- Pd-Catalyzed Oxidative Aminocarbonylation of Arylboronic Acids with Unreactive Tertiary Amines via C-N Bond Activation
-
An efficient synthesis of tertiary amides from aryl boronic acids and inert tertiary amines through the oxidative carbonylation via C(sp3)-N bond activation is presented. This protocol significantly restricts the homocoupling biarylketone product. It involves the use of a homogeneous PdCl2/CuI catalyst and a heterogeneous Pd/C based catalyst, which promotes C(sp3)-N bond activation of tertiary amines with aryl boronic acids. This process represents a ligand-free, base-free, and recyclable catalyst along with an ideal oxidant like molecular oxygen.
- Kolekar, Yuvraj A.,Bhanage, Bhalchandra M.
-
p. 14028 - 14035
(2021/05/29)
-
- Pd-Catalyst Containing a Hemilabile P,C-Hybrid Ligand in Amino Dicarbonylation of Aryl Halides for Synthesis of α-Ketoamides
-
The amino dicarbonylation of aryl halides affording α-ketoamides with Pd catalysts is highly dependent on the stereoelectronic properties of the involved ligands. Ionic diphosphine ligand L4 can serve as precursor of a hemilabile P,C (phosphine, carbene)-hybrid ligand to form a stable Pd(II)-complex, Pd-L4. In contrast, analogues L1-L3 with a similar 1-(thiophen-3-yl)-benzimidazolyl skeleton behave as typical (mono/di)phosphines. The catalytic system resulting from the complexation of PdCl2(MeCN)2 and L4 exhibits good catalytic performance in terms of aryl iodides conversion (81-95%) and α-ketoamide selectivity (80-91%), as well as the available recyclability in the RTIL of [Bpy]BF4. The in situ FT-IR analysis reveals that the PdCl2(MeCN)2-L4 catalytic system favors the amino dicarbonylation toward α-ketoamides according to the proposed mechanism of cycle I, which involves two independent CO-insertion steps.
- Yang, Shu-Qing,Yao, Yin-Qing,Chen, Xiao-Chao,Lu, Yong,Zhao, Xiao-Li,Liu, Ye
-
p. 1032 - 1041
(2021/05/07)
-
- Mechanochemical Palladium-Catalyzed Carbonylative Reactions Using Mo(CO)6
-
Esters and amides were mechanochemically prepared by palladium-catalyzed carbonylative reactions of aryl iodides by using molybdenum hexacarbonyl as a convenient solid carbonyl source and avoiding a direct handling of gaseous carbon monoxide. Real-time monitoring of the mechanochemical reaction by in situ pressure sensing revealed that CO is rapidly transferred from Mo(CO)6 to the active catalytic system without significant release of molecular carbon monoxide.
- van Bonn, Pit,Bolm, Carsten,Hernández, José G.
-
p. 2576 - 2580
(2020/02/20)
-
- HMF and furfural: Promising platform molecules in rhodium-catalyzed carbonylation reactions for the synthesis of furfuryl esters and tertiary amides
-
A biomass involved rhodium-catalyzed carbonylative synthesis of furfuryl esters and tertiary amides has been developed. 5-Hydroxymethylfurfural (HMF) was used as both substrate and CO surrogate for the first time in a carbonylation reaction, and both alkyl and aryl iodides were tolerated well to afford the desired furfuryl esters in moderate to good yields. In addition, furfural was also utilized as a CO source for the synthesis of tertiary amides. A variety of tertiary amides were obtained in moderate to excellent yields with good functional groups compatibility. Notably, tertiary amines were used as the amine source through a C[sbnd]N bond cleavage pathway in the absence of additional oxidant.
- Qi, Xinxin,Zhou, Rong,Ai, Han-Jun,Wu, Xiao-Feng
-
p. 215 - 221
(2019/11/25)
-
- Cobalt-catalyzed aminocarbonylation of (hetero)aryl halides promoted by visible light
-
The catalytic aminocarbonylation of (hetero)aryl halides is widely applied in the synthesis of amides but relies heavily on the use of precious metal catalysis. Herein, we report an aminocarbonylation of (hetero)aryl halides using a simple cobalt catalyst under visible light irradiation. The reaction extends to the use of (hetero)aryl chlorides and is successful with a broad range of amine nucleophiles. Mechanistic investigations are consistent with a reaction proceeding via intermolecular charge transfer involving a donor-acceptor complex of the substrate and cobaltate catalyst.
- Alexanian, Erik J.,Veatch, Alexander M.
-
p. 7210 - 7213
(2020/07/23)
-
- Tert -Butyl nitrite promoted transamidation of secondary amides under metal and catalyst free conditions
-
A mild and efficient method is demonstrated for the transamidation of secondary amides with various amines including primary, secondary, cyclic and acyclic amines in the presence of tert-butyl nitrite. The reaction proceeds through the N-nitrosamide intermediate and provides the transamidation products in good to excellent yields at room temperature. Moreover, the developed methodology does not require any catalyst or additives.
