A Palladium NNC-Pincer Complex as an Efficient Catalyst Precursor for the Mizoroki-Heck Reaction
A Palladium NNC-Pincer Complex as an Efficient Catalyst Precursor for the Mizoroki-Heck Reaction
复制标题
DOI：
10.1002/adsc.201800099
复制
发表时间：
2018-05-02
影响因子：
5.4
通讯作者：
Uozumi, Yasuhiro
中科院分区：
文献类型：
--
作者：
Hamasaka, Go;Ichii, Shun;Uozumi, Yasuhiro
芳基卤化物（碘化物、溴化物或氯化物）与活化烯烃在Pd-NNC-钳形络合物存在下的Mizoroki-Heck反应在ppb至ppm的负载量下以优异的产率得到相应的内烯烃。总周转次数和周转频率分别达到8.70 × 10（8）和1.21 × 10（7）h（-1）（3.36 × 10（3）s（-1））。将该催化剂应用于10克规模的UV-B防晒剂奥西诺酯（4-甲氧基肉桂酸2-乙基己酯）的合成中。反应速率分析，反应混合物的透射电子显微镜检查，和中毒试验表明，单体钯物种是催化循环中的催化活性物种。
The Mizoroki-Heck reaction of aryl halides (iodides, bromides, or chlorides) with activated alkenes in the presence of a palladium NNC-pincer complex at ppb to ppm loadings gave the corresponding internal alkenes in excellent yields. The total turnover number and turnover frequency reached up to 8.70 x 10(8) and 1.21 x 10(7) h(-1) (3.36 x 10(3) s(-1)), respectively. The catalyst was applied in a ten-gram-scale synthesis of the UV-B sunscreen agent octinoxate (2-ethylhexyl 4-methoxycinnamate). Reaction-rate analyses, transmission electron microscopic examination of the reaction mixture, and poisoning tests suggested that a monomeric palladium species is the catalytically active species in the catalytic cycle.