I<sub>2</sub>-Catalyzed Multicomponent Reactions for Accessing Densely Functionalized Pyrazolo[1,5-<i>a</i>]pyrimidines and Their Disulphenylated Derivatives
作者:Jun Sun、Jiang-Kai Qiu、Bo Jiang、Wen-Juan Hao、Cheng Guo、Shu-Jiang Tu
DOI:10.1021/acs.joc.6b00332
日期:2016.4.15
New I2-catalyzed multicomponent bicyclization reactions of β-ketonitriles with sulfonyl hydrazides have been established, providing a direct and metal-free access toward unreported pyrazolo[1,5-a]pyrimidin-4-ium sulfonates. The latter could be quantitatively converted into densely functionalized pyrazolo[1,5-a]pyrimidines in the presence of bases. Using sulfonyl hydrazides as a sulfenylating agent
已经建立了新的I 2催化的β-酮腈与磺酰肼的多组分双环化反应,为未报告的吡唑并[1,5 - a ]嘧啶-4-磺酸盐提供了直接且无金属的通道。后者可以在存在碱的情况下定量转化为致密的吡唑并[1,5- a ]嘧啶。使用磺酰肼作为亚磺酰化剂,得到的吡唑并[1,5- a ]嘧啶使I 2催化的空前的二苯甲基化反应通过直接的C(sp 2)-H键双官能化作用来获得完全取代的吡唑并[1,5- a ]嘧啶。