using microwave irradiation. A range of reactions illustrating the wide scope of this chemistry were carried out and proceeded in good to excellent yields.
- Roberts, Bryan,Liptrot, David,Alcaraz, Lilian,Luker, Tim,Stocks, Michael J.
-
supporting information; experimental part
p. 4280 - 4283
(2010/11/04)
-
- Palladium(II)-catalyzed catalytic aminocarbonylation and alkoxycarbonylation of terminal alkynes: Regioselectivity controlled by the nucleophiles
-
The aminocarbonylation and alkoxycarbonylation reactions of terminal alkynes took place smoothly and efficiently using a catalyst system Pd(OAc) 2-dppb-p-TsOH-CH3CN-CO under relatively mild experimental conditions. The catalytic system was tested and optimized using two different nucleophiles: alcohols and amines. Phenylacetylene (1a) was considered as an alkyne along with diisobutylamine (2b1) andmethanol (2c1) as nucleophiles. The results showed significant differences in the conversion of 1a and in the selectivity towards the gem or trans unsaturated esters or amides with these nucleophiles. The effects of the type of palladium catalysts, the type of ligands, the amount of dppb and the solvents were carefully studied. With diisobutylamine (2b1), excellent regioselectivity towards the 2-acrylamides (gem isomer, 3ab1) was almost always observed, while trans-α,β-unsaturated esters 4ac1 was the predominant product with methanol (2c1) as a nucleophile. This remarkable sensitivity in the selectivity of the reaction indicates two different possible mechanistic pathways for these carbonylation reactions. Copyright
- Suleiman, Rami,Tijani, Jimoh,El Ali, Bassam
-
experimental part
p. 38 - 46
(2010/10/02)
-
- Oxidative amidation and azidation of aldehydes by NHC catalysis
-
Figure presented N-Heterocyclic carbene catalyzed oxidative amidations of various aldehydes to the corresponding hexafluoroisopropylesters by using the readily available organic oxidant A are described. The hexafluoroisopropylesters prepared in situ are shown to be highly useful active esters for amide bond formation. In addition, oxidative azidation of aldehydes is presented. These mild organocatalytic processes do not use any transition metal.
- De Sarkar, Suman,Studer, Armido
-
supporting information; experimental part
p. 1992 - 1995
(2010/07/10)
-
- Carbamoylation of aryl halides by molybdenum or tungsten carbonyl amine complexes
-
When aryl halide is treated with molybdenum carbonyl amine complex in the presence of base, carbamoylation proceeds to give amide in good yield. The proposed mechanism involves oxidative addition of aryl halide to molybdenum(0) complex, migratory insertio
- Ren, Wei,Yamane, Motoki
-
supporting information; experimental part
p. 3017 - 3020
(2010/07/05)
-
- Trimethylaluminium mediated amide bond formation in a continuous flow microreactor as key to the synthesis of rimonabant and efaproxiral
-
A safe, functional-group-tolerant and high-throughput version of the trimethylaluminium mediated amide bond formation reaction has been developed in a microreactor system; rimonabant and efaproxiral were prepared to illustrate the utility of the method. The Royal Society of Chemistry.
- Gustafsson, Tomas,Ponten, Fritiof,Seeberger, Peter H.
-
p. 1100 - 1102
(2008/09/21)
-
- Efficient synthesis of new N-benzyl- or N-(2-furylmethyl)cinnamamides promoted by the 'green' catalyst boric acid, and their spectral analysis
-
New N-benzyl- or N-(2-furylmethyl)cinnamamides were prepared in good to excellent yields by amidation reactions between cinnamic acid and benzylamines or (2-furylmethyl)amine in the presence of 5 mol% boric acid. All the cinnamamides were characterized by IR and 1H and 13C NMR spectroscopy. Georg Thieme Verlag Stuttgart.
- Barajas, Jose Gregorio Hernandez,Mendez, Leonor Yamile Vargas,Kouznetsov, Vladimir V.,Stashenko, Elena E.
-
p. 377 - 382
(2008/09/20)
-
- Carboxamidation of carboxylic acids with 1-tert-butoxy-2-tert-butoxycarbonyl-1,2-dihydroisoquinoline (BBDI) without bases
-
Formation of carboxamides of a variety of carboxylic acids with the coupling reagent BBDI is described. This procedure permits a one pot and simple operation without the need of any bases and no base was?required for even use of amine hydrochlorides. In addition, an approach to BBDI-catalyzed carboxamidation is examined.
- Saito, Yukako,Ouchi, Hidekazu,Takahata, Hiroki
-
experimental part
p. 11129 - 11135
(2009/04/11)
-
- Oxidation of aliphatic α,β-unsaturated aldimines to amides specifically by oxone with AlCl3
-
α,β-Unsaturated aldimines were specifically oxidized to amides with Oxone in the presence of AlCl3 as a Lewis acid in CH2Cl2. No migration of aryl group occurred in the rearrangement reaction. Copyright Taylor & Francis Group, LLC.
