- Pd-Catalyzed Double-Decarbonylative Aryl Sulfide Synthesis through Aryl Exchange between Amides and Thioesters
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We report the palladium-catalyzed double-decarbonylative synthesis of aryl thioethers by an aryl exchange reaction between amides and thioesters. In this method, amides serve as aryl donors and thioesters are sulfide donors, enabling the synthesis of valuable aryl sulfides. The use of Pd/Xantphos without any additives has been identified as the catalytic system promoting the aryl exchange by C(O)-N/C(O)-S cleavages. The method is amenable to a wide variety of amides and sulfides.
- Bie, Fusheng,Cao, Han,Liu, Chengwei,Liu, Xuejing,Shi, Yijun,Szostak, Michal,Zhou, Tongliang
-
supporting information
p. 8098 - 8103
(2021/10/25)
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- A Fast and General Route to Ketones from Amides and Organolithium Compounds under Aerobic Conditions: Synthetic and Mechanistic Aspects
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We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over-addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale-up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre-activated amides, as recommended.
- Ghinato, Simone,Territo, Davide,Maranzana, Andrea,Capriati, Vito,Blangetti, Marco,Prandi, Cristina
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supporting information
p. 2868 - 2874
(2021/01/21)
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- Direct C2-arylation ofN-acyl pyrroles with aryl halides under palladium catalysis
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C2-arylation ofN-acyl pyrroles with aryl halides is developed for the first time using Pd(PPh3)4as a catalyst in combination with Ag2CO3under air, which allowed the application of a good compatibility catalytic system. This protocol provides a straightforward method for the preparation of valuable arylated pyrroles in moderate to good yields under the standard conditions with good substrate tolerance. Interestingly, whileN-benzoyl pyrroles reacted well, the use of substrates with a thiophene or furan ring indicated that the thiophene and furan rings are more reactive than pyrrole for the present catalytic system.
- Chen, Weiqiang,Li, Hui-Jing,Cheng, Yun-Fei,Wu, Yan-Chao
-
supporting information
p. 1555 - 1564
(2021/03/01)
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- Direct oxidative coupling of: N -acyl pyrroles with alkenes by ruthenium(ii)-catalyzed regioselective C2-alkenylation
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Ruthenium(ii)-catalyzed oxidative coupling by C2-alkenylation of N-acyl pyrroles with alkenes has been described. The acyl unit was found to be an effective chelating group for the activation of aryl C-H bonds ortho to the directing group. The alkenylation reaction of benzoyl pyrroles occurred regioselectively at the C2-position of the pyrrole ring, without touching the benzene ring. The reaction provides exclusively monosubstituted pyrroles under the optimized conditions. Disubstituted pyrroles could be obtained using higher loadings of the ruthenium(ii)-catalyst and the additives.
- Chen, Weiqiang,Li, Hui-Jing,Li, Qin-Ying,Wu, Yan-Chao
-
supporting information
p. 500 - 513
(2020/01/30)
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- Synthesis of N -Sulfonyl- and N -Acylpyrroles via a Ring-Closing Metathesis/Dehydrogenation Tandem Reaction
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N -Sulfonyl- and N -acylpyrroles were synthesized via olefin ring-closing metathesis of diallylamines and in situ oxidative aromatization in the presence of the ruthenium Grubbs catalyst and a suitable copper catalyst. In the presence of Cu(OTf) 2/s
- Chen, Weiqiang,Li, Hui-Jing,Liu, Ying,Nan, Xiang,Wu, Yan-Chao,Zhang, Yin-Lin
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p. 3651 - 3666
(2019/09/30)
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- Dinuclear manganese alkoxide complexes as catalysts for C-N bond cleavage of simple tertiary: N, N -dialkylamides to give esters
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Amide bonds are stable due to the resonance between the nitrogen lone pair and the carbonyl moiety, and therefore the chemical transformation of amides, especially tertiary amides, involving C-N bond fission is considered one of the most difficult organic reactions, unavoidably requiring harsh reaction conditions and strong acids or bases. We report the catalytic C-N bond cleavage of simple tertiary N,N-dialkylamides to give corresponding esters using a catalyst system (2 mol% based on Mn atoms) of a tetranuclear manganese alkoxide, [Mn(acac)(OEt)(EtOH)]4 (1c), combined with four equivalents of 4,7-bis(dimethylamino)-1,10-phenanthroline (L1: Me2N-Phen). Regarding the reaction mechanism, we isolated a dinuclear manganese complex, [Mn(acac)(OEt)(Phen)]2 (6c), which was revealed as the catalytically active species for the esterification of tertiary amides.
