Modified Julia Olefination on Anhydrides: Extension and Limitations. Application to the Synthesis of Maculalactone B
作者:Nicolas Dussart、Huu Vinh Trinh、David Gueyrard
DOI:10.1021/acs.orglett.6b02160
日期:2016.10.7
esters from cyclic anhydrides is reported using a modifiedJuliaolefination. The reaction is highly stereoselective. The Smiles rearrangement can be performed in a one-pot process, giving a straightforward access to exo-enol lactones. Furthermore, the reaction was extended to semistabilized sulfones, and this methodology was applied to the synthesis of maculalactone B.
Wittig-Horner Reaction of Dimethyl Phthalide-3-phosphonates with Ketones: Synthesis of 3-Ylidenephthalides and Their Conversion to 2,2-Disubstituted Indan-1,3-diones Including Spirocyclic Compounds
The Wittig-Horner reaction of dimethyl phthalide-3-phosphonates with various ketones was investigated under the conditions: lithium bis(trimethylsilyl)amide (LHMDS) or sodium hydride in tetrahydrofuran, and cesium carbonate in isopropyl alcohol. The sequential treatment of the 3-ylidenephthalides with diisobutylaluminium hydride (DIBAL-H) and pyridinium dichromate (PDC) afforded 2,2-disubstituted indan-1,3-dione derivatives in modest to high overall yields.