- Synthesis of 2-Monosubstituted Pyrroles by Intramolecular Addition of Amines via Reductive Amination with Dibutyliodotin Hydride Complex (Bu 2SnIH-HMPA)
-
Various 2-monosubstituted pyrroles were prepared in a one-pot procedure via the reductive amination of formyl groups of multifunctional substrates 1 by using Bu2SnIH-HMPA system.
- Shibata, Ikuya,Kato, Hirofumi,Kanazawa, Nobuaki,Yasuda, Makoto,Baba, Akio
-
-
Read Online
- Copper-catalyzed pyrrole synthesis from 3,6-dihydro-1,2-oxazines
-
Highly-functionalized pyrroles could be effectively synthesized from 3,6-dihydro-1,2-oxazines using a heterogeneous copper on carbon (Cu/C) under neat heating conditions. Furthermore, the in situ formation of 3,6-dihydro-1,2-oxazines via the hetero Diels-Alder reaction between nitroso dienophiles and 1,3-dienes and the following Cu/C-catalyzed pyrrole synthesis also provided the corresponding pyrrole derivatives in a one-pot manner.
- Yasukawa, Naoki,Kuwata, Marina,Imai, Takuya,Monguchi, Yasunari,Sajiki, Hironao,Sawama, Yoshinari
-
supporting information
p. 4409 - 4413
(2018/10/17)
-
- Regioisomeric and Substituent Effects upon the Outcome of the Reaction of 1-Borodienes with Nitrosoarene Compounds
-
A study of the reactivity of 1-borodienes with nitrosoarene compounds has been carried out showing an outcome that differs according to the hybridization state of the boron moiety. Using an sp2 boron substituent, a one-pot hetero-Diels-Alder/ring contraction cascade occurred to afford N-arylpyrroles with low to good yields depending on the electronic properties of the substituents on the borodiene, whereas an sp3 boron substituent led to the formation of stable boro-oxazines with high regioselectivity in most of the cases, in moderate to good yields. 1H and 11B NMR studies on two boro-oxazine regioisomers showed that selective deprotection can be performed. Formation of either the pyrrole or the furan derivative is pH- and regioisomer-structure-dependent. The results obtained, together with previous B3LYP calculations, support mechanistic proposals which suggest that pyrrole, or furan, formation proceeds via oxazine formation, followed by a boryl rearrangement and an intramolecular addition-elimination sequence.
- Eberlin, Ludovic,Carboni, Bertrand,Whiting, Andrew
-
p. 6574 - 6583
(2015/10/06)
-
- Synthesis of polysubstituted pyrroles via Pd-catalyzed oxidative alkene C-H bond arylation and amination
-
A novel Pd(II)-catalyzed oxidative approach to construct polysubstituted pyrroles from N-homoallylicamines and arylboronic acids was developed. This transformation is supposed to proceed through cascade formation of C-C and C-N bonds via oxidative arylation of unactive alkenes, followed by intramolecular aza-Wacker cyclization.
- Zheng, Jia,Huang, Liangbin,Huang, Chuyu,Wu, Wanqing,Jiang, Huanfeng
-
p. 1235 - 1242
(2015/01/30)
-
- β-selective C-H arylation of pyrroles leading to concise syntheses of lamellarins C and I
-
The first general β-selective C-H arylation of pyrroles has been developed by using a rhodium catalyst. This C-H arylation reaction, which is retrosynthetically straightforward but results in unusual regioselectivity, could result in de novo syntheses of
- Ueda, Kirika,Amaike, Kazuma,Maceiczyk, Richard M.,Itami, Kenichiro,Yamaguchi, Junichiro
-
p. 13226 - 13232
(2015/03/30)
-
- Base-mediated intermolecular sp2 C-H bond arylation via benzyne intermediates
-
A transition-metal-free method for arylation of heterocycle and arene carbon-hydrogen bonds by aryl chlorides and fluorides has been developed. The reactions proceed via aryne intermediates and are highly regioselective with respect to the C-H bond coupling component.
