A −CH2CH:C+NR2 synthon: Novel preparations of 1,3-disubstituted allylamines and of 1,2-diaryl pyrroles
摘要:
1-(3-Morpholinoprop-2-enyl)benzotriazole (1) is a useful synthon of the type [(CH2)-C---CH=C(+)NR(2)] as demonstrated by the preparation of allylamines 4. It can also provide a [(+ -) CH-CH=CH+] fragment for the synthesis of 1,2-diarylpyrroles 6.
Regioselective C-2 or C-5 Direct Arylation of Pyrroles with Aryl Bromides using a Ligand-Free Palladium Catalyst
作者:Julien Roger、Henri Doucet
DOI:10.1002/adsc.200900196
日期:——
acetyl or ester at the C-2 position of the pyrrole is tolerated. This environmentally attractive procedure has also been found to be tolerant to a very wide variety of functional groups on the arylbromides such as formyl, acetyl, propionyl, ester, nitrile, nitro, fluoro, methoxy, amino or trifluoromethyl.
Preparation of 1,2-Diaryl(heteroaryl)pyrroles and -3-methylpyrroles from <i>N</i>-Allylbenzotriazole
作者:Alan R. Katritzky、Lianhao Zhang、Jiangchao Yao、Olga V. Denisko
DOI:10.1021/jo000885x
日期:2000.11.1
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.
Additive-Free Palladium-Catalyzed Decarboxylative Cross-Coupling of Aryl Chlorides
作者:Ryan A. Daley、En-Chih Liu、Joseph J. Topczewski
DOI:10.1021/acs.orglett.9b01620
日期:2019.6.21
The cross-coupling of sodium (hetero)aryl carboxylates with (hetero)arylchlorides proceeds with 1 mol % palladium catalyst and does not require inorganic base, silver salts, or copper salts. This coupling uses two low energy partners, and the only stoichiometric byproducts are carbon dioxide and sodium chloride. The substrate scope includes less activated arylchlorides and carboxylates (>25 examples)
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 pyrrolesynthesis also provided the corresponding pyrrole derivatives
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
作者:Alan R. Katritzky、Hong Wu、Linghong Xie、Stanislaw Rachwal、Bogumila Rachwal、Jinlong Jiang、Guifen Zhang、Hengyuan Lang
DOI:10.1055/s-1995-4102
日期:1995.10
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-(benzotriazo-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.