Asymmetric Ion-Pairing Catalysis of the Reversible Cyclization of 2′-Hydroxychalcone to Flavanone: Asymmetric Catalysis of an Equilibrating Reaction
作者:Lukas Hintermann、Claudia Dittmer
DOI:10.1002/ejoc.201200838
日期:2012.10
The asymmetric catalytic cyclization of the simple 2′-hydroxychalcone (1) to flavanone (2), a model for the chalcone isomerase reaction, has been realized as a catalytic asymmetric ion-pairing process with chiral quaternary ammonium salts (e.g., 9-anthracenylmethlycinchoninium chloride; 9-Am-CN-Cl) and NaH as small-molecule co-catalyst. In toluene/CHCl3 solution, the process reaches an intrinsic enantioselectivity
Enhanced reactivity and selectivity of asymmetric oxa-Michael addition of 2′-hydroxychalcones in carbon confined spaces
作者:Melad Shaikh、Kiran Kumar Atyam、Mahendra Sahu、Kalluri V. S. Ranganath
DOI:10.1039/c7cc01096f
日期:——
Carbon nanotubes (CNTs) are employed as nanoscale reaction vessels for the asymmetric oxa-Michael addition of 2′-hydroxychalcones.
碳纳米管(CNTs)被用作纳米级反应容器,用于2'-羟基香豆素的不对称氧-迈克尔加成反应。
Enantioselective biomimetic cyclization of 2′-hydroxychalcones to flavanones
作者:Yan-Lei Zhang、Yong-Qiang Wang
DOI:10.1016/j.tetlet.2014.04.032
日期:2014.5
developed and shown to catalyze the direct and highly enantioselective cyclization of 2′-hydroxychalcones in imitation of the natural process of chalcone cyclization. The straightforward synthetic process occurs under mild reaction conditions, tolerates moisture and air, and gives an enantiomeric excess up to 99%. This approach provides a facile and efficient access to chiral flavanones.