422570-19-2Relevant articles and documents
Temperature-Dependent Enantio- and Diastereodivergent Synthesis of Amino Acids with One or Multiple Chiral Centers
Fan, Shiming,Liu, Shouxin,Zhu, Sufang,Feng, Juan,Zhang, Zhiwei,Huang, Jing
, p. 4660 - 4663 (2017)
A general and facile methodology for temperature-dependent enantiodivergent and diastereodivergent synthesis of amino acids with one or multiple chiral centers was developed. Camphor-based tricyclic iminolactones attack electrophiles from the endo face at low temperature (-78 to -40 °C) and from the exo face at high temperature (-10 to 25 °C).
Chiral tricyclic iminolactone derived from (1R)-(+)-camphor as a glycine equivalent for the asymmetric synthesis of α-amino acids
Xu, Peng-Fei,Chen, Yuan-Shek,Lin, Shu-I,Lu, Ta-Jung
, p. 2309 - 2314 (2007/10/03)
The development of a highly efficient and stereoselective methodology for the preparation of α-amino acids is described. The chiral template, tricyclic iminolactone 7, was synthesized from (1R)-(+)-camphor in five steps in 50% overall yield. Alkylation of iminolactone 7 afforded the α-monosubstituted products in good yields (74-96%) and excellent diastereoselectivities (>98%). Hydrolysis of the alkylated iminolactones furnished the desired α-amino acids in good yields and enantioselectivities with nearly quantitative recovery of the chiral auxiliary 4.