Divergent Domino Reactions of Prop-2-ynylsulfonium
Salts: Access to Sulfur-Containing Benzo-Fused Dioxabicyclo[3.3.1]nonanes
and Dihydrofuro[2,3‑c]chromenes
posted on 2020-07-29, 18:09authored byYiming Zhou, Yu Chen, You Huang
Solvent-controlled divergent domino
annulation reactions between
2-hydroxy-2-methylchromene derivatives and prop-2-ynylsulfonium salts
have been developed. Specifically, a sequential [4 + 2] and [4 + 2]
annulation reaction occurred in 1,2-dichloroethane affording sulfur-containing
benzo-fused dioxabicyclo[3.3.1]nonanes. In contrast, by changing the
solvent to toluene, the reaction course switched to a [4 + 2] and
[4 + 1] annulation reaction to afford dihydrofuro[2,3-c]chromenes. It is noteworthy that the prop-2-ynylsulfonium salt participates
in the transformation with its γ-carbon atom for the first time.