- Truong, Thanh,Daugulis, Olafs
-
supporting information; experimental part
p. 4243 - 4245
(2011/06/21)
-
- Palladium-catalyzed indole, pyrrole, and furan arylation by aryl chlorides
-
The palladium-catalyzed direct arylation of indoles, pyrroles, and furans by aryl chlorides has been demonstrated. The method employs a palladium acetate catalyst, 2-(dicyclohexylphosphino)-biphenyl ligand, and an inorganic base. Electron-rich and electron-poor aryl chlorides as well as chloropyridine coupling partners can be used, and arylated heterocycles are obtained in moderate to good yields. Optimization of base, ligand, and solvent is required for achieving best results.
- Nadres, Enrico T.,Lazareva, Anna,Daugulis, Olafs
-
experimental part
p. 471 - 483
(2011/04/15)
-
- Palladium-catalyzed decarboxylative cross-coupling reaction between heteroaromatic Carboxylic acids and Aryl halides
-
"Chemical Equation Presented" A full overview of the decarboxylative cross-coupling reaction between heteroaromatic carboxylic acids and aryl halides is described. This transformation employs palladium catalysts with short reaction times providing facile synthesis of aryl-substituted heteroaromatics. The effect of each reaction parameter including solvent, base, and additive employed as well as the full substrate scope of this transformation are reported. Mechanistic evidence is also disclosed that sheds light on possible reaction pathways.
- Bilodeau, Francois,Brochu, Marie-Christine,Guimond, Nicolas,Thesen, Kris H.,Forgione, Pat
-
experimental part
p. 1550 - 1560
(2010/06/12)
-
- One-pot synthesis of heterocyclic compounds initiated by chemoselective addition to β-acyl substituted unsaturated aldehydes with nucleophilic tin complexes
-
β-Acyl substituted unsaturated aldehydes 1 were revealed to be good precursors for the synthesis of various heterocyclic compounds by the combination with tin nucleophiles. Various 2-monosubstituted pyrroles were prepared in an one-pot procedure via the reductive amination of formyl groups of 1 by using Bu2SnIH-HMPA complex. One-pot synthesis of heterocycles was carried out initiated by chemoselective reduction of 1 with Bu3SnH-HMPA complex and the subsequent reaction with heterocumulenes. Furthermore, the one-pot synthesis of nitrogen heterocyclic compounds accompanying chemo-, regio- and diastereoselective carbon-carbon bond formation in side chain moieties was effectively accomplished initiated by the regio- and diastereoselective allylation of the formyl group of 1 with allylic tin species.
- Shibata, Ikuya,Kato, Hirofumi,Yasuda, Makoto,Baba, Akio
-
p. 604 - 619
(2008/02/06)
-
- Synthesis of N-substituted 2-arylpyrroles by the reaction of (η2-imine)titanium complexes with 3,3-diethoxypropyne
-
(η2-Imine)Ti(O-i-Pr)2 complexes generated from arylaldehyde imines and a divalent titanium reagent, Ti(O-i-Pr)4/2i-PrMgCl, reacted with 3,3-diethoxypropyne to afford 2-arylpyrroles.
- Ohkubo, Mutsumi,Hayashi, Daisuke,Oikawa, Daisuke,Fukuhara, Kouki,Okamoto, Sentaro,Sato, Fumie
-
p. 6209 - 6212
(2007/10/03)
-
- Preparation of 1,2-diaryl(heteroaryl)pyrroles and -3-methylpyrroles from N-allylbenzotriazole
-
Numerous 1,2-diaryl(heteroaryl)pyrroles and -3-methylpyrroles were prepared in a two-step procedure from N-allylbenzotriazoles via intramolecular oxidative cyclization in the presence of Pd(II) catalyst.