- Nagae, Haruki,Hirai, Takahiro,Kato, Daiki,Soma, Shusei,Akebi, Shin-Ya,Mashima, Kazushi
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p. 2860 - 2868
(2019/03/13)
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- Ni-Catalyzed cross-coupling reactions of N-acylpyrrole-type amides with organoboron reagents
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The catalytic conversion of amides to ketones is highly desirable yet challenging in organic synthesis. We herein report the first Ni/bis-NHC-catalyzed cross-coupling of N-acylpyrrole-type amides with arylboronic esters to obtain diarylketones. This method is facilitated by a new chelating bis-NHC ligand. The reaction tolerates diverse functional groups on both arylamide and arylboronic ester partners including sensitive ester and ketone groups.
- Huang, Pei-Qiang,Chen, Hang
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p. 12584 - 12587
(2017/11/30)
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- Reactivity of 7-Azanorbornenes in Bioorthogonal Inverse Electron-Demand Diels–Alder Reactions
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In the preparation of multicomponent compounds, the accumulation of components through sequential click reactions is an attractive strategy. In this work we examined the reactivity of various N-substituted 7-azanorbornenes in inverse electron-demand Diels–Alder (iEDDA) reactions with tetrazines to explore the potential of 7-azanorbornenes as clickable hub molecules. The iEDDA reaction of 7-azanorbornene is expected to proceed faster when the nitrogen atom at the 7-position is substituted with an electron-donating substituent. Contrary to this expectation, the electron-donating alkyl-bearing derivative reacted much more slowly than those bearing electron-withdrawing acyl groups. The results of DFT calculations indicate that the reaction rates correlate well with an increase in sp2 character of the 7-nitrogen atoms: The ease of conversion of the more stable exo conformer into the more reactive endo conformer may lower the activation energy of the first rate-determining hetero-Diels–Alder step. Indeed, the reaction rates of N-acylated 7-azanorbornenes, which have a more planar nitrogen atom, were found superior to those of other derivatives and comparable to those of norbornenes. Finally, we successfully labeled a tetrazine on a protein surface by fluorophore-conjugated 7-azanorbornene in the presence of other proteins.
- Karaki, Fumika,Ohgane, Kenji,Imai, Hirotaka,Itoh, Kennosuke,Fujii, Hideaki
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p. 3815 - 3829
(2017/07/22)
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- Suzuki-Miyaura Cross-Coupling of N-Acylpyrroles and Pyrazoles: Planar, Electronically Activated Amides in Catalytic N-C Cleavage
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The formation of C-C bonds from amides by catalytic activation of the amide bond has been thus far possible by steric distortion. Herein, we report the first example of a general Pd-catalyzed Suzuki-Miyaura cross-coupling of planar amides enabled by the combination of (i) electronic-activation of the amide nitrogen in N-acylpyrroles and pyrazoles and (ii) the use of a versatile Pd-NHC catalysis platform. The origin and selectivity of forming acylmetals, including the role of twist, are discussed.
- Meng, Guangrong,Szostak, Roman,Szostak, Michal
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p. 3596 - 3599
(2017/07/15)
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- An efficient and green method for regio- and chemo-selective Friedel-Crafts acylations using a deep eutectic solvent ([CholineCl][ZnCl2]3)
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[CholineCl][ZnCl2]3, a deep eutectic solvent between choline chloride and ZnCl2, has been used as a dual function catalyst and green solvent for the Friedel-Crafts acylation of aromatic compounds instead of using the moisture-sensitive Lewis acids and volatile organic solvents. The reactions are performed with high yields under microwave irradiation with short reaction times for the synthesis of ketones. Interestingly, indole derivatives are regioselectively acylated in the 3-position under mild conditions with high yields without NH protection. Three new ketone products are synthesized. [CholineCl][ZnCl2]3 is easily synthesized from choline chloride and zinc chloride at a low cost, with easy purification and environmentally benign compounds. [CholineCl][ZnCl2]3 can be reused up to five times without loss of catalytic activity, making it ideal in industrial processes.
