4728-02-3Relevant articles and documents
SmCl3-catalyzed C-acylation of 1,3-dicarbonyl compounds and malononitrile
Shen, Quansheng,Huang, Wen,Wang, Jialiang,Zhou, Xigeng
, p. 4491 - 4494 (2008/03/12)
(Chemical Equation Presented) A recyclable, convenient, and efficient catalytic system for C-acylation of 1,3-dicarbonyl compounds and malononitrile with acid chlorides has been developed, giving moderate to excellent yields under mild conditions. This is the first catalytic example of such reactions. In addition, by applying this protocol as the key step, 3,5-disubstituted-1H- pyrazole-4-carboxylate can easily be synthesized in high yields in a one-pot procedure.
Catalytic action of azolium salts. VIII. Oxidative aroylation with arenecarbaldehydes catalyzed by 1,3-dimethylbenzimidazolium iodide
Miyashita, Akira,Suzuki, Yumiko,Nagasaki, Izuru,Ishiguro, Chie,Iwamoto, Ken-Ichi,Higashino, Takeo
, p. 1254 - 1258 (2007/10/03)
Refluxing of a mixture of benzaldehyde (1a), 1,3- dimethylbenzimidazolium iodide (7), p-nitroaniline (9b) as an oxidizing agent, and 1,8-diazabicyclo[5,4,0]-7-undecene (DBU) in MeOH afforded methyl benzoate (2a) in good yield. Other methyl arenecarboxylates 2 were similarly obtained from arenecarbaldehydes 1. We showed that this aroylation proceeds via the 2-aroyl-1,3-dimethylbenzimidazolium salt (8). The 1,2,4-triazolium salt (18) and the naphtho[1,2-d]imidazolium salt (19) were also effective catalysts for this oxidative aroylation. However, the aroylation did not proceed with the imidazolium salt (20). In the presence of flavins (25a - c), arenecarbaldehydes 1 reacted in MeOH under aerobic conditions catalyzed by the benzimidozolium salt 7 to give the corresponding methyl arenecarboxylates 2. 1-Methyl-3-[3-(10-phenylisoalloxazin-3-yl)propyl]benzimidazolium bromide (27) is an effective complex catalyst for this oxidative aroylation.