Addition of Allylindium Bromide to Nitrile Oxides in Aqueous Media: Convenient Synthesis of 5-Methylisoxazolines
作者:Sanghapal D. Sawant、Parvinder P. Singh、Naveed A. Qazi、H. M. Sampath Kumar
DOI:10.1246/cl.2007.296
日期:2007.2
5-Methylisoxazolines were obtained in good yields through a highly selective nucleophilic addition of allylindium reagent to benzonitrile oxides with concominant C-O heterocyclization.
通过将烯丙基试剂高度选择性地亲核加成到氧化苄腈并伴随 CO 杂环化,以良好的收率获得了 5-甲基异恶唑啉。
Reaction of allenylmagnesium and allenylindium bromides with nitrile oxides: synthesis of novel 5-butynyl- and 5-methylisoxazoles
obtained in high yields through a domino addition, C–O heterocyclization involving allenylmagnesium bromide and benzonitrile oxide in dry THF, in which the corresponding 5-methylisoxazoles were isolated in trace amounts. However, when the reactions were attempted in aqueous media using allenylindium bromide, 5-methylisoxazoles were formed as the sole products in high yields.
An organo-NHC catalyzed domino addition approach for the selective synthesis of 5-butynylisoxazoles and subsequent Sonogashira coupling
作者:Shravankumar Kankala、Sreekantha B. Jonnalagadda、Chandra Sekhar Vasam
DOI:10.1039/c5ra11947b
日期:——
A nucleophilic organo N-heterocyclic carbene (NHC) catalysed click-type fast dominoaddition of allenyl-MgBr to aryl nitrile oxides to produce 5-butynylisoxazoles with excellent selectivity and good yields is reported. The unwanted protonation and subsequent formation of 5-methylisoxazole byproducts is successfully suppressed. Furthermore, a Pd/Ag catalysed protocol for Sonogashira cross-coupling of