- Tran, Phuong Hoang,Nguyen, Hai Truong,Hansen, Poul Erik,Le, Thach Ngoc
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p. 37031 - 37038
(2016/05/24)
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- A ring closing metathesis-manganese dioxide oxidation sequence for the synthesis of substituted pyrroles
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The combination of ring closing, or enyne metathesis with oxidation in order to prepare N-sulfonyl pyrroles is described. Reasonable to good yields were obtained for a variety of substituents and the procedure may also be conducted in one-pot. 2-Bromo N-sulfonyl adducts prepared in this manner were subjected to an intramolecular Heck-type cyclisation, forming cyclic sulfonamides.
- Keeley, Aaron,McCauley, Shane,Evans, Paul
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p. 2552 - 2559
(2016/04/26)
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- Samarium-mediated intramolecular cross-couplings of an α,β-unsaturated N-acylpyrrole
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The first example of an α,β-unsaturated N-acylpyrrole undergoing a SmI2-mediated cyclization is reported. In contrast to other unsaturated units, the intermediate samarium enolate readily engages in aldol-type reactions, necessitating careful control of the reaction conditions.
- Law, Katherine R.,McErlean, Christopher S.P.
-
supporting information
p. 3113 - 3116
(2016/07/06)
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- Synthesis of pyrrole derivatives from diallylamines by one-pot tandem ring-closing metathesis and metal-catalyzed oxidative dehydrogenation
-
A series of aryl-substituted pyrrole derivatives was synthesized from diallylamines through a ruthenium carbene catalyzed ring-closing metathesis reaction and in situ oxidative dehydrogenation reaction catalyzed by FeCl 3·6H2O or CuCl2·2H2O in the presence of O2. The reaction was mild, simple, and convenient. An oxygen atmosphere played a critical role in obtaining high conversion of substituted pyrroles in the proposed catalytic system.
- Chen, Weiqiang,Wang, Jianhui
-
supporting information
p. 1958 - 1963
(2013/05/08)
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- A practical preparation of highly versatile N-acylpyrroles from 2,4,4-trimethoxybutan-1-amine
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A novel method for the preparation of N-acylpyrrole is described. The method involves condensation of carboxylic acids with 2,4,4-trimethoxybutan-1- amine, followed by acid-mediated cyclization to form the pyrrole ring. The preparative procedure is highly
- Maehara, Tomoaki,Kanno, Rentaro,Yokoshima, Satoshi,Fukuyama, Tohru
-
supporting information; experimental part
p. 1946 - 1948
(2012/06/01)
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- Synthesis of acyl pyrroles via palladium-catalyzed carbonylative amination of aryl and alkenyl iodides
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A palladium-catalyzed synthesis of acyl pyrroles from aryl and alkenyl iodides is reported. This carbonylative amination requires only atmospheric (balloon) pressure of carbon monoxide and proceeds with Pd(PPh3) 4 and Pd-NHC catalyst
- Ho, Stephanie,Bondarenko, Ganna,Rosa, David,Dragisic, Bojan,Orellana, Arturo
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scheme or table
p. 2008 - 2012
(2012/04/17)
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- Unique chemoselective Clauson-Kass reaction of substituted aniline catalyzed by MgI2 etherate
-
Clauson-Kass reaction of various substituted aniline, primary aryl amide, and sufonyl amide with 2,5-dimethoxytetrahydrofuran was realized in the presence of 10 mol % of MgI2 etherate in a mild, efficient, and highly chemoselective manner. Iodide counterion and solvents (i.e., MeCN) played the critical roles for the unique reactivity of this catalytic system.
