A new method to generate a series of spiro-pyrazolone-tetrahydrofurans/pyrans is developed by using a base-mediated cascade ipso-cyclization of unsaturated pyrazolones and haloalcohols. Noteworthy aspects of this methodology include its brief reaction duration, expansive substrate applicability, very good yields, and mild reaction conditions without the need for transition metals. Interestingly, the
通过使用不饱和
吡唑啉酮和卤代醇的碱介导级联原位环化,开发了一种生成一系列螺
吡唑啉酮-
四氢呋喃/
吡喃的新方法。该方法值得注意的方面包括其短暂的反应时间、广泛的底物适用性、非常好的收率以及不需要过渡
金属的温和反应条件。有趣的是,本策略的实际可行性也在克级范围内进行了研究,提供了良好的产品收率。