Well-Defined Noble Metal Single Sites in Zeolites as an Alternative to Catalysis by Insoluble Metal Salts
作者:Paula Rubio-Marqués、Miguel A. Rivero-Crespo、Antonio Leyva-Pérez、Avelino Corma
DOI:10.1021/jacs.5b07304
日期:2015.9.16
that the resting insoluble metal is catalytically useless. To circumvent this waste of precious metal and follow a rational design, we generate here well-dispersed Pt(II) and Pd(II) single sites on zeolite Y, with an exquisite control of the Lewis acidity, to catalyze different hydroaddition reactions to alkynes and alkenes with up to 10(4) catalytic cycles (at least 2 orders of magnitude superior to
聚合形式的不溶性贵金属氯化物(即 PtCl2、PdCl2、AuCl、RhCl3)通常用作溶液中大量有机反应的催化剂。在这里,我们表明只有这些贵金属氯化物的少量可溶部分(通常为 5-30%)对炔烃和烯烃的加氢胺化、加氢烷氧基化、氢化硅烷化和环异构化具有催化活性,而其余的不溶性金属在催化上是无用的。为了避免这种贵金属的浪费并遵循合理的设计,我们在沸石 Y 上生成了分散良好的 Pt(II) 和 Pd(II) 单点,并巧妙地控制了路易斯酸度,
CHEMICAL COMPOUNDS
申请人:Evindar Ghotas
公开号:US20100009936A1
公开(公告)日:2010-01-14
The invention provides compounds formula I, their preparation, and their use as pharmaceutically active immuno-suppressive agents for the treatment of autoimmune disorders, organ transplant rejection, disorders associated with an activated immune system, as well as other disorders modulated by lymphopenia or SIP receptors.
The invention provides compounds formula I, their preparation, and their use as pharmaceutically active immunosuppressive agents for the treatment of autoimmune disorders, organ transplant rejection, disorders associated with an activated immune system, as well as other disorders modulated by lymphopenia or S1P receptors.
<i>tert</i>-Butyl Nitrite Promoted Oxidative Intermolecular Sulfonamination of Alkynes to Synthesize Substituted Sulfonyl Pyrroles from the Alkynylamines and Sulfinic Acids
作者:Zhenjie Qi、Yong Jiang、Yanyan Wang、Rulong Yan
DOI:10.1021/acs.joc.8b00741
日期:2018.8.3
tert-Butyl nitrite promoted oxidative intermolecular sulfonamination of alkynes to synthesize substituted sulfonyl pyrroles from the alkynylamines and sulfinic acids via tandem addition/cyclization was developed. This reaction is performed well by employing tert-butyl nitrite as the oxidant, and various substituted sulfonyl pyrroles are formed in moderate to good yields with no requirement of metal catalysis.