Unexpected regio- and chemoselectivity of cationic gold-catalyzed cycloisomerizations of propargylureas: access to tetrasubstituted 3,4-dihydropyrimidin-2(1H)-ones
Synthesis of Imidazolidin-2-ones and Imidazol-2-ones via Base-Catalyzed Intramolecular Hydroamidation of Propargylic Ureas under Ambient Conditions
作者:Alessandra Casnati、Antonio Perrone、Paolo P. Mazzeo、Alessia Bacchi、Raffaella Mancuso、Bartolo Gabriele、Raimondo Maggi、Giovanni Maestri、Elena Motti、András Stirling、Nicola Della Ca’
DOI:10.1021/acs.joc.9b00064
日期:2019.3.15
The first organo-catalyzed synthesis of imidazolidin-2-ones and imidazol-2-ones via intramolecular hydroamidation of propargylic ureas is reported. The phosphazene base BEMP turned out to be the most active organo-catalyst compared with guanidine and amidine bases. Excellent chemo- and regioselectivities to five-membered cyclic ureas have been achieved under ambient conditions, with a wide substrate
Copper/DTBP-Promoted Oxyselenation of Propargylic Amines with Diselenides and CO<sub>2</sub>: Synthesis of Selenyl 2-Oxazolidinones
作者:Jia-Min Chen、Lin Qi、Linlin Zhang、Li-Jun Li、Cong-Ying Hou、Wei Li、Li-Jing Wang
DOI:10.1021/acs.joc.0c01519
日期:2020.8.21
A highly efficient electrophilic oxyselenation of propargylic amines with diselenides and CO2 under atmospheric pressure promoted by copper/DTBP is reported. Various biologically important selenyl 2-oxazolidinones were produced in moderate to excellent yields. The developed method features a broad substrate scope, easy scalability, and mild reaction conditions.
Efficient Microwave-Assisted Synthesis of Secondary Alkylpropargylamines by Using A<sup>3</sup>-Coupling with Primary Aliphatic Amines
作者:Jitender B. Bariwal、Denis S. Ermolat'ev、Erik V. Van der Eycken
DOI:10.1002/chem.200903143
日期:2010.3.15
Three‐component coupling reaction: An efficient, microwave‐assisted, CuI‐catalysed A3‐coupling reaction with primaryaliphaticamines that gives access to secondary propargylamines is described (see scheme).
Cationic Gold- and Silver-Catalyzed Cycloisomerizations of Propargylic Ureas: A Selective Entry to Oxazolidin-2-imines and Imidazolidin-2-ones
作者:Olga P. Pereshivko、Vsevolod A. Peshkov、Jeroen Jacobs、Luc Van Meervelt、Erik V. Van der Eycken
DOI:10.1002/adsc.201200905
日期:2013.3.11
gold(I) catalysis generally resulted in a formation of oxazolidin‐2‐imines as major products while the application of silver(I) triflate selectively provided the corresponding imidazolidin‐2‐ones. An attempt to rationalize the observed chemoselectivity is described. The scope of both processes was demonstrated through the use of variously substituted secondary propargylic amines.