A carboxyl-assisted C–H functionalization of acrylic acids with formaldehyde to give butenolides is described. It is the first time that the addition of an inert vinylic C–H bond to formaldehyde has been achieved via cobalt-catalyzed C–H activation. The unique reactivity of the cobalt species was observed when compared with related Rh or Ir catalysts. γ-Hydroxymethylated butenolides were produced by
描述了用甲醛对丙烯酸进行羧基辅助的 C-H 官能化以得到丁烯内酯。这是首次通过钴催化的 C-H 活化将惰性乙烯基 C-H 键添加到甲醛中。与相关的 Rh 或 Ir 催化剂相比,观察到钴物种的独特反应性。γ-羟甲基化丁烯内酯是通过Na 2 CO 3在一锅催化反应后处理制备的。
Palladium-Catalyzed Asymmetric Allylic Alkylation of Cyclic Dienol Carbonates: Efficient Route to Enantioenriched γ-Butenolides Bearing an All-Carbon α-Quaternary Stereogenic Center
Allyl dienol carbonates (1) served as substrates for the title reaction to afford the furanones 2 in both high yields and high enantioselectivities. These furanones were eventually converted into valuable buildingblocks including γ‐tertiary and γ‐quaternary furanones (3) as well as β‐quaternary butyrolactones (4). This method was used as a key step in the totalsynthesis of (−)‐nephrosteranic acid