Vaulted Biaryls in Catalysis: A Structure-Activity Relationship Guided Tour of the Immanent Domain of the VANOL Ligand
作者:Yong Guan、Zhensheng Ding、William D. Wulff
DOI:10.1002/chem.201302451
日期:2013.11.11
anion (boroxinate) that is assembled in situ from three equivalents of B(OPh)3 and one of the VANOLligand by a molecule of substrate. The substrates are bound to the boroxinate by H bonds to oxygen atoms O1–O3. The effects of introducing substituents at each position of the naphthalene core of the VANOLligand are systematically investigated in an aziridination reaction. Substituents in the 4,4′‐ and
A practical procedure for catalytic asymmetric synthesis of opticallyactive arylglycine derivatives viaopticallyactive α-aminonitriles has been developed. The N-benzhydryl α-arylaminonitrile intermediates were prepared in excellent yield (89–99%) and enantiomeric purity (96 to >98% ee) by enantioselective cyanation of aldimines with TMSCN/iPrOH in the presence of 2.5 mol % of an easily prepared
Catalytic Asymmetric Aziridination of Benzhydryl Imines and Diazoacetate Esters with BOROX Catalysts from 3,3′-Disubstituted VANOL Ligands
作者:William D. Wulff、Yong Guan、Zhenjie Lu、Xiaopeng Yin、Aliakbar Mohammadlou、Richard J. Staples
DOI:10.1055/s-0039-1690860
日期:2020.7
into boroxinate catalysts that were used to screen the catalytic asymmetric aziridination of benzhydryl imines with ethyldiazoacetate. Each catalyst was screened in the reaction of imines generated from benzaldehyde and cyclohexanecarboxaldehyde and some with 4-nitro- and 4-methoxybenzaldehyde. In addition, the first report of the effect of the ester substituent of the diazoacetate ester on the asymmetric
Brønsted acid activation of α-diazo imide: a syn-selective glycolate Mannich reaction
作者:Timothy L. Troyer、Hubert Muchalski、Jeffrey N. Johnston
DOI:10.1039/b913785h
日期:——
A novel α-diazo imide reagent and its activation by strong Brønsted acid is shown to produce the product of a syn-glycolate Mannich transform with high diastereoselection.