The bis-1,4-dimesityl-1,2,3-triazol-5-ylidene–palladium complex (1a) successfully catalyzes the Mizoroki–Heck and Sonogashira coupling reactions with aryl bromides to give the corresponding alkenes and alkynes, respectively, in good to excellent yields. In the Mizoroki–Heck reaction, electron-rich, electron-poor, and functionalized aryl bromides and alkenes are tolerated, while the substrates are limited
irradiation has been shown to have a beneficial effect on catalyst preparation. The catalyst exhibited excellent activity in ligand‐free C−C Suzuki and Heck couplings with a large number of aryl iodide and bromides, in which microwave irradiation use cuts down reaction time. Pd/Si‐CD have shown high activity and selectivity in the hydrogenationreaction, and the semihydrogenation of phenyl acetylene was also
Palladium-Catalyzed Desulfitative Mizoroki-Heck Couplings of Sulfonyl Chlorides with Mono- and Disubstituted Olefins: Rhodium-Catalyzed Desulfitative Heck-Type Reactions under Phosphine- and Base-Free Conditions
作者:Srinivas Reddy Dubbaka、Pierre Vogel
DOI:10.1002/chem.200400838
日期:2005.4.22
olefins with arenesulfonyl and trifluoromethanesulfonyl chlorides. Thus (E)-1,2-disubstituted alkenes with high stereoselectivity and 1,1,2-disubstituted alkenes with 12:1 to 21:1 E/Z steroselectivity can be obtained. Herrmann's palladacycle at 0.1 mol % is sufficient to catalyze these reactions, for which electron-rich or electron-poor sulfonylchlorides and alkenes are suitable. If phosphine- and base-free
Pd(OAc)<sub>2</sub>/DABCO as a Highly Active Catalytic System for the Heck Reaction
作者:Jin-Heng Li、De-Ping Wang、Ye-Xiang Xie
DOI:10.1055/s-2005-869980
日期:——
The combination of Pd(OAc)2 and DABCO (triethylenediamine) was observed as an efficient catalytic system for the Heck cross-coupling reaction. In the presence of Pd(OAc)2 and DABCO, a number of ArX (X = I, Br, and Cl) were coupled with olefins efficiently and selectively to afford the corresponding unsymmetric internal olefins in good to excellent yields. Furthermore, the Pd(OAc)2/DABCO-catalyzed Heck cross-coupling reaction provided high TONs up to 1,000,000.
An efficient palladium catalyzed Mizoroki–Heck cross-coupling in water
作者:Sanjay N. Jadhav、Chandrashekhar V. Rode
DOI:10.1039/c7gc02869e
日期:——
Pd-catalysed Mizoroki–Heck coupling reaction was successfully performed in water in the absence of any additives under aerobic conditions. The various key reaction parameters that affect the yield of the desired cross-coupling product were optimized. The Pd(PPh3)4/Et3N/H2O/98 °C catalyst system was found to be highly active (TOF = 12 to 14 h−1) towards achieving excellent yield of the Mizoroki–Heck coupling
在有氧条件下,在没有任何添加剂的情况下,水中成功地进行了均相Pd催化的Mizoroki-Heck偶联反应。优化了影响所需交叉偶联产物收率的各种关键反应参数。发现Pd(PPh 3)4 / Et 3 N / H 2 O / 98°C催化剂体系具有很高的活性(TOF = 12至14 h -1),可实现出色的Mizoroki–Heck偶联产物的收率。在最短的反应时间内,吸电子以及给电子的芳基溴化物和氯化物种类繁多。钯(PPh 3)4对Mizoroki-Heck偶联反应过程中的催化剂失活进行了研究,并发展了实现十倍Pd-金属可循环性而又没有明显损失其活性的策略。因此,提出的机制提供了在水性介质中接触各种烯烃的途径,从而使该协议变得环保。