DDQ-mediated Direct Intramolecular-Dehydrogenative-Coupling (IDC): Expeditious Approach to the Tetracyclic Core of Ergot Alkaloids

作者：Bhunia Subhajit; Ghosh Santanu; Dey Dhananjay; Bisai Alakesh^*

来源：Organic Letters, 2013, 15(10): 2426-2429.

DOI：10.1021/ol400899e

An efficient route to 2-oxindoles bearing an all-carbon quaternary center at the pseudobenzylic position has been developed via a DDQ-mediated Intramolecular-Dehydrogenative-Coupling (IDC). The methodology involves a one-pot C-alkylation of beta-N-arylamido esters (7) concomitant with dehydrogenative-coupling in the presence of stoichiometric amount of DDQ. A tentative mechanistic route has been proposed for the oxidative coupling. The methodology provides a two-step entry to the ergoline structure of ergot alkaloids.

• 出版日期2013-5-17