- Sureshbabu, Popuri,Azeez, Sadaf,Chaudhary, Priyanka,Kandasamy, Jeyakumar
-
supporting information
p. 845 - 850
(2019/01/30)
-
- Nickel-catalyzed reductive defunctionalization of esters in the absence of an external reductant: Activation of C-O bonds
-
The nickel-catalyzed reductive cleavage of esters in the absence of an external reductant, which involves the cleavage of an inert acyl C-O bond in O-Alkyl esters is reported. Various groups, such as N-containing heterocycles, esters, amides, and even arene rings can function as a directing group.
- Iyori, Yasuaki,Takahashi, Kenjiro,Yamazaki, Ken,Ano, Yusuke,Chatani, Naoto
-
supporting information
p. 13610 - 13613
(2019/11/14)
-
- Clickable coupling of carboxylic acids and amines at room temperature mediated by SO2F2: A significant breakthrough for the construction of amides and peptide linkages
-
The construction of amide bonds and peptide linkages is one of the most fundamental transformations in all life processes and organic synthesis. The synthesis of structurally ubiquitous amide motifs is essential in the assembly of numerous important molecules such as peptides, proteins, alkaloids, pharmaceutical agents, polymers, ligands and agrochemicals. A method of SO2F2-mediated direct clickable coupling of carboxylic acids with amines was developed for the synthesis of a broad scope of amides in a simple, mild, highly efficient, robust and practical manner (>110 examples, >90% yields in most cases). The direct click reactions of acids and amines on a gram scale are also demonstrated using an extremely easy work-up and purification process of washing with 1 M aqueous HCl to provide the desired amides in greater than 99% purity and excellent yields.
- Wang, Shi-Meng,Zhao, Chuang,Zhang, Xu,Qin, Hua-Li
-
p. 4087 - 4101
(2019/04/30)
-
- Alternative formation of amides and β-enaminones from aroyl chlorides using the TiCl4-trialkylamine reagent system
-
The TiCl4/NR3 reagent system has been successfully employed for the synthesis of amides and β-enaminones. The reaction of variously substituted benzoyl chlorides with the TiCl4/NR3 reagent system, by using two different experimental procedures (Method A and Method B), afforded alternatively the corresponding amides and β-enaminones as unique or major products. The two developed protocols were investigated with a series of tertiary amines. The reactions, modulated by the presence of TiCl4, provided the corresponding amides or β-enaminones with satisfactory yields. This paper reports a new method for carbon-carbon bond formation via the reaction of aroyl chlorides with the TiCl4/NR3 reagent system.
- Leggio, Antonella,Comandè, Alessandra,Belsito, Emilia Lucia,Greco, Marianna,Lo Feudo, Lucia,Liguori, Angelo
-
p. 5677 - 5683
(2018/08/17)
-
- Versatile Heterogeneous Palladium Catalysts for Diverse Carbonylation Reactions under Atmospheric Carbon Monoxide Pressure
-
Herein, we report a versatile carbonylation protocol using heterogeneous Pd0 nanoparticles supported on the metal–organic frameworks (MOFs) MIL-88B-NH2 (Fe/Cr). The synthesis of a vast array of carbonyls, which includes amides, esters, carboxylic acids, and α-ketoamides, was achieved through mono- and dicarbonylation reactions. The selectivity could be controlled simply by tuning the reaction conditions. Superior activity and selectivity were recorded in some cases compared to that achieved with commercial Pd/C. However, the utility of an elaborate catalyst support is questionable and important reactivity and recyclability issues are discussed.
- Vico Solano, Marta,González Miera, Greco,Pascanu, Vlad,Inge, A. Ken,Martín-Matute, Belén
-
p. 1089 - 1095
(2018/02/06)
-
- Sunlight assisted direct amide formation: Via a charge-transfer complex
-
We report on the use of charge-transfer complexes between amines and carbon tetrachloride, as a novel way to activate the amine for photochemical reactions. This principle is demonstrated in a mild, transition metal free, visible light assisted, dealkylative amide formation from feedstock carboxylic acids and amines. The low absorption coefficient of the complex allows deep light penetration and thus scale up to a gram scale.
- Cohen, Irit,Mishra, Abhaya K.,Parvari, Galit,Edrei, Rachel,Dantus, Mauricio,Eichen, Yoav,Szpilman, Alex M.
-
supporting information
p. 10128 - 10131
(2017/09/23)
-
- Sulfur–Fluoride Exchange (SuFEx)-Mediated Synthesis of Sterically Hindered and Electron-Deficient Secondary and Tertiary Amides via Acyl Fluoride Intermediates
-
Amide bond formation is one of the most executed reactions in chemistry and biology. This is largely due to the ubiquity of the amide functional group in biological molecules, natural products and pharmaceutically important drugs. We report here the development of “SuFExAmide”: a new sulfur–fluoride exchange (SuFEx) click chemistry based protocol for the efficient amidation of carboxylic acids via acyl fluoride intermediates. We have developed benzene-1,3-disulfonyl fluoride as a cost effective, powerful and versatile coupling agent, which delivers challenging secondary and tertiary amides in excellent yields from sterically hindered and electron-deficient amines. The straightforward method offers significant benefits over existing protocols in terms of substrate scope, efficiency and ease of operation and is demonstrated by the synthesis of 44 amides, including GNF6702, an antiprotozoal drug candidate. In the majority of cases, the amide products are obtained in high yield without the need for excess reagents or chromatographic purification.
