Faculty of Pharmaceutical Sciences, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510, Japan.
Angew Chem Int Ed Engl. 2013 Jul 22;52(30):7845-9. doi: 10.1002/anie.201303684. Epub 2013 Jun 20.
Palladium and CO: Carbonylation of 1 with [Pd(tfa)2(±)-L1] (tfa = trifluoroacetate) affords the spirofuranone 2 with inversion of the stereochemistry at C17 in 96 % yield. C17-epi-1 also gave the same product 2 with retention of the stereochemistry at C17. Labelling studies show that (13)CO was incorporated into the C5' position of the furanone ring. The first asymmetric version of this new reaction was achieved.
[Pd(tfa)2(±)-L1]（tfa = 三氟乙酸盐）与 1 反应进行羰基化反应，以 96%的收率得到 C17 立体化学发生反转的螺环呋喃酮 2。C17-epi-1 也以 C17 立体化学保留的方式得到相同的产物 2。标记研究表明 (13)CO 掺入到呋喃酮环的 C5' 位。首次实现了这种新反应的不对称版本。
