[EN] CYCLOPROPENIMINE CATALYST COMPOSITIONS AND PROCESSES<br/>[FR] COMPOSITIONS CATALYTIQUES À BASE DE CYCLOPROPÉNIMINE ET PROCÉDÉS
申请人:UNIV COLUMBIA
公开号:WO2013059118A1
公开(公告)日:2013-04-25
The present invention provides, inter alia, a cyclopropenimine Brønsted base catalyst and a cyclopropenimine scaffold for use as a Brønsted base catalyst. This cyclopropenimine has the structure (100). Methods for making such a cyclopropenimine are also provided. Further provided are processes for carrying out an organic synthetic reaction and processes for catalyzing a proton transfer reaction enantioselectively using such a cyclopropenimine Brønsted base catalyst.
Expanding the Toolbox of Heterogeneous Asymmetric Organocatalysts: Bifunctional Cyclopropenimine Superbases for Enantioselective Catalysis in Batch and Continuous Flow
作者:Costanza Leonardi、Arianna Brandolese、Lorenzo Preti、Olga Bortolini、Eleonora Polo、Paolo Dambruoso、Daniele Ragno、Graziano Di Carmine、Alessandro Massi
DOI:10.1002/adsc.202100757
日期:2021.12.21
A strategy for the immobilization of chiral 2,3-bisaminocyclopropenium salt (pre-catalyst) onto polystyrene and silica supports is presented together with a suitable procedure for the conversion into the corresponding cyclopropenimine superbase catalysts. The activity and recyclability of polystyrene- and silica-supported cyclopropenimines were initially tested under batch conditions in a model Michael
将手性 2,3-双氨基环丙烯盐(预催化剂)固定在聚苯乙烯和二氧化硅载体上的策略以及用于转化为相应环丙烯亚胺超强碱催化剂的合适程序。聚苯乙烯和二氧化硅负载的环丙烯亚胺的活性和可回收性最初是在分批条件下在迈克尔加成模型中测试的,检测出可比较的效率,但后者多相催化剂具有优异的稳定性(5 个循环,累积 TON 为 27.1)。在甘氨酸亚胺与不同迈克尔受体的反应中,优选的二氧化硅负载的环丙烯亚胺的表现与可溶性对应物非常相似(48-92% 产率;60-98% ee),它可以用作制造固定床中反应器(耐压不锈钢柱)的填充材料。连续流实验具有令人满意的长期稳定性(运行 24 小时),转换效率和对映选择性不变。
Development of new asymmetric two-center catalysts in phase-transfer reactions
A new asymmetric two-center phase-transfercatalyst was designed and a catalyst library containing more than 40 new two-center catalysts was constructed. The catalysts were applied in phase-transferalkylations and Michael additions to afford the corresponding products in up to 93% ee and 82% ee, respectively.
was used in phase-transfer alkylations and Michael additions to afford various opticallyactive α-amino acid equivalents in up to 93% yield. Moreover, dramatic counter anion effects were observed in phase-transfer catalysis (PTC) for the first time, making it possible to further improve reactivity and selectivity. These findings validate the usefulness of three-dimensional fine-tuning of the catalyst
CYCLOPROPENIMINE CATALYST COMPOSITIONS AND PROCESSES
申请人:THE TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF NEW YORK
公开号:US20140288323A1
公开(公告)日:2014-09-25
The present invention provides, inter alia, a cyclopropenimine Brønsted base catalyst and a cyclopropenimine scaffold for use as a Brønsted base catalyst. This cyclopropenimine has the structure (100). Methods for making such a cyclopropenimine are also provided. Further provided are processes for carrying out an organic synthetic reaction and processes for catalyzing a proton transfer reaction enantioselectively using such a cyclopropenimine Brønsted base catalyst.