137967-01-2Relevant academic research and scientific papers
One-Pot Synthesis of β,β-Disubstituted α,β-Unsaturated Carbonyl Compounds
Sugiura, Masaharu,Ashikari, Yasuhiko,Nakajima, Makoto
, p. 8830 - 8835 (2015/09/15)
TiCl4-promoted aldol reaction of ketones as aldol acceptors followed by elimination of the titanoxy group from the Ti-aldolates affords β,β-disubstituted α,β-unsaturated carbonyl compounds in a one-pot procedure. The use of additives, such as DMF, N,N,N′,N′-tetramethylethylenediamine, and pyridine, in the elimination step was found to be important.
Asymmetric conjugate reduction of α,β-unsaturated ketones and esters with chiral rhodium(2,6-bisoxazolinylphenyl) catalysts
Kanazawa, Yoshinori,Tsuchiya, Yasunori,Kobayashi, Kazuki,Shiomi, Takushi,Itoh, Jun-Ichi,Kikuchi, Makoto,Yamamoto, Yoshihiko,Nishiyama, Hisao
, p. 63 - 71 (2007/10/03)
New asymmetric conjugate reduction of β,β-disubstituted α,β-unsaturated ketones and esters was accomplished with alkoxylhydrosilanes in the presence of chiral rhodium(2,6-bisoxazolinylphenyl) complexes in high yields and high enantioselectivity. (E)-4-Phenyl-3-penten-2- one and (E)-4-phenyl-4-isopropyl-3-penten-2-one were readily reduced at 60°C in 95% ee and 98 % ee, respectively, by 1 mol % of catalyst loading. (EtO) 2MeSiH proved to be the best hydrogen donor of choice. tert-Butyl (E)-β-methylcinnamate and β-isopropylcinnamate could also be reduced to the corresponding dihydrocinnamate derivatives up to 98% ee.
Multicomponent synthesis of dihydropyrimidines and thiazines
Vugts, Danielle J.,Koningstein, Manoe M.,Schmitz, Rob F.,De Kanter, Frans J. J.,Groen, Marinus B.,Orru, Romano V. A.
, p. 7178 - 7189 (2007/10/03)
A broad range of differently substituted dihydropyrimidines and thiazines can be efficiently prepared by using a four-component reaction between phosphonates, nitriles, aldehydes, and iso(thio)cyanates. The scope and limitations of this multicomponent reaction are fully described. Variation of all four components has been investigated. The nitrile and aldehyde inputs can be varied extensively, but variation of the phosphonate input remains limited. An interesting rearrangement leading to phosphoramidates has been observed, Furthermore, the multicomponent reaction seems to be restricted to the use of isocyanates with strongly electron-withdrawing substituents, but an interesting additional exchange reaction under microwave conditions leads to dihydropyrimidines with less electron-withdrawing substituents at N3. In addition, a diastereoselective formation of dihydropyrimidines has been observed when using a chiral aldehyde as the input. Finally, by changing the isocyanate component to an isothiocyanate, thiazines are efficiently formed instead of the corresponding thio-dihydropyrimidines.
Functional Group Hybrids. Reactivity of α'-Nucleofuge α,β-Unsaturated Ketones. 1. Reactions with Organocopper Reagents
Barbee, Thomas R.,Albizati, Kim F.
, p. 6764 - 6773 (2007/10/02)
A series of α-nucleofuge α',β'-unsaturated ketones encompassing a variety of structural types and nucleofuges was prepared.Treatment of these compounds with lithium dimethylcuprate or methylcopper leads primarily to either reductive cleavage of the α-nucl
