1565852-75-6Relevant academic research and scientific papers
Organocatalytic asymmetric [4+2] cyclization of 2-benzothiazolimines with azlactones: Access to chiral benzothiazolopyrimidine derivatives
Ni, Qijian,Wang, Xuyang,Xu, Fangfang,Chen, Xiaoyun,Song, Xiaoxiao
, p. 3155 - 3158 (2020/03/23)
An organocatalytic asymmetric domino Mannich/cyclization reaction between 2-benzothiazolimines with azlactones has been successfully developed. With the bifunctional squaramide catalyst, this formal [4+2] cyclization occurs with good to high yields and excellent stereoselectivities (up to 99% ee, >20?:?1 dr), providing an efficient and mild access to chiral benzothiazolopyrimidines bearing adjacent tertiary and quaternary stereogenic centers.
Enantioselective synthesis of dihydrocoumarin derivatives by chiral scandium(iii)-complex catalyzed inverse-electron-demand hetero-Diels-Alder reaction
Hu, Haipeng,Liu, Yangbin,Guo, Jing,Lin, Lili,Xu, Yali,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 3835 - 3837 (2015/03/31)
An asymmetric inverse-electron-demand hetero-Diels-Alder reaction between o-quinone methides and azlactones to generate potentially pharmacological active dihydrocoumarins has been achieved efficiently by using a chiral N,N′-dioxide-Sc(iii) complex as the catalyst. The desired products were obtained in high yields with excellent enantioselectivities and diastereoselectivities (up to 94% yield, 96% ee and >19:1 dr) under mild reaction conditions. A concerted reaction pathway was confirmed by Operando IR and control experiments.
Alkynyliodonium salt mediated alkynylation of azlactones: Fast access to Cα-tetrasubstituted α-amino acid derivatives
Finkbeiner, Peter,Weckenmann, Nicole M.,Nachtsheim, Boris J.
supporting information, p. 1326 - 1329 (2014/04/03)
An efficient electrophilic alkynylation of azlactones (oxazol-5(4H)-ones) is developed using alkynyl(phenyl)iodonium salts as the electrophilic alkyne source. After remarkably short reaction times, the desired alkyne functionalized azlactones are obtained in 60-97% yield and can be transformed easily into a variety of quaternary α-amino acid derivatives.
