The application of a C(vinyl), C(aryl)-palladacycle from vinyl-containing substrates is challenging due to the interference of a reactive double bond in palladium catalysis. This Letter describes a [4 + 2] or [4 + 3] cyclization based on a C(vinyl), C(aryl)-palladacycle by employing α-oxocarboxylic acids as the insertion units under a palladium/air system. The reaction proceeded through the key vinyl
Colonge; Arsac, Bulletin de la Societe Chimique de France, 1954, p. 445,446
作者:Colonge、Arsac
DOI:——
日期:——
Preparative supercritical deuterium exchange in arenes and heteroarenes
作者:Thomas Junk、W.James Catallo
DOI:10.1016/0040-4039(96)00615-6
日期:1996.5
Deuterated homo- and heterocyclic aromatic substrates bearing various functionalities were prepared by isotope exchange in supercriticaldeuterium oxide, with little or no formation of byproducts. Equilibration was attained rapidly (1 – 24 hrs), and deuteriumexchange extended to alpha positions of alkyl homologs. Nitro- and haloarenes, thioethers, telluroethers, and some heterocyclic substrates were
achievements of catalytic carbonyl–olefin metathesis (CCOM) mediated by Lewis acid catalysts, exploration of the CCOM through Brønsted acid-catalyzed approaches remains quite challenging. Herein, we disclose a synthetic protocol for the construction of a valuable polycycle scaffold through the CCOM with the inexpensive, nontoxic phosphomolybdic acid as a catalyst. The current annulations could realize carbonyl–olefin