- Smedley, Christopher J.,Barrow, Andrew S.,Spiteri, Christian,Giel, Marie-Claire,Sharma, Pallavi,Moses, John E.
-
p. 9990 - 9995
(2017/08/01)
-
- Palladium-Catalyzed Aminocarbonylation of Aryl Halides with 2,4,6-Trichloro-1,3,5-triazine/Formamide Mixed Reagent
-
In this work, the mixture of formamide and 2,4,6-trichloro-1,3,5-triazine (cyanuric chloride or TCT) is introduced as a new amidating agent in Pd-catalyzed aminocarbonylation of aryl halides. In the presence of a catalytic amount of palladium and TCT/formamide reagent, a range of aryl halides (X = Cl, Br, I) were converted into amides efficiently in N,N-dimethylformamide at 120 °C. The 2,4,6-trichloro-1,3,5-triazine/formamide mixed reagent was found to be an efficient amidating agent in Pd-catalyzed aminocarbonylation of aryl halides. In the presence of this reagent and a catalytic amount of Pd, a range of amides were synthesized by using aryl halides.
- Iranpoor, Nasser,Panahi, Farhad,Roozbin, Fatemeh,Erfan, Soodabeh,Rahimi, Sajjad
-
supporting information
p. 1781 - 1787
(2016/04/05)
-
- Pd/C-catalyzed aminocarbonylation of aryl iodides via oxidative C-N bond activation of tertiary amines to tertiary amides
-
This work reports oxidative N-dealkylation/carbonylation of tertiary amines to tertiary amides by using molecular oxygen as a sole oxidant using a Pd/C catalyst. This protocol is free from ligands, additives, bases, and cocatalysts. Different tertiary amines as well as aryl iodides have been examined for this transformation, providing desired products in good to excellent yield.
- Mane, Rajendra S.,Bhanage, Bhalchandra M.
-
p. 1223 - 1228
(2016/02/18)
-
- Palladium supported on triphenylphosphine-functionalized porous organic polymer: An efficient heterogeneous catalyst for aminocarbonylation
-
An efficient route for the catalytic synthesis of aryl amides via the aminocarbonylation of aryl iodides with amines is described using palladium supported on triphenylphosphine-functionalized porous organic polymer (Pd@KAPs(Ph-PPh3)) as the catalyst. Under low carbon monoxide pressure, the catalyst exhibited remarkable activity, and only 0.5 mol% palladium loading was required to achieve moderate to excellent yields (70-97 %) of aryl amides. The catalyst can be easily separated by a simple filtration process and recycled up to seven times with only minor loss of activity. The salient features of this protocol are the simplicity in handling of catalyst, low CO pressure, good functional group tolerance, high catalytic activity, negligible palladium leaching and effective catalyst recyclability.
- Lei, Yizhu,Zhang, Xuefeng,Gu, Yanlong,Hu, Jianglin,Li, Guangxing,Shi, Kaiyi
-
-
- Covalent triazine framework-supported palladium as a ligand-free catalyst for the selective double carbonylation of aryl iodides under ambient pressure of CO
-
Carbonylation of aryl iodides with amines under atmospheric pressure of CO, catalyzed by Pd/CTFs (covalent triazine frameworks) without any specific additives, leads to the highly selective synthesis of α-ketoamides.
- Wang, Zhifang,Liu, Cuibo,Huang, Yi,Hu, Yuchen,Zhang, Bin
-
supporting information
p. 2960 - 2963
(2016/02/19)
-
- Directed Metalation-Suzuki-Miyaura Cross-Coupling Strategies: Regioselective Synthesis of Hydroxylated 1-Methyl-phenanthrenes
-
A general, efficient, and regioselective synthesis of a series of hydroxylated 1-methylphenanthrenes 9 by a combined directed ortho metalation (DoM)-Suzuki-Miyaura cross-coupling-directed remote metalation (DreM) sequence is reported. Diversity to this methodology was achieved by a regioselective DoM rather than DreM reaction, affording more highly substituted phenanthrols (Table 2). Application of the turbo-Grignard reagent (i-PrMgCl·LiCl) in the Ni-catalyzed Corriu-Kumada reaction gave efficient decarbamoylation (Tables 3and 4). Additional features are the TMS protecting group and halo-induced ipso-desilylation tactics applied to the regioselective synthesis of phenanthrenes (Scheme 2).
