51144-98-0Relevant academic research and scientific papers
Direct C2-arylation ofN-acyl pyrroles with aryl halides under palladium catalysis
Chen, Weiqiang,Li, Hui-Jing,Cheng, Yun-Fei,Wu, Yan-Chao
supporting information, p. 1555 - 1564 (2021/03/01)
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.
Direct oxidative coupling of: N -acyl pyrroles with alkenes by ruthenium(ii)-catalyzed regioselective C2-alkenylation
Chen, Weiqiang,Li, Hui-Jing,Li, Qin-Ying,Wu, Yan-Chao
supporting information, p. 500 - 513 (2020/01/30)
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.
Synthesis of N -Sulfonyl- and N -Acylpyrroles via a Ring-Closing Metathesis/Dehydrogenation Tandem Reaction
Chen, Weiqiang,Li, Hui-Jing,Liu, Ying,Nan, Xiang,Wu, Yan-Chao,Zhang, Yin-Lin
, p. 3651 - 3666 (2019/09/30)
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
Cyclopentadienyl-free rare-earth metal amides [{(CH2SiMe 2){(2,6iPr2C6H3)N} 2}Ln{N(SiMe3)2}(THF)] as highly efficient versatile catalysts for C-C and C-N bond formation
Wu, Yunjun,Wang, Shaowu,Zhang, Lijun,Yang, Gaosheng,Zhu, Xiancui,Zhou, Zhihong,Zhu, Hong,Wu, Shihong
supporting information; experimental part, p. 326 - 332 (2010/04/06)
Efficient methods have been developed for the direct synthesis of amides from aldehydes and a straightforward route to propiolamidines using cyclopentadienyl-free rare-earth metal amides [{(CH2SiMe 2){(2,6-iPr2C6H3)N} 2}Ln{N(SiMe3)2}(THF)] [Ln = Yb (1), Y (2), Dy (3), Sm (4), Nd (5)] as versatile catalysts, The results indicate that in the direct synthesis of amides from aldehydes the catalysts have the activity order 2>1~3~4~5. These methods have the advantage of easy preparation of the catalysts, low catalyst loading, high conversion of substrates to products, mild reaction conditions, and compatibility with a wide range of substrates.
Synthesis and nuclear magnetic resonance spectroscopic studies of 1- arylpyrroles
Lee, Chang Kiu,Jun, Jung Ho,Yu, Ji Sook
, p. 15 - 24 (2007/10/03)
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.
A new method to N-arylmethylenepyrroles from N-acylpyrroles
D'Silva, Claudius,Iqbal, Rifat
, p. 457 - 458 (2007/10/03)
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.
A facile synthesis of N-substituted pyrroles
Fang,Leysen,Ottenheijm
, p. 1857 - 1861 (2007/10/02)
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.
