Cu(II)-catalyzed highly enantioselective intramolecular cyclization of N-alkenylureas was developed for the concise assembly of chiral vicinal diamino bicyclic heterocycles. Facile removal of carbonyl group of the carbamido moiety allowed for ready access to enantioenriched cyclic vicinal diamines.
Propylphosphonic Anhydride (T3P®): A Remarkably Efficient Reagent for the One-Pot Transformation of Aromatic, Heteroaromatic, and Aliphatic Aldehydes to Nitriles
Propylphosphonic anhydride has been demonstrated to be an efficient reagent for the transformation of aromatic, heteroaromatic, and aliphatic aldehydes to respective nitriles in excellent yields. This procedure offers simple and one-pot access to nitriles and highlights the synthetic utility of T3P® as a versatile reagent in organic chemistry.
Copper-Catalyzed Carbonylative Synthesis of β-Homoprolines from <i>N</i>-Fluoro-sulfonamides
作者:Youcan Zhang、Zhiping Yin、Xiao-Feng Wu
DOI:10.1021/acs.orglett.0c00227
日期:2020.3.6
A new methodology for the carbonylative transformation of N-fluoro-sulfonamides into N-sulfonyl-β-homoproline esters has been described. In the presence of a catalytic amount of Cu(OTf)2, a range of β-homoproline derivatives were prepared in moderate to good yield. The reaction proceeds via the intramolecular cyclization and intermolecular carbonylation of a free carbon radical. Notably, this procedure
Palladium(II)-Catalyzed Intramolecular Diamination of Unfunctionalized Alkenes
作者:Jan Streuff、Claas H. Hövelmann、Martin Nieger、Kilian Muñiz
DOI:10.1021/ja055190y
日期:2005.10.1
Intramolecular diamination reactions are described which yield cyclic ureas as direct products of an oxidative alkene transformation in the presence of palladium acetate and iodosobenzenediacetate as terminal oxidant. The reaction is truly catalytic in metal catalyst and represents the proof of principle for this elusive type of alkene oxidation.
Palladium-Catalyzed Aerobic Oxidative Cyclization of Aliphatic Alkenyl Amides for the Construction of Pyrrolizidine and Indolizidine Derivatives
作者:Dan Yang、Kai-Yip Lo、Liu Ye
DOI:10.1055/s-0036-1588502
日期:2017.8
An efficient palladium-catalyzed aerobic oxidative cyclization has been developed to synthesize a variety of pyrrolizidine and indolizidine derivatives from simple aliphatic alkenyl amides in moderate to good yields. The reaction features the capability of accessing various N-heterocycles and the use of molecular oxygen (1 atm) as the green oxidant.