- Zhang, Xingxian,Shi, Junchen
-
experimental part
p. 898 - 903
(2011/03/19)
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- Mo(CO)6-mediated carbamoylation of aryl halides
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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)
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- METHOD FOR DEPROTECTING ARYL OR ALKYL SULFONAMIDES OF PRIMARY OR SECONDARY AMINES
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The invention relates to a method for removing an alkyl sulfonyl or aryl sulfonyl protecting group from a primary or secondary amine by contacting an alkyl sulfonamide or an aryl sulfonamide with a Stage 0 or Stage I alkali metal-silica gel material in the presence of a solid proton source under conditions sufficient to form the corresponding amine. The invention also relates to a method for removing an alkyl sulfonyl or aryl sulfonyl protecting group from a primary or secondary amine by a) reacting an alkyl sulfonamide or an aryl sulfonamide with a Stage 0 or Stage I alkali metal-silica gel material, and b) subsequently reacting the reaction product from step a) with an electrophile or a proton source. Preferred Stage 0 or Stage I alkali metal-silica gel materials include Na, K2Na, and Na2K.
- -
-
Page/Page column 8
(2009/12/24)
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- Iron-catalyzed inexpensive and practical synthesis of N-substituted pyrroles in water
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An operationally simple, practical, and economical protocol for iron(III) chloride catalyzed Paal-Knorr pyrrole synthesis in water in good to excellent yields has been developed. Several N-substituted pyrroles are readily prepared from the reaction of 2,5-dimethoxytetrahydrofuran and aryl/alkyl, sulfonyl and acyl amines under very mild reaction conditions. Georg Thieme Verlag Stuttgart.
- Azizi, Najmedin,Khajeh-Amiri, Alireza,Ghafuri, Hossein,Bolourtchian, Mohammad,Saidi, Mohammad Reza
-
experimental part
p. 2245 - 2248
(2009/12/03)
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- Alkali metals in silica gel (M-SG): A new reagent for desulfonation of amines
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(Chemical Equation Presented) A novel method for the desulfonation of secondary amines is described. Alkali metals absorbed into nanostructured silica (M-SG) were found to be useful solid-state reagents for the desuffonation of a range of N,N-disubstituted sulfonamides. M-SG reagents are room-temperature- stable free-flowing powders that retain the chemical reactivity of the parent metal, decreasing the danger and associated cost of using reactive metals.
- Nandi, Partha,Redko, Mikhail Y.,Petersen, Kathryn,Dye, James L.,Lefenfeld, Michael,Vogt, Paul F.,Jackson, James E.
-
supporting information; experimental part
p. 5441 - 5444
(2009/06/18)
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- Organic reactions in ionic liquids: A simple and highly regioselective N-substitution of pyrrole
-
In ionic liquids [Bmim][PF6] or [Bmim][BF4], pyrrole replaced the halogen atom of an alkyl halide to give the corresponding N-substituted pyrrole in excellent yield. Benzenesulfonyl chloride, p-methylbenzenesulfonyl chloride and benzoyl chloride reacted similarly with pyrroles to afford the N-substituted pyrroles in quantitative yield. Michael addition reaction of pyrrole with electrophilic olefins was completed in a highly regioselective manner to afford the N-alkylpyrroles.
- Le, Zhang-Gao,Chen, Zhen-Chu,Hu, Yi,Zheng, Qin-Guo
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p. 1951 - 1954
(2007/10/03)
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- A convenient synthesis of N-acylpyrroles from primary aromatic amides
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Synthesis of N-acylpyrroles in 45-85% isolated yield from primary aromatic amides and excess 2,5-dimethoxytetrahydrofuran in presence of one equivalent of thionyl chloride is reported. This method has several advantages including short reaction times, mild reaction conditions, and easy workup. The technique works particularly well for deactivated aromatic amides.
- Ekkati, Anil R.,Bates, Dallas K.
-
p. 1959 - 1961
(2007/10/03)
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- Remarkably stable tetrahedral intermediates: Carbinols from nucleophilic additions to N-acylpyrroles
-
Sufficiently stable intermediates formed in the reaction of N-acylpyrroles (1) with hydride and Grignard reagents can undergo further synthetic transformations and chromatographic purification to enable the generation of pyrrolecarbinols 2 in 76-95% yields [Eq. (1)].
- Evans, David A.,Borg, George,Scheidt, Karl A.
