A nickel(0) catalyzed cycloaddition of alkynes and isocyanates that affords pyrimidine-diones
作者:Hung A. Duong、Janis Louie
DOI:10.1016/j.tet.2006.03.119
日期:2006.8
carbene catalyzedcycloaddition of one alkyne and two isocyanates that affords pyrimidine-dione is described. The key to the success of this protocol is the use of unsymmetrically substituted alkynes that favors the formation of pyrimidine-diones over pyridones. A variety of pyrimidine-diones were prepared. A one-pot cycloaddition and Stille coupling were reported for tributyl(1-propynyl)tin. Competition
Nickel-Catalyzed Cycloaddition of Alkynes and Isocyanates
作者:Hung A. Duong、Michael J. Cross、Janis Louie
DOI:10.1021/ja046477i
日期:2004.9.1
A mild and general route for preparing 2-pyridones from isocyanates and diynes is described. Ni imidazolyidene complexes were used to mediate cyclizations between both internal and terminal diynes with aryl and alkyl isocyanates. In addition, the efficacy of this protocol allows for the preparation of a fused seven-membered pyridone and for three component cyclizations.
Nickel(0)-katalysierte [2+2+2′]-Cycloaddition von Alkynen mit Isocyanaten zu 2-Oxo-1,2-dihydropyridinen
作者:Heinz Hoberg、Benno W. Oster
DOI:10.1055/s-1982-29800
日期:——
HOBERG, H.;OSTER, B. W., SYNTHESIS, BRD, 1982, N 4, 324-325
作者:HOBERG, H.、OSTER, B. W.
DOI:——
日期:——
Selective synthesis of 2-pyridones and pyrimidine-2,4-diones by neutral rhodium(I) complex-catalyzed cyclocotrimerization of alkynes and isocyanates
A neutral rhodium(I) complex, ‘RhCl(PPh3)2’ generated by the combination of [RhCl(C2H4)2]2 with a fourfold amount of PPh3, effectively catalyzed the cyclocotrimerization of alkynes (1) and isocyanates (2) to give 2-pyridones (3) and/or pyrimidine-2,4-diones (4), selectively, by controlling the molar ratio of alkynes (1) and isocyanates (2).
由[RhCl(C 2 H 4)2 ] 2与四倍量的PPh 3结合生成的中性铑(I)络合物'RhCl(PPh 3)2 '有效催化了炔烃(1)和异氰酸酯(2),通过控制炔烃(1)和异氰酸酯(2)的摩尔比,有选择地生成2-吡啶酮(3)和/或嘧啶-2,4-二酮(4)。