Key Laboratory of Green Chemistry and Technology of the Ministry of Education, College of Chemistry , Sichuan University , 29 Wangjiang Road , Chengdu 610064 , P.R. China.
Org Lett. 2019 Feb 15;21(4):1152-1155. doi: 10.1021/acs.orglett.9b00099. Epub 2019 Jan 29.
Described herein is a palladium-catalyzed dearomative annulation of alkyl bromoarenes with internal alkynes. Challenges in this spiroannulation include the chemoselectivity among [2 + 2 + 1], [2 + 2 + 2], and [3 + 2] annulations and the E/ Z-selectivity associated with the generated exocyclic double bond. In the presence of Pd(OAc) and a phosphine ligand, a variety of highly functionalized spirocyclopentadienes with an exocyclic carbon-carbon double bond are provided in good to excellent yields with high chemo-, regio-, and E/ Z-selectivity via a Heck-type pathway.
本文描述了钯催化的烷基溴代芳烃与内炔烃的去芳构化环化反应。该螺环化反应中存在的挑战包括[2+2+1]、[2+2+2]和[3+2]环化之间的化学选择性以及与生成的环外双键相关的 E/Z 选择性。在 Pd(OAc) 和膦配体的存在下，通过 Heck 型途径，以良好至优异的产率、高化学选择性、区域选择性和 E/Z 选择性，提供了多种具有环外碳-碳双键的高度官能化螺环戊二烯。
