5472-61-7Relevant academic research and scientific papers
Pd(II)-catalyzed C(sp3)-H arylation of amino acid derivatives with click-triazoles as removable directing groups
Zhang, Guofu,Xie, Xiaoqiang,Zhu, Jianfei,Li, Shasha,Ding, Chengrong,Ding, Ping
, p. 5444 - 5449 (2015/05/20)
By using click-triazoles as conveniently approachable and removable directing groups, the direct palladium-catalyzed C(sp3)-H arylation of amino acid derivatives with various aryl iodides bearing different electronic properties has been achieved. Notably, the desired amino acid molecule can be obtained by the cleavage of the tethered click-triazoles after the catalytic reaction, which aims to provide a practical protocol for the accessibility of both natural and synthetic amino acids.
Neighbouring group effects promote substitution reactions over elimination and provide a stereocontrolled route to chloramphenicol
Easton, Christopher J.,Hutton, Craig A.,Merrett, Martin C.,Tiekink, Edward R. T.
, p. 7025 - 7036 (2007/10/03)
In reactions of β-brominated valine and p-nitrophenylalanine derivatives to give β-hydroxy amino acid derivatives the carboxyl group, when protected as an amide, exerts a neighbouring group effect to facilitate the substitution process, and reduce competing elimination reactions. As a consequence of the effect, the (2R,3R)- and (2R,3S)-stereoisomers of 3-bromo-N-tert-butyl-N(α)-phthaloyl-p-nitrophenylalaninamide both react to give (2S,3R)-3-hydroxy-N-tert-butyl-N(α)-phthaloyl-p-nitrophenylalaninamid e, providing a stereoconvergent route to chloramphenicol.