- J?rgensen, K?re B.,Rantanen, Toni,D?rfler, Thilo,Snieckus, Victor
-
p. 9410 - 9424
(2015/10/12)
-
- Palladium-catalyzed methoxylation of aromatic chlorides with borate salts
-
Herein we disclose a simple palladiumcatalyzed transformation for the methoxylation of aromatic chlorides with tetramethoxyborate salts. The procedure provides a new and efficient synthetic tool for the introduction of a methoxy group into aromatic systems. In addition, the reaction can be achieved using a wide range of aromatic and heteroaromatic chlorides, the cheapest class of halides.
- Tolnai, Gergely L.,Petho, Bálint,Králl, Péter,Nováka, Zoltán
-
supporting information
p. 125 - 129
(2014/03/21)
-
- WCl6/DMF as a new reagent system for the phosphine-free Pd(0)-catalyzed aminocarbonylation of aryl halides
-
WCl6 in dimethyl formamide (DMF) is introduced as a new reagent system for aminocarbonylation of aryl halides in the presence of PdCl2 as pre-catalyst without any phosphorous ligand. Aryl iodides, bromides as well as chlorides were efficiently converted to their corresponding N,N-dimethyl amides in good to high yields. In this protocol, WCl6/DMF is responsible for the generation of both Pd(0) catalyst as well as the formation of a Vilsmeier imminium type intermediate.
- Iranpoor, Nasser,Firouzabadi, Habib,Rizi, Zeinab Tavangar,Erfan, Soodabeh
-
p. 43178 - 43182
(2015/02/19)
-
- A novel Pd-catalyzed N-dealkylative carbonylation of tertiary amines for the preparation of amides
-
A novel and convenient protocol for the formation of amides via palladium-catalyzed N-dealkylative carbonylation of alkyl tertiary amines has been developed. In the presence of PdCl2(PhCN)2, CuO, PhCN and CO, a range of substituents on both aryl iodides and alkyl tertiary amines were compatible with the reaction to afford a series of N,N-disubstituted amides in moderate to excellent yields. This journal is
- Fang, Tao,Gao, Xu-Hong,Tang, Ri-Yuan,Zhang, Xing-Guo,Deng, Chen-Liang
-
supporting information
p. 14775 - 14777
(2014/12/11)
-
- Palladium-1,10-phenanthroline complex encaged in y zeolite: An efficient and highly recyclable heterogeneous catalyst for aminocarbonylation
-
A promising route for catalytic synthesis of amides by aminocarbonylation of aryl iodides with amines is described using a palladium-1,10-phenanthroline complex encaged in Y zeolite. Complete conversions for aryl iodides and good to excellent yields (71-97%) of various amides were obtained at low Pd loadings of 0.6 mol%. The turnover frequency (TOF) could be up to 139 h-1. A satisfactory yield was obtained even after the catalyst was reused 16 times and the total turnover number (TON) for the 16 cycles was up to 2250. As evidenced by atomic absorption spectrophotometry, UV-vis spectroscopy and X-ray photoelectron spectroscopy, the palladium complex could well nestle down in the supercages of the zeolite without leaching during the recycling process. The significantly enhanced recyclability could be attributed to the double-protection strategy provided by the ligand and the zeolite structure for Pd0 species generated in situ within supercages preventing the migration and leaching of palladium. The supported catalyst has the advantages of easy handing, good to excellent yields, and outstanding recycling capacity for aminocarbonylation reactions of aryl iodides.
- Mei, Hui,Hu, Jianglin,Xiao, Se,Lei, Yizhu,Li, Guangxing
-
-
- NHC-Pd complex-catalyzed double carbonylation of aryl iodides with secondary amines to α-keto amides
-
A series of palladium-NHC compounds were prepared and their catalytic activity in the double carbonylation of aryl iodides to synthesize α-keto amides were examined. Palladium complexes bearing mixed NHC-phosphine exhibited high efficiency for the double carbonylation reaction. The effects of different solvents, base, temperature, carbon monoxide (CO), pressure, various amine and aryl iodides were investigated. Both electron-rich and electron-deficient aryl iodides afforded the corresponding substituted α-keto amides in moderate to good yields. A possible mechanism was also proposed. Copyright
- Zheng, Shuzhan,Wang, Yan,Zhang, Chunyan,Liu, Jianhua,Xia, Chungu
-
-
- Synthesis of N,N -diethylbenzamides via a nonclassical mitsunobu reaction
-
The use of the Mitsunobu reaction for the synthesis of N,N- diethylbenzamides affords ortho-, meta-, and para-substituted benzamides containing both electron-donating and electron-withdrawing groups. While the preparation of numerous functional groups has
- Hoffman, J. Mason,Miller, Justin N.,Gardner, Margaret E.,Lepar, Danielle R.,Pongdee, Rongson
-
supporting information
p. 976 - 980
(2014/03/21)
-
- Highly selective palladium-catalysed aminocarbonylation of aryl iodides using a bulky diphosphine ligand
-
An efficient methodology for the synthesis of amides via palladium-catalysed aminocarbonylation of aryl iodides is reported using the bulky cis-1,2-bis[(di-tert-butylphosphino)methyl]cyclohexane ligand under atmospheric pressure of carbon monoxide. Excellent conversions (up to 99%) and chemoselectivities (up to 99%) were obtained for a range of aryl iodides and amine nucleophiles. The effect of the substituents on the substrate and nucleophiles on the catalytic performance was investigated. An NMR study was also carried out and key intermediates of the catalytic cycle were detected and characterised. Copyright
- De La Fuente, Veronica,Godard, Cyril,Claver, Carmen,Castillon, Sergio
-
experimental part
p. 1971 - 1979
(2012/09/22)
-
- Pd(ii)-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates under mild conditions
-
A novel Pd-catalyzed decarboxylative cross-coupling of oxamic acids with potassium phenyltrifluoroborates has been realized under mild reaction conditions. This method provides an efficient access to N-mono- or N,N-disubstituted benzamides and benzoates.
