100372-58-5Relevant academic research and scientific papers
Novel triethylamine mediated thermal reactions of 3-aryl-2-cyanoprop-2-enoic acid derivatives - Demethylation, reduction and vinylogation
Harisha, Attimogae Shivamurthy,Nayak, Suresh Parameshwar,Nagarajan, Kuppuswamy,Guru Row, Tayur Narasingarow,Hosamani, Amar A.
, p. 1427 - 1431 (2015)
3-Aryl-2-propenoic acid derivatives undergo interesting reactions with hot triethylamine. Substrates like 6 having a methoxyl with a nitro in the ortho and cyanoacrylic derivatives in the para positions give O-demethylated products, for example, entacapone 7. On the other hand compounds like 16 having the NO2 in the para and cyanoacrylic in the ortho position undergo reduction and vinylogation. The latter phenomenon is observed in the absence of the NO2 group also.
Reaction of 3-arylidenepropenoic acid derivatives with triethylamine and other amines; Unexpected reductions and vinylogations
Harisha, Attimogae Shivamurthy,Nayak, Suresh Parameshwar,Nagarajan, Kuppuswamy,Row, Tayur Narasingarow Guru,Hosamani, Amar A.
, p. 2880 - 2889 (2016/05/24)
Exposure of ethyl 2-cyano-3-(2-methoxy-5-nitrophenyl)acrylate 1f to triethylamine in hot ethanol resulted in the formation of the dihydro derivative 2f and vinylogue 3f in high yields. Single crystal X-ray data are provided for 3f. Similar reactions were observed for various analogues. The reaction was studied changing aryl substituent, amines and solvents. Pyridyl, thienyl analogues were also examined. The study was extended to cyclic molecules incorporating such systems like thiazolidinedione 8, 3-cyanocoumarin 9 and 4-arylidene-isoquinoline-2,4-diones 11. The last group gave vinylogated products, 4-cinnamylidene-isoquinolinediones and 4-hydroxylated species. A few examples of arylidene derivatives from malononitrile, ethyl acetoacetate, acetyl acetone and ethyl methylsufonylacetate were investigated. Ethyl cinnamate and β-nitrostyrene were unaffected. The reaction is considered to be possibly radical mediated, since addition of free radical quencher suppressed the reaction. Contrary to the effects of thermal conditions, irradiation of 1f in ethanol at 254 and 365 nm gave complex mixtures. A few other interesting observations in this study are noted: vinylogation of 1f with acetaldehyde to 3f; formation of 3f from 1f by the treatment with triethylamine, palladium carbon and reduction of 1f to 2f by triethylammonium formate in DMF.
Overturning established chemoselectivities: Selective reduction of arenes over malonates and cyanoacetates by photoactivated organic electron donors
Doni, Eswararao,Mondal, Bhaskar,O'Sullivan, Steven,Tuttle, Tell,Murphy, John A.
supporting information, p. 10934 - 10937 (2013/08/23)
The prevalence of metal-based reducing reagents, including metals, metal complexes, and metal salts, has produced an empirical order of reactivity that governs our approach to chemical synthesis. However, this reactivity may be influenced by stabilization of transition states, intermediates, and products through substrate-metal bonding. This article reports that in the absence of such stabilizing interactions, established chemoselectivities can be overthrown. Thus, photoactivation of the recently developed neutral organic superelectron donor 5 selectively reduces alkyl-substituted benzene rings in the presence of activated esters and nitriles, in direct contrast to metal-based reductions, opening a new perspective on reactivity. The altered outcomes arising from the organic electron donors are attributed to selective interactions between the neutral organic donors and the arene rings of the substrates.
One-pot approach for C-C bond formation through ruthenium-amido complex catalyzed tandem aldol reaction/hydrogenation
Sun, Haifeng,Ye, Deju,Jiang, Hualiang,Chen, Kaixian,Liu, Hong
supporting information; experimental part, p. 2577 - 2582 (2010/09/05)
A one-pot novel and efficient approach was developed for the -alkylation of various nitriles with carbonyl compounds using ruthenium-amido complex catalyst 1. The C-C bond was formed through aldol reaction followed by hydrogenation with triethylamine-formic acid (TEAF) and 1. Moderate to high yields were obtained, and a variety of functional groups were tolerated, including nitro and chloro groups, and a furan ring. Georg Thieme Verlag Stuttgart New York.
