Catalytic Asymmetric exo′-Selective [3+2] Cycloaddition of Iminoesters with Nitroalkenes
作者:Takayoshi Arai、Naota Yokoyama、Asami Mishiro、Hiroyasu Sato
DOI:10.1002/anie.201004098
日期:2010.10.18
Under control: A chiral imidazoline–aminophenol/Ni(OAc)2 complex promotes the first catalyticasymmetric exo′‐selective [3+2] cycloaddition of iminoesters and nitroalkenes. Thermodynamic control over the stepwise Michael/Mannich cyclization steps gives the adducts in up to 99 % ee.
Discovering Biomolecules with <i>Huisgenase</i> Activity: Designed Repeat Proteins as Biocatalysts for (3 + 2) Cycloadditions
作者:Iván Rivilla、Mikel Odriozola-Gimeno、Antonio Aires、Ana Gimeno、Jesús Jiménez-Barbero、Miquel Torrent-Sucarrat、Aitziber L. Cortajarena、Fernando P. Cossío
DOI:10.1021/jacs.9b06823
日期:2020.1.15
Designed repeat proteins catalyze the 1,3-dipolar reaction between an imine and a deficient dipolarophile in THF solution to form unnatural nitroproline esters, a reaction that no enzyme can catalyze. NMR studies and mutation experiments show that both acidic and basic residues can catalyze the reaction. The diastereocontrol of the reaction depends on the flexibility of the protein and on the number