Palladium-Catalyzed Alcoholysis of 3-Iodopropynamides: Selective Synthesis of Carbamoylacetates
摘要:
A novel and selective method for the synthesis of carbamoylacetates via the alcoholysis of 3-iodopropynamides has been developed. 3-Iodopropynamides react with alcohols in the presence of palladium(II) acetate and DABCO to afford the corresponding carbamoylacetates in moderate to good yields.
A novel method for the synthesis of 2‐oxindoles from 1,3‐dicarbonyl compounds based on ferrous salt and iodide catalyst was described. Through a new catalytic oxidation system, the intramolecular dehydrogenation coupling reaction was completed by using catalytic amount of iodine.
Electrochemical dehydrogenative cyclization of 1,3-dicarbonyl compounds
作者:Zheng-Jian Wu、Shi-Rui Li、Hao Long、Hai-Chao Xu
DOI:10.1039/c8cc02472c
日期:——
The intramolecular C(sp3)–H/C(sp2)–H cross-coupling of 1,3-dicarbonyl compounds has been achieved through Cp2Fe-catalyzed electrochemical oxidation. The key to the success of these dehydrogenative cyclization reactions is the selective activation of the acidic α-C–H bond of the 1,3-dicarbonyl moiety to generate a carbon-centered radical.
benzylic position has been achieved via a 'transition-metal-free' intramolecular dehydrogenative coupling (IDC). The construction of 2-oxindole moieties was carried out through formation of carbon-carbon bonds using KOt-Bu-catalyzed one pot C-alkylation of beta-N-arylamido esters with alkyl halides followed by a dehydrogenative coupling. Experimental evidences indicated toward a radical-mediated path for
Intramolecular Dehydrogenative Coupling of sp<sup>2</sup> C–H and sp<sup>3</sup> C–H Bonds: An Expeditious Route to 2-Oxindoles
作者:Santanu Ghosh、Subhadip De、Badrinath N. Kakde、Subhajit Bhunia、Amit Adhikary、Alakesh Bisai
DOI:10.1021/ol302767w
日期:2012.12.7
An intramolecular-dehydrogenative-coupling (IDC) using "transition-metal-free" oxidation conditions has been achieved to synthesize a variety of 2-oxindoles bearing an all-carbon quaternary stereogenic center at the benzylic position. The methodology involves a one-pot C-alkylation of beta-N-arylamido esters (3, 6) with alkyl halides using potassium tert-butoxide concomitant with a dehydrogenative coupling. A radical-mediated pathway has been tentatively proposed for the oxidative process.
DDQ-mediated Direct Intramolecular-Dehydrogenative-Coupling (IDC): Expeditious Approach to the Tetracyclic Core of Ergot Alkaloids
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.