Alkynes react with organoborons under a CO atmosphere in the presence of a rhodium(I) catalyst to afford mainly 5-aryl-2(5H)-furanones, α,β-unsaturated ketones, and indanones. The product selectivity can be tuned by modifying the reaction conditions.
through the activation of its formyl C–Hbond (decarbonylation) and the latter catalyzes the subsequent dual-incorporation of the resulting carbonyl unit (carbonylation). The use of larger amounts of the phosphine-ligated rhodium(I) complex generates more carbonyl units, leading to the formation γ-butenolides via the dual-incorporation of the carbonyl unit.
Rhodium-catalyzed carbonylative arylation of alkynes with arylboronic acids: an efficient and straightforward method in the synthesis of 5-aryl-2(5H)-furanones
5-Aryl-2(5H)-furanones can be synthesized by the Rh-catalyzed reactions of arylboronic acids with internal alkynes under a CO atmosphere.
5-芳基-2(5H)-呋喃酮可以通过在CO气氛下,使用Rh催化的芳基硼酸与内炔的反应合成。
Phosphine-catalyzed activation of cyclopropenones: a versatile C<sub>3</sub> synthon for (3+2) annulations with unsaturated electrophiles
作者:Xin He、Pengchen Ma、Yuhai Tang、Jing Li、Shenyu Shen、Martin J. Lear、K. N. Houk、Silong Xu
DOI:10.1039/d2sc04092a
日期:——
α-ketenyl phosphorous ylide is validated as the key intermediate, which undergoes preferential catalytic cyclization with aldehydes rather than stoichiometric Wittig olefinations. This phosphine-catalyzed activation of cyclopropenones thus supplies a versatile C3 synthon for formal cycloadditon reactions.