2314-79-6Relevant academic research and scientific papers
Photoredox/Cobalt-Catalyzed C(sp3)-H Bond Functionalization toward Phenanthrene Skeletons with Hydrogen Evolution
Guo, Jia-Dong,Yang, Xiu-Long,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
supporting information, p. 9627 - 9632 (2020/12/21)
The first example of photoredox strategy for synthesis of phenanthrene skeletons through C(sp3)-H functionalization under external oxidant-free conditions is achieved. This transformation relies on the keto-enol tautomerism of 1,3 dicarbonyl moiety, i.e., the enol form of 1,3-dicarbonyl derivatives with relatively lower oxidation potential can be activated by the excited acridinium photocatalyst. The electron and proton eliminated from the substrate are immediately captured by a cobaloxime catalyst to exclusively afford a-carbonyl radical for highly substituted 10-phenanthrenols in good to excellent yields.
Synthesis of 3-(5-amino-1: H -1,2,4-triazol-3-yl)propanamides and their tautomerism
Lim, Felicia Phei Lin,Tan, Lin Yuing,Tiekink, Edward R. T.,Dolzhenko, Anton V.
, p. 22351 - 22360 (2018/07/03)
Two complementary pathways for the preparation of N-substituted 3-(5-amino-1H-1,2,4-triazol-3-yl)propanamides (5) were proposed and successfully realized in the synthesis of 20 representative examples. These methods use the same types of starting material
Synthesis of novel N-aryl-3-dialkylamino-4-substituted maleimides
Patil, Nilesh S.,Deshmukh, Ganesh B.,Mahale, Keshao A.,Gosavi, Kirankumar S.,Patil, Sambhaji V.
, p. 272 - 278 (2015/03/04)
The syntheses of several novel 3-dialkylamino-N-aryl-maleimides 3a-i and 6 are described via a conjugate elimination addition-elimination pathway. Syntheses of their various 4-substituted derivatives 4a-i, 5a-c and 7-12 are also described. Introduction of a secondary amino group at C-3 position in N-arylmaleimides leads to the formation of enaminones 3a-i and 6, which undergo facile electrophilic substitutions at C-4 position in good to excellent yields to provide the highly functionalized maleimides 4a-i, 5a-c and 7-12.
Open-air N-arylation of N-H heterocycles with arylboronic acids catalyzed by copper(II) Schiff base complexes
Islam,Dey, Ram Chandra,Roy, Anupam Singha,Paul, Sumantra,Mondal, Sanchita
, p. 961 - 969 (2015/01/09)
Two copper Schiff base complexes, in both homogeneous and heterogeneous forms, were prepared and characterized by using elemental analysis, FTIR, UV-Vis spectroscopy and scanning electron microscopy. The catalytic performances of these complexes were studied in the N-arylation of N-H heterocycles with arylboronic acids in methanol without any added base at 40 °C under open air. The effects of various parameters such as solvent and temperature on the reaction system were studied. The reaction is applicable to a wide variety of N-H heterocycles and arylboronic acids. The heterogeneous catalyst was recovered by simple filtration, and reusability experiments showed that this catalyst can be used five times without much loss in the catalytic activity.
A convenient one-pot synthesis of polysubstituted pyrroles from N-protected succinimides
Kobeissi, Marwan,Yazbeck, Ogaritte,Chreim, Yamama
supporting information, p. 2523 - 2526 (2014/05/06)
The dienamine products formed by the reaction between polysubstituted succinimides and the Petasis reagent were subjected to isomerization under mild acidic conditions to give polysubstituted pyrroles in excellent yields (85-95%). The scope and limitations of this methodology are explored.