- Lu, Zhou,Peng, Lijun,Wu, Wentao,Wu, Longmin
-
p. 2357 - 2366
(2008/09/21)
-
- New boron(III)-catalyzed amide and ester condensation reactions
-
In 1996, we reported that benzeneboronic acids bearing electron-withdrawing groups at the meta- or para-position are highly effective catalysts for the amide condensation reaction in less-polar solvents. In this paper, we report that N-alkyl-4-boronopyridinium halides are more effective catalysts than the previous ones in more polar solvents. N-Alkyl-4-boronopyridinium halides are effective not only for amide condensation between equimolar mixtures of carboxylic acids and amines but also for the esterification of α-hydroxycarboxylic acids in alcohol solvents. Furthermore, perchlorocatecholborane is more effective than areneboronic acids for the amide condensation of sterically demanding carboxylic acids. In addition, Lewis acid-assisted Br?nsted acid (LBA), which is prepared from a 1:2 M mixture of boric acid and tetrachlorocatechol, is effective for the Ritter reaction from alcohols and nitriles to amides.
- Maki, Toshikatsu,Ishihara, Kazuaki,Yamamoto, Hisashi
-
p. 8645 - 8657
(2008/02/08)
-
- Phenylsilane as an active amidation reagent for the preparation of carboxamides and peptides
-
The use of phenylsilane as a mild coupling reagent for amidation reactions is reported. Applicability to both solution- and solid-phase chemistry has been demonstrated for a variety of amines and carboxylic acids.
- Ruan, Zheming,Lawrence, R. Michael,Cooper, Christopher B.
-
p. 7649 - 7651
(2007/10/03)
-
- Some chemical properties of 2,3-dihydro-4H-[1,3]thiazino[3,2-a] benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4- ones
-
We have studied the reaction of 2,3-dihydro-4H-[1,3]thiazino[3,2-a] benzimidazol-4-one and 2-aryl-2,3-dihydro-4H-[1,3]thiazino[3,2-a]benzimidazol-4- ones with amines, alkylating reagents, and hydrogen peroxide. We have shown that the presence of an aryl substituent at the 2 position of [1,3-thiazino[3,2-a] benzimidazol-4-ones has a substantial effect on the direction of the reactions. 2006 Springer Science+Business Media, Inc.
- Britsun,Esipenko,Lozinskii
-
p. 396 - 402
(2008/02/04)
-
- N-alkyl-4-boronopyridinium salts as thermally stable and reusable amide condensation catalysts
-
(Chemical Equation Presented) N-Alkyl-4-boronopyridinium salts are highly effective and reusable catalysts for the dehydrative amide condensation reaction between equimolar mixtures of carboxylic acids and amines. N- Alkylboronopyridinium salts are thermally stabilized in the order N-alkyl-2-boronopyridinium salt ? N-alkyl-3-boronopyridinium salt N-alkyl-4-boronopyridinium salt. Homogeneous catalysts, such as 4-borono-N-methylpyridinium iodide, are more effective in the presence of ionic liquid and can be recovered by extraction with ionic liquid. In contrast, heterogeneous catalysts, such as polystyrene-bound 4-boronopyridinium salts, are effective even in the absence of ionic liquid and can be recovered by filtration.
- Maki, Toshikatsu,Ishihara, Kazuaki,Yamamoto, Hisashi
-
p. 5043 - 5046
(2007/10/03)
-
- Aminolysis of 2-aryl-5-R-5,6-dihydro-7H-[1,2,4]triazolo[5,1-b]1,3]thiazin- 7-ones
-
We have established that the products of aminolysis of 2-aryl-5-R-5,6- dihydro-7H-[1,2,4]triazolo-[5,1-b][1,3] thiazin-7-ones in boiling ethanol are 3-R-3-(5-aryl-4H-1,2,4-triazol-3-ylsulfanyl)-propanamides, and at 180°C-210°C (depending on the structure of the substituent R): 3-phenyl-4,5-dihydro-1H-1,2,4-triazoline-5-thione and 3-arylacrylamides or 3-(3-aryl-5-thioxo-4,5-dihydro-1H-1,2,4-triazol-1-yl)propanamides. 2005 Springer Science+Business Media, Inc.
- Britsun,Esipenko,Pirozhenko,Lozinskii
-
p. 1334 - 1338
(2007/10/03)
-
- Synthesis of β-monosubstituted α,β-unsaturated amides with z-selectivity using diphenylphosphonoacetamides
-
The utility of diphenylphosphonoacetamides [(PhO)2P(O)CH 2CONRR′] as Horner-Wadsworth-Emmons reagents was examined with five different patterns of substitution upon the amide nitrogen atom (2a: R, R′ = CH2Ph; 2b: R = CH2Ph, R′ = H; 2c: R = Me, R′ = OMe; 2d: R, R′ = Ph; 2e: R, R′ = (CH2) 4). The reaction of 2a was found to be Z-selective for aromatic aldehydes with selectivities up to 95:5. Reagent 2b led to reasonable selectivity for both benzaldehyde (85:15) and 3-phenylpropionaldehyde (87:13), while 2c was somewhat effective for only the latter alkyl aldehyde (83:17). Compounds 2d and 2e exhibited slightly lower selectivities compared with 2a.