- Li, Mingzong,Wang, Cong,Fang, Ping,Ge, Haibo
-
supporting information; experimental part
p. 6587 - 6589
(2011/06/25)
-
- Aerobic oxidation of secondary benzylic alcohols and direct oxidative amidation of aryl aldehydes promoted by sodium hydride
-
We reported herein new reactivities and possible mechanistic implications of a simplest oxidant (NaH/air) uncovered on a broad range of useful transformations, including aerobic alcohol oxidations, allylic alcohol isomerizations and oxidations, cyclopropyl alcohol fragmentations, and direct aryl aldehyde oxidative amidations. These readily implementable transition-metal-free processes feature exceptional material accessibility, operational simplicity, and environmental compatibility, and add new dimensions to its synthetic utilities that are fairly robust yet had not previously been fully realized and systematically explored.
- Wang, Xinbo,Wang, David Zhigang
-
supporting information; experimental part
p. 3406 - 3411
(2011/06/17)
-
- Ketopyrroles useful as ligands in organic iridium compositions
-
The present invention provides novel ketopyrroles having structure XXIV wherein R2 is independently at each occurrence a deuterium atom, a halogen, a nitro group, an amino group, a C3-C40 aromatic radical, a C1-C50 aliphatic radical, or a C3-C40 cyclcoaliphatic radical; “a” is an integer from 0 to 3; and X1 and X2 are independently at each occurrence a bromine atom, a hydroxy group, or the group OR10, and wherein the group R10 is independently at each occurrence a deuterium atom, a halogen, a nitro group, an amino group, a C3-C40 aromatic radical, a C1-C50 aliphatic radical, or a C3-C40 cyclcoaliphatic radical. Ketopyrroles XXIV are useful ligands for the preparation of Type (1) and Type (2) organic iridium compositions. In one aspect, the present invention provides deuterated analogs of XXIV. Organic iridium compositions are useful in the preparation optoelectronic devices, such as OLED devices and photovoltaic devices exhibiting enhanced performance characteristics.
- -
-
Page/Page column 36
(2008/06/13)
-
- Rational design of inhibitors of VirA-VirG two-component signal transduction
-
VirA-VirG two-component system regulates the vir (virulence) operon in response to specific host factors (xenognosins) in the plant pathogen Agrobacterium tumefaciens. Using whole cell assays, stable inhibitors inspired by the labile natural benzoxazinone inhibitor HDMBOA are developed. It is found that aromatic aldehydes represent a minimal structural unit for activity. In particular, 3-hydroxy-4,6-dimethoxy-3H-isobenzofuran-1-one (HDI) was found to have the highest activity, making it the most potent developed inhibitor of virulence gene expression in Agrobacterium.
- Maresh, Justin,Zhang, Jin,Tzeng, Yih-Ling,Goodman, Nora A.,Lynn, David G.
-
p. 3281 - 3286
(2008/02/08)
-
- A mild and efficient reaction for conversion of carboxylic acids into acid bromides with ethyl tribromoacetate/triphenylphosphine under acid-free conditions
-
Acid bromides were prepared efficiently from carboxylic acids with readily available ethyl tribromoacetate and triphenylphosphine at room temperature under neutral conditions. The present process is applicable to the preparation of various acid bromides from aromatic and aliphatic carboxylic acids. Aromatic carboxylic acids were found to be more reactive than aliphatic carboxylic acids under reaction conditions.
- Kang, Dong Ho,Joo, Tae Young,Lee, Eun Hwa,Chaysripongkul, Skaydaw,Chavasiri, Warinthorn,Jang, Doo Ok
-
p. 5693 - 5696
(2007/10/03)
-
- An efficient conversion of nitriles to amides: Application in the synthesis of N,N-diethyl-m-toluamide (DEET)
-
Arylnitriles react with magnesium amides to produce carboxamides in excellent yield. The method was applied for the preparation of the insect repellent DEET.
