Cu(I)-Catalyzed Synthesis of Dihydropyrimidin-4-ones toward the Preparation of β- and β<sup>3</sup>-Amino Acid Analogues
作者:Basker Rajagopal、Ying-Yu Chen、Chun-Chi Chen、Xuan-Yu Liu、Huei-Ren Wang、Po-Chiao Lin
DOI:10.1021/jo402670d
日期:2014.2.7
A copper(I)-catalyzed synthesis of substituted dihydropyrimidin-4-ones from propargyl amides via the formation of ketenimine intermediate has been successfully developed; the synthesis afforded good isolated yields (80–95%). The mild reaction conditions at room temperature allow the reaction to proceed to completion in a few hours without altering the stereochemistry. Further, by involving a variety
Silver-Catalyzed Cyclization of Propargylic Amides to Oxazolines
作者:Valerie H. L. Wong、Andrew J. P. White、T. S. Andy Hor、King Kuok Mimi Hii
DOI:10.1002/adsc.201500610
日期:2015.12.14
is observed in the cyclization of propargylicamides catalyzed by bis(pyridyl)silver(I) complexes, with an unexpected reversal of electronic demand to the analogous NH addition reaction. The catalyst was found to be effective for internal alkyne substrates, offering exclusive selectivity for the 5-exo-dig product. Differences in selectivity profile between gold- and silver-catalyzed processes are highlighted
A palladium-catalyzed process to construct oxazoles and oxazolines with broad functional-group tolerance has been developed, and the method introduces difluoromethyl groups into heterocycles in a one-pot fashion. This system uses a carbonyl oxygen as the acceptor for the addition of a vinylpalladium intermediate to achieve the cyclization. Oxazoline derivatives are generated as the Z-isomer with high
Synthesis, Structure and Catalytic Activity of NHC-Ag<sup>I</sup>
Carboxylate Complexes
作者:Valerie H. L. Wong、Sai V. C. Vummaleti、Luigi Cavallo、Andrew J. P. White、Steven P. Nolan、King Kuok Mimi Hii
DOI:10.1002/chem.201601762
日期:2016.9.5
A general synthetic route was used to prepare 15 new N‐heterocyclic carbene (NHC)–AgI complexes bearing anionic carboxylate ligands [Ag(NHC)(O2CR)], including a homologous series of complexes of sterically flexible ITent ligands, which permit a systematic spectroscopic and theoretical study of the structural and electronic features of these compounds. The complexes displayed a significant ligand‐accelerated
Iodine-promoted cyclization of N-propynyl amides and N-allyl amides via sulfonylation and sulfenylation
作者:Gopal Chandru Senadi、Bing-Chun Guo、Wan-Ping Hu、Jeh-Jeng Wang
DOI:10.1039/c6cc05138c
日期:——
Iodine-promoted sulfonylation of N-propynyl amides with sulfonyl hydrazides followed by DBU mediated cyclisation to afford 5-methyl-arylsulfonyloxazoles and oxysulfenylation of N-allyl amides through electrophilic addition of in situ generated sulfenyl iodide...