Phosphine-Mediated Divergent Cascade Cycloaddition of Cyclic Diketones and Terminal Alkynes: Access to Diverse
Yu-Lin Zhang1, Han-Han Kong1, Tian-Yu Long1
1Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, College of Materials and Chemical Engineering, China Three Gorges University, Yichang, Hubei443002, China.
Abstract:
A facile phosphine-mediated divergent cascade cycloaddition was developed to construct diverse pyran-fused polycycles from cyclic diketones and electron-deficient terminal alkynes. This reaction exhibits alkyne-tuned divergent reactivity and broad functional group compatibility, applicable to both common 2-arylidene-1,3-indanediones and rarely reported alkylidene dibenzo-β-tropolones. A plausible dual-pathway mechanism was proposed to elucidate the divergent reaction process.
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