- Bhattacharya, Apurba,Plata, Robert Erik,Villarreal, Victor,Muramulla, Savitha,Wu, Jiejun
-
p. 505 - 506
(2007/10/03)
-
- [Bis(2-methoxyethyl)amino]sulfur Trifluoride, the Deoxo-Fluor Reagent: Application toward One-Flask Transformations of Carboxylic Acids to Amides
-
The use of the Deoxo-Fluor reagent is a versatile method for acyl fluoride generation and subsequent one-flask amide coupling. It provides mild conditions and facile purification of the desired products in good to excellent yields. We have explored the utility of this reagent for the one-flask conversion of acids to amides and Weinreb amides and as a peptide-coupling reagent.
- White, Jonathan M.,Tunoori, Ashok Rao,Turunen, Brandon J.,Georg, Gunda I.
-
p. 2573 - 2576
(2007/10/03)
-
- Selenoxanthones via directed metalations in 2-arylselenobenzamide derivatives
-
The reaction of N, N-diethyl 4-(N′, N′-dimethylamino)-2-phenylselenobenzamide (7a), N, N-diethyl 4-methoxy-2-phenylselenobenzamide (7b), N, N-diethyl 4-(N′, N′-dimethylamino)-2-[(3-(N, N-dimethylamino)phenylseleno]-benzamide (7c), and N, N-diethyl 4-metho
- Brennan, Nancy K.,Donnelly, David J.,Detty, Michael R.
-
p. 3344 - 3347
(2007/10/03)
-
- Double carbonylation of aryl iodides with diethylamine catalyzed by dinuclear palladium complexes
-
Dinuclear palladium complexes bridged by a novel PNNP ligand, N,N ′-bis[(2-diphenylphosphino)phenylformamidinate (dpfam), were found to be very efficient and selective catalysts for the double carbonylation of iodobenzene with diethylamine using K3PO4 as base and 1,4-dioxane as solvent with a TON up to 105 and selectivity of 96%.
- Tsukada, Naofumi,Ohba, Yoichi,Inoue, Yoshio
-
p. 436 - 443
(2007/10/03)
-
- METHOD FOR STORING QUATERNARY AMMONIUM SALT
-
A method of improving the stability of a quaternary ammonium salt and a method of efficiently preparing the quaternary ammonium salt having improved stability.
- -
-
-
- Pd-benzothiazole carbene catalysed carbonylation of aryl halides in ionic liquids
-
The carbonylations of aryl halides with the Pd-carbene catalyst 1 were studied both in molecular solvents and in ionic liquids (ILs). Among the ILs, tetrabutylammonium bromide (TBAB) was found to give better results. Under these conditions the catalyst, when recovered and reused, did not show a significant decrease of activity. The role of TBAB on the catalyst stability is discussed.
- Calò, Vincenzo,Giannoccaro, Potenzo,Nacci, Angelo,Monopoli, Antonio
-
p. 152 - 157
(2007/10/03)
-
- Synthesis of S-thioacyl dithiophosphates, efficient and chemoselective thioacylating agents
-
Easily available acyl dithiophosphates are not stable and isomerise reversibly to O-thioacyl monothiophosphates, especially when subjected to heating. Much slower but probably irreversible isomerisation to S-thioacyl monothiophosphates occurs. Since equilibrium states are established and S-thioacyl (mono)thiophosphates form slowly, reaction mixtures contain generally both thioacylating and acylating agents, and consequently cannot be used for efficient thioacylation. On the other hand, treatment of a mixture of isomeric anhydrides with an excess of a dithiophosphoric acid leads to exclusive formation of S-thioacyl dithiophosphates. They appear to be excellent thioacylating agents: relatively stable, inert towards water and oxygen and therefore easy to handle. Reactions with nitrogen or sulfur nucleophiles proceed very rapidly under ambient conditions, yielding respective thioacyl derivatives. Isolation of the products is very simple. Due to the low reactivity of S-thioacyl dithiophosphates towards oxygen nucleophiles they can be used for direct thioacylation of multifunctional nucleophiles with unprotected hydroxy groups. Respective thioacyl derivatives cannot readily be obtained using other methods.
- Doszczak, Leszek,Rachon, Janusz
-
p. 1271 - 1279
(2007/10/03)
-
- Behavior of organic compounds confined in monoliths of sol-gel silica glass. Effects of guest-host hydrogen bonding on uptake, release, and isomerization of the guest compounds
-
Various proteins, catalysts, and other compounds can be encapsulated or diffused into porous sol-gel glasses, but little is known about their interactions with the glass matrix. We report unexpectedly large effects that hydrogen bonding between organic co
- Badjic,Kostic
-
p. 408 - 418
(2007/10/03)
-
- Cross-coupling reactions of carbamoyl chlorides and Grignard reagents: A new rapid synthesis of tertiary amides
-
Tributyl phosphine or nickel catalysts allow the cross-coupling reaction between N,N-dialkylcarbamoyl chlorides and alkyl or aryl Grignard reagents. This convenient and simple method affords tertiary amides with moderate to excellent yields in short reaction times. (C) 2000 Elsevier Science Ltd.