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p. 3188 - 3191
(2007/10/03)
-
- Synthesis and nuclear magnetic resonance spectroscopic studies of 1- arylpyrroles
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A series of m- and p-substituted 1-phenyl, 1-benzyl, 1-benzoyl, and 1- (2-phenylethyl)pyrroles was prepared and their 1H and 13C nmr spectroscopic characteristics were examined. In general, good correlations were observed between the chemical shift values of the β-H and the β-C of pyrroles [except 1-(2-phenylethyl)pyrroles] and the Hammettt σ. The observation may be explained in terms of the electronic effects of the substituents which are transmitted through bonds and through space by interaction of the p orbitals between β-Cs of the pyrrole ring and m- and p- Cs of the phenyl ring. Substituent constants of 1-pyrrolyl, 1-pyrrolylmethyl, and 1-pyrroloyl groups for the 1H and 13C chemical shifts of phenyl ring are also presented.
- Lee, Chang Kiu,Jun, Jung Ho,Yu, Ji Sook
-
-
- 1-(2,5-dichlorophenyl)-2,2-bis(methylsulfanyl)vinyl esters as highly efficient chemoselective acylating reagents
-
1-(2,5-Dichlorophenyl)-2,2-bis(methylsulfanyl)vinyl esters 4f-k were prepared in yields usually greater than 90%, by reacting acyl chlorides with 1-(2,5-dichlorophenyl)-2,2-bis(methylsulfanyl)ethanone enolate. These esters were demonstrated to be excellent chemoselective reagents for the acylation of amines, alcohols, thiols, pyrrole and indole. From all the acylation reactions the dimethyl α-oxo dithioacetal 2d, recyclable for the preparation of esters 4f-k, could be recovered in 90-100% yield.
- Degani,Dughera,Fochi,Serra
-
p. 1200 - 1208
(2007/10/03)
-
- A new method to N-arylmethylenepyrroles from N-acylpyrroles
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An efficient general method for the preparation of N-arylmethylenepyrroles based on the reduction of N-acylpyrroles is reported. The reduction procedure described is sufficiently mild to make it applicable to a variety of sensitive acyl and heterocyclic acyl compounds where reduction results in cleavage of the C-N bond. The method can also be used in the preparation of pyrrole derivatives containing base sensitive protecting groups.
- D'Silva, Claudius,Iqbal, Rifat
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p. 457 - 458
(2007/10/03)
-
- A facile synthesis of N-substituted pyrroles
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Phosphorous pentoxide is the catalyst of choice for the facile conversion of primary amines, aromatic amines, sulfonamides and primary amides into the corresponding N-substituted pyrroles from 2,5-dimethoxytetrahydrofuran.
- Fang,Leysen,Ottenheijm
-
p. 1857 - 1861
(2007/10/02)
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- Gas-phase heteroaromatic substitution. 11. Electron transfer mechanism in the gas-phase acylation of simple five-membered heteroarenes
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The results of a study of the gas-phase reactions of unsaturated carbocations, such as the CH3CO+ ion from γ-radiolysis of CH3F/CO mixtures, and the C6H4TCO+ ion from the β-decay of 1,4-ditritiobenzene in the presence of CO, with pyrrole, N-methylpyrrole, furan, and thiophene, are reported.In all systems investigated, acylated heteroarenes represent the predominant reaction products, accompanied by the methylated derivatives in the CH3F/CO radiolytic mixtures, and by the phenylated ones in the 1,4-ditritiobenzene/CO decay samples.All substrates investigated are found to undergo predominat α substitution by both acetyl (88.6-98.4percent (pyrrole); 90.8-98.7percent (N-methylpyrrole); 97.2-98.9percent (furan); 94.9-98.6percent (thiophene)) and benzoyl cations (92.6-96.5percent (pyrrole)) under all conditions.The predominant formation of the α-acylated pyrroles from both reactants (>88percent), whose relative yields appear unaffected within the temperature interval from 303 to 383 K, indicates, in agreement with ancillary FT-ICR mass spectrometric evidence, that gas-phase acylation reactions toward simple five-membered heteroarenes proceed via a two-step substitution mechanism, involving a quasi-resonant single-electron transfer (SET) step followed by recombination of the ensuing radical - radical ion pair.By virtue of this entropy-favored mechanism, gaseous electrophiles with relatively high SCF STO-3G calculated LUMO energies such CH3CO+ and C6H4TCO+ are effectively oriented toward the "soft" Cα sites of the selected heteroarenes, at variance with Klopman's Charge and Frontier Orbital Control predictions.The behavior of gaseous acylating reactants toward simple heteroarenes is discussed and compared with that of other gaseous electrophiles, whose reactivity appears instead in qualitative agreement with Klopman's model.
