Alexy Eric J, Fulton Tyler J, Zhang Haiming, Stoltz Brian M
Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering , Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , CA 91125 , USA . Email:
Small Molecule Process Chemistry, Genentech, Inc. , 1 DNA Way , South San Francisco , CA 94080 , USA . Email:
Chem Sci. 2019 May 17;10(23):5996-6000. doi: 10.1039/c9sc01726g. eCollection 2019 Jun 21.
The first enantioselective palladium-catalyzed decarboxylative allylic alkylation of fully substituted -acyl indole-derived enol carbonates forming acyclic all-carbon quaternary stereocenters is reported. Excellent yields up to 99% and enantioselectivities up to 98% ee are obtained through the use of a new electron-deficient phosphinoxazoline (PHOX) ligand. Control of substrate enolate geometry is crucial for high selectivity. The obtained α-quaternary -acyl indoles are formal ester equivalents, and represent a useful handle for further synthetic transformations.
报道了首例钯催化的全取代β-酰基吲哚衍生的烯醇碳酸酯的对映选择性脱羧烯丙基烷基化反应，该反应可形成无环全碳季碳立体中心。通过使用一种新型缺电子磷杂恶唑啉（PHOX）配体，可获得高达99%的优异产率和高达98% ee的对映选择性。控制底物烯醇盐的几何结构对于高选择性至关重要。所得到的α-季碳β-酰基吲哚是形式上的酯等价物，并且是进一步合成转化的有用中间体。
