Highly Regioselective [3 + 2] Annulation of Azomethine Imines with 1-Alkynyl Fischer Carbene Complexes to Functionalized <i>N</i>,<i>N</i>-Bicyclic Pyrazolidin-3-ones
作者:Ning Luo、Zhaoyan Zheng、Zhengkun Yu
DOI:10.1021/ol201139w
日期:2011.7.1
The highly regioselective [3 + 2] cycloaddition of azomethine imines to 1-alkynyl Fischer carbene complexes has been successfully realized under mild conditions. Oxidative demetalation of the newly formed pyrazolo-pyrazolone carbene complexes with pyridine-N-oxide or ceric ammonium nitrate efficiently afforded pyrazolo-pyrazolone derivatives as well as cycloprop-2-enone and trisubstituted 1H-pyrazoles
在温和条件下,已成功实现了对亚甲亚胺亚胺的高度区域选择性[3 + 2]环加成反应生成1-炔基菲舍尔卡宾配合物。将新形成的吡唑并吡唑酮卡宾配合物与吡啶-N-氧化物或硝酸铈铵进行氧化脱金属,可以有效地提供吡唑并吡唑酮衍生物以及环丙-2-烯酮和三取代的1 H-吡唑,为制备新的途径提供了一条新颖的途径。通用的官能化的N,N-双环吡唑烷基-3-酮。