描述了通过钌或铑络合物催化的N-苯基吡唑苯环中CH键的直接羰基化。在Ru 3(CO)12或Rh 4(CO)12存在下,N-苯基吡唑与一氧化碳和乙烯的反应导致苯环中邻位C-H键的位点选择性羰基化,得到相应的乙基酮。苯环上的各种官能团都是可以容忍的。基于p K a,N-苯基吡唑具有比预期更高的反应性吡唑共轭酸的分子量值。用于该反应的溶剂的选择是重要的,并且N,N-二甲基乙酰胺(DMA)给出了最好的结果。
Ruthenium-Catalyzed C−H/CO/Olefin Coupling Reaction of <i>N</i>-Arylpyrazoles. Extraordinary Reactivity of <i>N</i>-Arylpyrazoles toward Carbonylation at C−H Bonds
The reaction of 1-arylpyrazoles with CO and ethylene in the presence of Ru-3(CO)(12) resulted in regioselective carbonylation at the ortho C-H bonds. While it is found that the pyrazole ring also functions as the directing group for C-H bond cleavage, the efficiency of the reaction depends on the position of the pyrazole ring.
Ruthenium- and Rhodium-Catalyzed Direct Carbonylation of the Ortho C−H Bond in the Benzene Ring of <i>N</i>-Arylpyrazoles
The direct carbonylation of C−H bonds in the benzene ring of N-phenylpyrazoles via catalysis by ruthenium or rhodium complexes is described. The reaction of N-phenylpyrazoles with carbon monoxide and ethylene in the presence of Ru3(CO)12 or Rh4(CO)12 resulted in the site-selectivecarbonylation of the ortho C−H bonds in the benzene ring to give the corresponding ethyl ketones. A variety of functional
描述了通过钌或铑络合物催化的N-苯基吡唑苯环中CH键的直接羰基化。在Ru 3(CO)12或Rh 4(CO)12存在下,N-苯基吡唑与一氧化碳和乙烯的反应导致苯环中邻位C-H键的位点选择性羰基化,得到相应的乙基酮。苯环上的各种官能团都是可以容忍的。基于p K a,N-苯基吡唑具有比预期更高的反应性吡唑共轭酸的分子量值。用于该反应的溶剂的选择是重要的,并且N,N-二甲基乙酰胺(DMA)给出了最好的结果。