- Lemoucheux,Rouden,Lasne
-
p. 9997 - 10001
(2007/10/03)
-
- A convenient method for the synthesis and one-pot reaction of acyl chlorides using a scavenging resin
-
A simple, efficient and fast method for the preparation of acyl halides from fatty carboxylic acids using a solid phase scavenging approach is presented herein. The title compounds can then be isolated, used as a solution or react in one-pot to form esters and amides with good to excellent yields.
- Girard,Tranchant,Niore,Herscovici
-
p. 1577 - 1580
(2007/10/03)
-
- A direct and mild conversion of tertiary aryl amides to methyl esters using trimethyloxonium tetrafluoroborate: A very useful complement to directed metalation reactions
-
The scope and generality of a direct process for the conversion of tertiary amides directly to methyl esters has been investigated. The process involves a two-step, one pot procedure in which a tertiary amide is first treated with trimethyloxonium tetrafluoroborate to generate an imidate intermediate which is then hydrolyzed, generally by the addition of saturated aqueous sodium bicarbonate solution. Although this process fails for aliphatic amides, very good yields are realized for a variety of amides derived from aromatic carboxylic acids. Steric hindrance at the N-alkyl group is well tolerated; thus N,N-dimethyl, -diethyl, and -diisopropyl amides can all be utilized successfully. (C) 2000 Elsevier Science Ltd.
- Keck, Gary E,McLaws, Mark D,Wager, Travis T
-
p. 9875 - 9883
(2007/10/03)
-
- Synthesis of tricyclic aryl spiroacetals related to the papulacandins
-
A convenient synthesis of aryl spiroacetals related to the antifungal agents, the populacandins, is reported. The synthetic methodology involves the addition of ortho-lithiated diethylbenzamides to lactones followed by acid catalysed cyclization of the resultant keto-alcohols.
- Brimble, Margaret A.,Robinson, Stuart G.
-
p. 9553 - 9562
(2007/10/03)
-
- BeCl2 as a new highly selective reagent for dealkylation of aryl-methyl ethers
-
An efficient and simple method is introduced for the selective removal of methyl group from poly aryl-methyl ethers, in some important derivatives of benzophenones, xanthones, anthraquinones, aryl esters, benzamides and nitroanisoles with BeCl2.
- Sharghi, Hashem,Tamaddon, Fatemeh
-
p. 13623 - 13640
(2007/10/03)
-
- The Synthesis of Mycophenolic Acid from 2,4-Dihydroxybenzoic Acid
-
Mycophenolic acid (1) has been synthesized from 2,4-dihydroxybenzoic acid by regioselective introduction of the three required carbon substituents.A key transformation in this sequence is the introduction of the methyl substituent at position 5 by a rapid, uncatalyzed replacement of the bromide in 8 at low temperature by methyllithium.The scope and mechanism of this methylation reaction are examined.
- Patterson, John W.
-
p. 4542 - 4548
(2007/10/02)
-
- Acylpalladation of internal alkynes and palladium-catalyzed carbonylation of (Z)-β-iodoenones and related derivatives producing γ-lactones and γ-lactams
-
The reaction of either an internal alkyne-organic halide mixture or (Z)-β-iodoenones with CO in the presence of a Pd-phosphine catalyst, e.g., Cl2Pd(PPh3)2, can give one of the three discrete types of compounds as the major products depending on the substrate structure and the reaction conditions. Those substrates which are convertible to (Z)-γ-oxo-α,β-unsaturated acylpalladium derivatives lacking δ-H atoms are converted to the corresponding 2-butenolides (13) in the presence of water, which serves as a H donor. Carbon monoxide most likely is the source of two electrons. Either in the absence of water (or any other suitable H source) or in the presence of some factors disfavoring the butenolide formation, the same reaction gives the corresponding dimeric product (16). Even in cases where there is an α-H atom in the α-substitutent, 1,4-elimination products (11), reported to be the major products in a related Pd-catalyzed reaction of terminal alkyne-aryl iodide mixtures with CO, were not detected. In sharp contrast, those substrates which can give rise to (Z)-γ-oxo-α,β-unsaturated acylpalladium derivatives containing δ-H atoms give, under comparable reaction conditions, enol lactones (12), i.e., (Z)-3-alkylidene-2-butenolides, contaminated with only very minor amounts of 22 even in cases where an excess (4 equiv) of water was present. The required (Z)-β-iodoenones can be readily prepared in one pot via ZrCp2-promoted cyclization of alkynes with nitriles. The ready availability of the starting compounds and the high Z stereoselectivity make the overall sequence an attractive synthetic route to 12. The courses of the Pd-catalyzed carbonylation reactions of (Z)-β-iodo-α,β-unsaturated imines 23 closely parallel the reactions of enones and produce the corresponding lactams, i.e., 24 and 25.
