of unactivated alkenes using ethanol as the hydrogen source is described. A new NCP-type pincer iridium complex (BQ-NCOP)IrHCl containing a rigid benzoquinoline backbone has been developed for efficient, mild TH of unactivated C-C multiple bonds with ethanol, forming ethyl acetate as the sole byproduct. A wide variety of alkenes, including multisubstituted alkyl alkenes, aryl alkenes, and heteroatom-substituted
描述了使用乙醇作为氢源实现未活化烯烃的转移氢化 (TH) 的第一种通用催化方法。已经开发出一种新的 NCP 型钳形铱络合物 (BQ-NCOP)IrHCl,其含有刚性苯并喹啉主链,可有效、温和地将未活化的 CC 多键与乙醇进行 TH,形成乙酸乙酯作为唯一的副产品。各种烯烃,包括多取代的烷基烯烃、芳基烯烃和杂原子取代的烯烃,以及含 O 或 N 的杂芳烃和内部炔烃,都是合适的底物。重要的是,(BQ-NCOP)Ir/EtOH 系统在反应性官能团(如酮和羧酸)存在下对烯烃氢化表现出高化学选择性。此外,与 C2D5OD 的反应为氘标记化合物提供了一条便捷的途径。详细的动力学和机理研究表明,单取代烯烃(如 1-辛烯、苯乙烯)和多取代烯烃(如环辛烯 (COE))表现出基本的机理差异。乙醇的 OH 基团在苯乙烯反应中显示出正常的动力学同位素效应 (KIE),但在 COE 的情况下显示出显着的反向 KIE。对
Homogeneous Hydrogenation with a Cobalt/Tetraphosphine Catalyst: A Superior Hydride Donor for Polar Double Bonds and <i>N</i>-Heteroarenes
The development of catalysts based on earth abundant metals in place of noble metals is becoming a central topic of catalysis. We herein report a cobalt/tetraphosphine complex catalyzed homogeneous hydrogenation of polar unsaturated compounds using an air- and moisture-stable and scalable precatalyst. By activation with potassium hydroxide, this cobalt system shows both high efficiency (up to 24000
The present invention relates to compounds of general formula IA or IB
wherein
X
1
and X
2
are each independently N or C—R″ and
R
1
, R
2
,R
3
, R
4
,
R
5
, and R
6
are as defined in the specification and to pharmaceutically acceptable acid addition salts thereof. The compounds can be used for the treatment of diseases related to the glycine transporter inhibitor, such as schizophrenia and Alzheimer's disease.
Boric acid catalyzed chemoselective reduction of quinolines
作者:Dipanjan Bhattacharyya、Sekhar Nandi、Priyanka Adhikari、Bikash Kumar Sarmah、Monuranjan Konwar、Animesh Das
DOI:10.1039/c9ob02673h
日期:——
Boricacid promoted transfer hydrogenation of substituted quinolines to synthetically versatile 1,2,3,4-tetrahydroquinolines (1,2,3,4-THQs) was described under mild reaction conditions using a Hantzsch ester as a mild organic hydrogen source. This methodology is practical and efficient, where isolated yields are excellent and reducible functional groups are well tolerated in the N-heteroarene moiety