- Kojima, Satoshi,Hidaka, Tsugihiko,Ohba, Yuko
-
p. 515 - 523
(2007/10/03)
-
- A novel solid-phase chlorinating reagent for the synthesis of acyl chlorides
-
Cyanuric chloride was loaded onto a modified Wang resin, which was successfully used to convert carboxylic acids to their corresponding acyl chlorides. The formation of acyl chlorides were confirmed by condensation with various amines or alcohols to form the corresponding amides or esters.
- Luo, Guanglin,Xu, Li,Poindexter, Graham S.
-
p. 8909 - 8912
(2007/10/03)
-
- Catalytic asymmetric epoxidation of α,β-unsaturated amides: Efficient synthesis of β-aryl α-hydroxy amides using a one-pot tandem catalytic asymmetric epoxidation - Pd-catalyzed epoxide opening process
-
The catalytic asymmetric epoxidation of α,β-unsaturated amides using Sm-BINOL-Ph3As=O complex was succeeded. Using 5-10 mol % of the asymmetric catalyst, a variety of amides were epoxidized efficiently, yielding the corresponding α,β-epoxy amides in up to 99% yield and in more than 99% ee. Moreover, the novel one-pot tandem process, one-pot tandem catalytic asymmetric epoxidation-Pd-catalyzed epoxide opening process, was developed. This method was successfully utilized for the efficient synthesis of β-aryl α-hydroxy amides, including β-aryllactyl-leucine methyl esters. Interestingly, it was found that beneficial modifications on the Pd catalyst were achieved by the constituents of the first epoxidation, producing a more suitable catalyst for the Pd-catalyzed epoxide opening reaction in terms of chemoselectivity. Copyright
- Nemoto, Tetsuhiro,Kakei, Hiroyuki,Gnanadesikan, Vijay,Tosaki, Shin-Ya,Ohshima, Takashi,Shibasaki, Masakatsu
-
p. 14544 - 14545
(2007/10/03)
-
- Development and synthesis of an arylboronic acid-based solid-phase amidation catalyst
-
A polystyrene-bound pyridineboronic acid was synthesized and shown to be an efficient, easily recoverable and reusable amidation catalyst.
- Latta,Springsteen,Wang
-
p. 1611 - 1613
(2007/10/03)
-
- Desulfonylation of amides using tributyltin hydride, samarium diiodide or zinc/titanium tetrachloride. A comparison of methods
-
Deprotection of N-sulfonylated amides can be achieved by reaction with Bu3SnH, SmI2 or TiCl4/Zn. All three methods gave good yields (typically >60%) when using N-benzoyl or related amides while the corresponding N~acetyl derivatives proved to be inert to deprotection under the same reaction conditions. The mechanistic implications of this are discussed. (C) 2000 Elsevier Science Ltd.
- Knowles, Haydn S.,Parsons, Andrew F.,Pettifer, Robert M.,Rickling, Stéphane
-
p. 979 - 988
(2007/10/03)
-
- New transformations from a 3-silyloxy 2-aza-1,3-diene: Consecutive Zr- mediated retro-Brook rearrangement and reactions with electrophiles
-
A one-pot procedure for the transformation of the title compound to α- functionalized (silylated) and α,β-unsaturated secondary amides was described. The following steps were involved: a Zr-mediated retro-Brook rearrangement, selective deprotonation with n-BuLi on the organometallic intermediate, and trapping with electrophiles including alkyl and acyl halides and aldehydes. The electrophilic addition step occurred at a stabilized α-silyl carbanion center without affecting the near transition metal residue. In the case of aldehydes, the Peterson alkenation reaction took place on the transition metal complex in a highly stereoselective way. (C) 2000 Elsevier Science Ltd.
- Gandon, Vincent,Bertus, Philippe,Szymoniak, Jan
-
p. 4467 - 4472
(2007/10/03)
-
- A novel carbonylative decomplexation of alkyne-dicobalt hexacarbonyls: Hyrocarbamoylation of alkynes
-
A novel carbonylative decomplexation of alkyne-dicobalt hexacarbonyls, i.e. hydrocarbamoylation of alkynes, was carried out by reaction of the complexes with 10 equiv, of primary and secondary amines.
- Sugihara, Takumichi,Okada, Yoshinari,Yamaguchi, Masahiko,Nishizawa, Mugio
-
p. 768 - 770
(2007/10/03)
-