- Copéret, Christophe,Sugihara, Takumichi,Wu, Guangzhong,Shimoyama, Izumi,Negishi, Ei-Ichi
-
p. 3422 - 3431
(2007/10/02)
-
- SACCHARIN DERIVATIVE PROTEOLYTIC ENZYME INHIBITORS
-
Compounds having the structural formula STR1 which inhibit the enzymatic activity of proteolytic enzymes, and processes for preparation thereof, method of use thereof in treatment of degenerative diseases and pharmaceutical compositions thereof are disclosed.
- -
-
-
- BISCARBAMOYL DISELENIDES AS NEW CARBAMOYLATING REAGENTS. LEWIS ACID PROMOTED CARBAMOYLATION OF AROMATIC COMPOUNDS
-
The reaction of biscarbamoyl diselenides with aromatic compounds in the presence of Lewis acids resulted in Friedel-Crafts type carbamoylation (Gatterman amide synthesis) to give corresponding aromatic amides in good yields.This methodology was successfully applied to aroylation and benzylation by use of dibenzoyl diselenide and dibenzyl diselenide, respectively.
- Fujiwara, Shin-Ichi,Ogawa, Akiya,Kambe, Nobuaki,Ryu, Ilhyong,Sonoda, Noboru
-
p. 6121 - 6124
(2007/10/02)
-
- Palladium-Catalysed Double Carbonylation of Aryl Halides To Give α-Keto Amides. Mechanistic Studies
-
Various aryl halides are catalytically converted into α-keto amides and amides on treatment with secondary amines and carbon monoxide.Palladium complexes containing tertiary phosphine ligands, particularly diphenylmethylphosphine and 1,4-bis(diphenylphosphino)butane, are most effective among other transition-metal complexes.Detailed examination of factors controlling the reaction rates and selectivity for α-keto amide formation revealed the following characteristics of the reactions. (a) Reactivity of phenyl halide decreases in the order PhI > PhBr >> PhCl. (b) Oxidative addition of phenyl bromide constitutes the rate-determining step in double carbonylation of phenyl bromide, whereas in the reaction of phenyl iodide the rate determinig step is associated with the reaction of a catalitically active palladium species with carbon monoxide. (c) Introduction of an electron-withdrawing substituent into the para position of phenyl halide enhances the reactivity but decreases the selectivity for α-keto amide. (d) Employment of amines of high basicity (pKb Et2NH > piperidine > hexamethyleneimine > Me2NH > pyrrolidine probably reflects the decrease in steric bulkiness of amines. (f) Although primary amines are in general not suitable for the double carbonylation, tert-butylamine can be used because of its inertness to the product α-keto amide.Reactivity of trans-PdPh(I)(PMePh2)2 and trans-Pd(COPh)I(PMePh2)2, supposed intermediates in the catalytic reaction of PhI, toward amines and CO was examined.The relative reactivity of six secondary amines with the benzoylpalladium complex increasing in the order Pr2NH Et2NH piperidine Me2NH hexamethyleneimine pyrrolidine was found to be inversely correlated with decreasing selectivity order for α-keto amide formation in the catalytic systems.On the basis of the experimental results, a mechanism consisting of two catalytic cycles to produce α-keto amides and amides has been proposed.
- Ozawa, Fumiyuki,Soyama, Hidehiko,Yanagihara, Hisayoshi,Aoyama, Issei,Takino, Hiroaki,et al.
-
p. 3235 - 3245
(2007/10/02)
-
- CATALYTIC DOUBLE CARBONYLATION OF ORGANOHALOGEN COMPOUNDS PROMOTED BY PALLADIUM COMPLEXES
-
Various organohalogen compounds can be catalytically converted into α-keto amides on reaction with carbon monoxide and amines.Tertiary phosphine-coordinated palladium compounds are particularly suitable as the double carbonylation catalyst.
- Ozawa, Fumiyuki,Soyama, Hidehiko,Yamamoto, Takakazu,Yamamoto, Akio
-
p. 3383 - 3386
(2007/10/02)
-
- Reaction of Diazonium Salts with Transition Metals. 6. Preparation of Mixed Acid Anhydrides from Arenediazonium Salts and Sodium Carboxylates under Palladium(0) Catalysis
-
The palladium(0)-catalyzed reaction of arenediazonium tetrafluoroborates with carbon monoxide and sodium carboxylates in acetonitrile at 25 deg C gave mixed acid anhydrides, ArCOOCOR (Ar = 3-Me-Ph, 4-Me-Ph, 2-MeO-Ph, 4-Br-Ph, 4-I-Ph, 3-NO2-Ph, 4-NO2-Ph, and Ph; R = H, Me, Et, t-Bu, and Ph) in good yields.Homoaromatic acid anhydrides, (ArCO)2O, were obtained by heating of ArCOOCOMe at 100-120 deg C under vacuum.ArCOOCO-t-Bu can be utilized to obtain the corresponding arenecarboxamides by the reaction with some amines.
- Kikukawa, Kiyoshi,Kono, Kiyoshi,Nagira, Kazuhiko,Wada, Fumio,Matsuda, Tsutomu
-
p. 4413 - 4416
(2007/10/02)
-