An expeditious synthesis of imides from phthalic, maleic and succinic anhydrides and chemoselective C=C reduction of maleic amide esters
Kumar, Padam Praveen,Reddy, Y. Dathu,Kumari, Y. Bharathi,Devi, B. Rama,Dubey
, p. 392 - 398 (2014/05/06)
Phthalic, maleic and succinic anhydrides have been reacted with aromatic amines to obtain the corresponding monoacid monoamides. The latter have been each transformed into the corresponding cyclic imide derivatives by treating with SOCl2. Alternatively, anhydrides have been reacted with methanolic KOH to obtain monomethyl ester derivatives which on reaction with aromatic amines in the presence of EDC. HCl and HOBt give cyclic imide derivatives. Reaction of monoacid monoamides independently, with SOCl 2 at 0-5°C give the monoamide monoester derivatives. Treatment of monoamide monoester of malic anhydride with NaBH4 leads to the unusual reduction of C=C grouping as well as the carbonyl group of the ester group to from monoamide monoalcohol of succinic anhydride. Preparation of monoamide monoalcohol of succinic anhydride can also be achieved by chemoselective reduction of monoamide monoester of malic anhydride with Mg turnings yielding monoamide monoester of succinic anhydride followed by reduction of the latter with NaBH4.
A facile and green synthesis of N-substituted imides
Kumar, Padam Praveen,Rama Devi,Dubey
, p. 1166 - 1171 (2013/09/24)
Anhydrides 1, 6 and 10 have been reacted, independently, with aromatic primary amines 2 in solid phase by simple physical grinding of reactants with p-toluenesulphonicacid as a catalyst to yield corresponding open chain derivatives, monoacid monoamides3,7 and 11 respectively. The latter have each been transformed into the corresponding cyclic derivatives, i.e. imides 5, 9 and 13 respectively in solid phase by simple physical grinding of each with K 2CO3, alkylating agent and tetrabutylammoniumbromide as a catalyst with short reaction times. These cyclic imides can also be obtained by physical grinding of each of 3, 7 and 11 with dicyclohexylcarbodimide as a dehydrating agent in solid phase.
Studies on reactions of anhydrides with Schiff bases
Kumar, Padam Praveen,Mohiuddin,Rama Devi,Dubey
, p. 686 - 690 (2013/07/11)
Reaction of phthalic anhydride 1 with benzylidineanilines 2, in equimolar ratio in hot acetic acid, yields N-arylphthalimides 3. Compound 1 reacts with the arylimine part of the Schiff base eliminating benzaldehyde part 4 as the bye-product. This reaction of 1 with 2 is also found to occur with other anhydrides like succinic anhydride 5, maleic anhydride 7 and acetic anhydride 9 resulting in the formation of the corresponding N-arylimides, namely, succinicimide 6, maleicimide 8 and aceticimide 10 respectively. In all the above reactions, the by-product, i.e. benzaldehyde or p-chlorobenzaldehyde can be isolated and characterized as its 2,4-dinitrophenylhydrazone derivative. Probable mechanism for the formation of imides from the corresponding anhydrides and Schiff bases has been suggested.
Aromatic-amide-derived olefins as a springboard: Isomerization-initiated palladium-catalyzed hydrogenation of olefins and reductive decarbonylation of acyl chlorides with hydrosilane
Bai, Xing-Feng,Xu, Li-Wen,Zheng, Long-Sheng,Jiang, Jian-Xiong,Lai, Guo-Qiao,Shang, Jun-Yan
supporting information; experimental part, p. 8174 - 8179 (2012/08/27)
A highly efficient catalytic protocol for the isomerization of substituted amide-derived olefins is presented that successfully uses a hydride palladium catalyst system generated from [PdCl2(PPh3)2] and HSi(OEt)3. The Z to E isomerization was carried out smoothly and resulted in geometrically pure substituted olefins. Apart from the cis-trans isomerization of double bonds, the selective reduction of terminal olefins and activated alkenes was performed with excellent functional group tolerance in the presence of an amide-derived olefin ligand, and the products were obtained in high isolated yields (up to >99 %). Furthermore, the palladium/hydrosilane system was able to promote the reductive decarbonylation of benzoyl chloride when a (Z)-olefin with an aromatic amide moiety was used as a ligand. Copyright
