Yb(OTf)3‑Mediated Access to Furans from β‑Ketothioamides via Eschenmoser Sulfide Contraction Reaction

A mild and straightforward synthetic
protocol for construction
of a furan skeleton promoted by Yb­(OTf)3 from β-ketothioamides
and arylglyoxals has been developed at room temperature. Importantly,
this protocol involves a tandem sequence that includes aldol condensation,
N-cyclization, ring opening, O-cyclization, S-cyclization, and Eschenmoser
sulfide contraction.

在室温条件下，已成功开发出一种温和且简便的合成协议，该协议由Yb-（OTf）3催化，从β-酮硫酰胺和芳基甘露醛中构建呋喃骨架。值得注意的是，该协议包含一系列串联反应，包括醛缩合、N-环化、环开环、氧环化、硫环化和埃申莫瑟硫缩合。