23784-70-5Relevant articles and documents
Copper(I)-Catalyzed Asymmetric 1,4-Conjugate Hydrophosphination of α,β-Unsaturated Amides
Li, Yan-Bo,Tian, Hu,Yin, Liang
supporting information, p. 20098 - 20106 (2021/01/01)
A catalytic asymmetric conjugate hydrophosphination of α,β-unsaturated amides is accomplished by virtue of the strong nucleophilicity of copper(I)-PPh2 species, which provides an array of chiral phosphines bearing an amide moiety in high to excellent yields with excellent enantioselectivity. Furthermore, the dynamic kinetic resolution of unsymmetrical diarylphosphines (HPAr1Ar2) is successfully carried out through the copper(I)-catalyzed conjugate addition to α,β-unsaturated amides, which affords P-chiral phosphines with good-to-high diastereoselectivity and high enantioselectivity. 1H NMR studies show that the precoordination of HPPh2 to copper(I)-bisphosphine complex is critical for the efficient deprotonation by Barton's Base. Moreover, the relative stability of the copper(I)-(R,RP)-TANIAPHOS complex in the presence of excessive HPPh2, confirmed by 31P NMR studies, is pivotal for the high asymmetric induction, as the ligand exchange between bisphosphine and HPPh2 would significantly reduce the enantioselectivity. At last, a double catalytic asymmetric conjugate hydrophosphination furnishes the corresponding product in high yield with high diastereoselectivity and excellent enantioselectivity, which is transformed to a chiral pincer palladium complex in moderate yield. This chiral palladium complex is demonstrated as an excellent catalyst in the asymmetric conjugate hydrophosphination of chalcone.
Palladium-catalyzed intermolecular addition of formamides to alkynes
Fujihara, Tetsuaki,Katafuchi, Yuko,Iwai, Tomohiro,Terao, Jun,Tsuji, Yasushi
supporting information; experimental part, p. 2094 - 2098 (2010/04/24)
A novel palladium system for an intermolecular addition of formamides to alkynes has been developed. The reaction of formamides with internal alkynes in the presence of a palladium catalyst with acid chloride as an additive afforded (E)-α,β-unsaturated amides regio- and stereoselectively. The same catalyst system realized the first example of the addition of formamides to terminal alkynes giving the corresponding α,β-unsaturated amides bearing a terminal methylene moiety as major products. The present reaction was widely applicable to substrates with various functionalities. This method also could be applied to the reaction of N,N-disubstituted formamides with norbornene. A hydridopalladium species would be formed as a key intermediate with in situ generated HCl under the reaction conditions.
A new synthesis of cinnamic acids from aromatic aldehydes and N,N-dimethylacetamide hydrochloride
Chiriac, Constantin I.,Tanasa, Fulga,Nechifor, Marioara
experimental part, p. 949 - 952 (2009/09/29)
Cinnamic acids have been prepared in 61-85% yields by a new synthesis from aromatic aldehydes and N, Ndimethylacetamide hydrochloride as reagent and solvent, at reflux (190-200°C), for 8-12 hours. Without N,N- dimethylacetamide hydrochloride this reaction is not possible.
