W(CO)5(L)-Catalyzed Cyclization of α-Alkynyl-β-dicarbonyl Derivatives: Synthesis of Methylenelactones, Furans, and Methylenecyclopentanes
作者:Sunggak Kim、Xiangjian Meng
DOI:10.1055/s-0032-1316536
日期:2012.8
W(CO)(5)(L)-Catalyzed cyclization of alpha-alkynyl-beta-keto acids, keto esters, and diketones provides methylenelactones, furans, and methylenecyclopentanes via 5-exo-dig cyclization. Also, the present approach can be further applied to 5-endo-dig cyclization.
Ruthenium-Catalyzed Cycloisomerizations of Diynols
作者:Barry M. Trost、Michael T. Rudd
DOI:10.1021/ja043097o
日期:2005.4.1
[CpRu(CH(3)CN)(3)]PF(6). The formation of five- and six-memberedrings is possible using this methodology. Secondary diynols react to form single geometrical isomeric dienones and -als. Primary diynols undergo a cycloisomerization as well as a hydrative cyclization process. The utility of primary diynol cycloisomerization is demonstrated in a synthesis of (+)-alpha-kainic acid.