- Katritzky,Zhang,Yao,Denisko
-
p. 8074 - 8076
(2007/10/03)
-
- Sulfur-Containing Heterocycles Derived by Reaction of ω-Keto Amides with Lawesson's Reagent
-
The reaction of ω-keto amides with Lawesson's reagent (LR: 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane 2,4-disulfide) is described. Treatment of 3-keto amides (2-acylacetamides) 1 with LR gave the corresponding 3-keto thioamides 2, along with 1,2-dithiole-3-thiones 3. Treatment of 4-keto amides, 3-acyl propionamides 5, with LR yielded five-membered heterocycles, pyrroles 6 and/or 2-aminothiophenes 7. 5-Keto amides, 3-benzoyl butyramides 8, reacted with LR to give dihydrothiopyran-2-thione 9 as the sole product, but in low yield. 2-Acylbenzamides 10 also reacted with LR to afford 3-mercaptoisoindolin-2-ones 11 or dihydroisobenzothiophene-1-thiones 12.
- Nishio, Takehiko
-
p. 1207 - 1214
(2007/10/03)
-
- The origins of the benzotriazole project, its versatility illustrated by a new --C = CHCH+OEt synthon, and novel syntheses of α,β-unsaturated aldehydes and ketones, furans, pyrroles and allyl ethers
-
A historical introduction describes the discovery and progress of benzotriazole synthetic methodology. 3-(Benzotriazol-1-yl)-1-ethoxyprop-1-ene (6), readily prepared from 3-(benzotriazol-1-yl)-3-ethoxyprop-1-ene (4) via zinc bromide promoted allylic rearrangement, undergoes lithiation and regiospecific single or double 3-alkylation to give products which undergo (i) hydrolysis to afford α,β-unsaturated aldehydes, (ii) silica gel promoted reverse allylic rearrangement of the benzotriazolyl group, followed by further alkylation and subsequent hydrolysis to furnish α,β-unsaturated ketones, (iii) intramolecular cyclizations to construct pyrroles and furans, and (iv) intermolecular nucleophilic substitution with Grignard reagents to provide allyl ethers.
- Katritzky,Wu,Xie,Rachwal,Rachwal,Jiang,Zhang,Lang
-
p. 1315 - 1323
(2007/10/02)
-
- A new convenient method to obtain pyrroles from tertiary N-allylthioamides
-
1,2-Disubstituted pyrroles 1 were synthesized from available thioamides 4. Thioamides were initially treated with either alkylating agents or Lewis acids to give salts 5 or complexes 12 which were subsequently reacted with base to yield pyrroles 1.
- Magedov, Igor V.,Kornienko, Alexander V.,Zotova, Tatyana O.,Drozd, Victor N.
-
p. 4619 - 4622
(2007/10/02)
-
- Electrochemical Cyclization of 1-Phenyl-2(-1'-chlorophenyl)-substituted Five-membered Nitrogen Heterocycles. Application to the Synthesis of Phenanthridines
-
Pyrrolophenanthridine (compound 4), 3-phenylimidazophenanthridine 8, tetrazolophenanthridine 11 and benzotetrazolophenanthridine 12 have been prepared using an electrochemical cyclizatin procedure.Treatment of the imidazophenanthridine with singlet oxygen yields a phenanthridone by degradation of the heterocyclic system.Lithium aluminium hydride reduction of the tetrazolophenanthridines yields the phenanthridine.
- Grimshaw, James,Hewitt, S. Armstrong
-
p. 2995 - 2998
(2007/10/02)
-
- NEW METHODS FOR THE SYNTHESIS OF 2-ARYLPYRROLES
-
Two short and efficient synthetic approaches for -mostly unknown- 2-arylpyrroles are presented.The key intermediates 3 are conveniently obtained from commercially available acetophenones 5 (method I) or benzoic acid derivatives 10, 11 (method II).
- Kruse, Chris G.,Bouw, Jan P.,Hes, Roelof van,Kuilen, Aalt van de,Hartog, Jack A. J. den
-
p. 3141 - 3151
(2007/10/02)
-