3082-69-7Relevant articles and documents
Enantioselective Synthesis of β-Amino Acid Derivatives Enabled by Ligand-Controlled Reversal of Hydrocupration Regiochemistry
Buchwald, Stephen L.,Guo, Sheng,Zhu, Jiaqi
supporting information, p. 20841 - 20845 (2020/09/16)
A Cu-catalyzed enantioselective hydroamination of α,β-unsaturated carbonyl compounds for the synthesis of β-amino acid derivatives was achieved through ligand-controlled reversal of the hydrocupration regioselectivity. While the hydrocupration of α,β-unsaturated carbonyl compounds to form α-cuprated species has been extensively investigated, we report herein that, in the presence of an appropriate ancillary chiral ligand, the opposite regiochemistry can be observed for cinnamic acid derivatives, leading to the delivery of the copper to the β-position. This copper can react with an electrophilic aminating reagent, 1,2-benzisoxazole, to provide enantioenriched β-amino acid derivatives, which are important building blocks for the synthesis of natural products and bioactive small molecules.
Chiral Lewis Base-Catalyzed, Enantioselective Reduction of Unprotected β-Enamino Esters with Trichlorosilane
Ye, Jianheng,Wang, Chao,Chen, Lin,Wu, Xinjun,Zhou, Li,Sun, Jian
supporting information, p. 1042 - 1047 (2016/04/19)
Catalytic asymmetric reduction of N-unsubstituted β-enamino esters represents a major challenge for asymmetric catalysis. In this paper, the first organocatalytic system that could be used for the asymmetric hydrosilylation of N-unsubstituted β-enamino esters has been developed. Using N-tert-butylsulfinyl-L-proline-derived amides and L-pipecolinic acid-derived formamides as catalyst, a broad range of β-aryl- and β-alkyl-substituted free β-amino esters could be prepared with high yields and enantioselectivities. The practicality was illustrated by the gram-scale asymmetric synthesis of ethyl (R)-3-amino-3-phenylpropanoate and isopropyl (S)-3-amino-4-(2,3,5-trifluorophenyl)butanoate. The resulting product can be smoothly transformed to the FDA approved medicines dapoxetine and sitagliptin in a short synthetic route.
Scalable scny BRAnthesis of β-amino esters via reformatskcny BRA reaction with N-tert-butanesulfincny BRAl imines
Brinner, Kristin,Doughan, Brandon,Poon, Daniel J.
experimental part, p. 991 - 993 (2009/10/10)
The Reformatskcny BRA reagents derived from ethcny BRAl bromoacetate and tert-butcny BRAl bromoacetate add cleanlcny BRA, in high cny BRAield, and with good diastereoselectivitcny BRA to N-tert-butanesulfincny BRAl aldimines and ketimines. Importantlcny BRA, this reaction scales well (>50 mmol), and affords products upwards of 70% cny BRAield over three steps, starting from commerciallcny BRA available N-tert-butanesulfinamide, aldehcny BRAdes, and ketones.