- Filippi, Antonello,Occhiucci, Giorgio,Sparapani, Cinzia
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p. 740 - 748
(2007/10/02)
-
- SYNTHESE DE PYRROLES ET D'OXAZOLES PAR PYROLYSE DE N-(HYDROXY-2' ETHYL) AMINO-3 PROPENOATE
-
The gas phas pyrolysis of various N-(2'-hydroxyethyl)-3-amino propenoates 1-6 and N-(2'-hydroxy-2'-phenyl ethyl)-3-amino propanoate 7-9 at 390 deg C-420 deg C leads respectively to formylpyrroles 11-16 and benzoylpyrroles 17-19 and, in some cases, to substituted oxazoles 36-39.The results are best explained by the intermediate formation of a dicarbonyl derivative followed either by an intramolecular thermal crotonisation or a six ? electrocyclization of an azomethine ylide.
- Pale-Grosdemange, Catherine,Chuche, Josselin
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p. 3397 - 3414
(2007/10/02)
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- Reactions at high pressure. Part 15. Rates, activation parameters, and a volume profile for retro-Diels-Alder reactions in the pyrrole series
-
Thermal decomposition of N-acylpyrrole adducts of N-phenylmaleimide by a ?2s + ?2s = ?2s> route occurs at temperature below 70 deg C.Rates and activation parameters for the termolyses of endo- and exo-10-benzoyl-4-phenyl-4,10-diazatricyclo2,6>dec-8-ene-3,5-dione (6) and (7), exo-10-acetyl-4-phenyl-4,10-diazatricyclo2,6>dec-8-ene-3,5-dione (8), and endo-4-phenyl-4-aza-10-oxatricyclodec-8-ene-3,5-dione (9) have been measured at various temperatures and pressures and in various solvents.It is confirmed that the volume of activation for thermolysis of (6) is negative, consistent with a transition state more compact than either reagents or products and not accountable for in terms of dipolar character.
- George, Adrian V.,Isaacs, Neil S.
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p. 1845 - 1848
(2007/10/02)
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- High-pressure Synthesis, Structures, and Conformational Properties of Some Derivatives of 7-Azabicycloheptane. X-Ray Determination of endo-10-Benzoyl-4-phenyl-4,10-diazatricyclo2,6>dec-8-ene-3,5-dione and exo-10-Acetyl-4-phenyl-4,10-diazatricyclo2,6>decane-....
-
The syntheses, using pressures up to 1.4 GPa, and the properties of Diels-Alder adducts of some N-acylated pyrroles are described.Both exo and endo adducts may be obtained and purified and are, in general, unstable with respect to the retro reaction.Progress towards a general synthesis of the 7-azabicycloheptane system is described.Structures of two of the adducts, those between N-phenylmaleimide (2b) and N-benzoylpyrrole (1a) and the dihydro adduct of (2b) with N-acetylpyrrole (1b), have been determined by X-ray crystallographic analysis.Examination of these structures by means of 1H n.m.r. temperature-dependent spectra and nuclear Overhauser effect differences confirm that conformational isomerism is due to restricted rotation about the amide C-N bond, the energy barrier, 70 kJ mol-1, being similar to that in acyclic amides.
- Drew, Michael G. B.,George, Adrian V.,Isaacs, Neil S.,Rzepa, Henry S.
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p. 1277 - 1284
(2007/10/02)
-
- CONVERSION OF PRIMARY AMIDES INTO ACTIVE ACYLATING AGENTS VIA ACYLPYRROLES.
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Several primary amides were converted to N-acylpyrroles on reaction with 1,4-dichloro-1,4-dimethoxybutane (1) and Amberlyst A-21 resin.The acylpyrroles act as active acylating agents.
- Lee, S.D.,Brook, Michael A.,Chan, T.H.
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p. 1569 - 1572
(2007/10/02)
-