Sulfonamide-directed gold-catalyzed [2+2+2]-cycloadditions of nitriles with two discrete ynamides to construct 2,4-diaminopyridine cores
作者:Yu-Ling Chen、Pankaj Sharma、Rai-Shung Liu
DOI:10.1039/c5cc09688j
日期:——
Gold-catalyzed [2+2+2]-cycloadditions of two discrete ynamides and one one nitrile afford 2,4-diaminopyridine derivatives that are not readily prepared from typical low-valent-metal catalysts. Our mechanistic analysis reveal that the reaction chemoselectivity...
Ruthenium-Catalyzed [2 + 2] Cycloadditions of Ynamides
作者:Nicole Riddell、Karine Villeneuve、William Tam
DOI:10.1021/ol0512841
日期:2005.8.1
[GRAPHICS]Ruthenium-catalyzed [2 + 2] cycloadditions between norbornene and ynamides were investigated. The ynamide moiety was found to be compatible with the ruthenium-catalyzed cycloaddition conditions, giving the corresponding cyclobutene cycloadducts in moderate to good yields (up to 97%).
Ruthenium-catalyzed [2+2] cycloadditions of bicyclic alkenes and ynamides
作者:Karine Villeneuve、Nicole Riddell、William Tam
DOI:10.1016/j.tet.2005.11.081
日期:2006.4
Ruthenium-catalyzed [2+2] cycloadditionsbetweenbicyclicalkenes and ynamides were investigated. The ynamide moiety was found to be compatible with the ruthenium-catalyzedcycloaddition conditions giving the corresponding cyclobutene cycloadducts in moderate to good yields (up to 97%). Diastereoselective cycloaddition utilizing chiral cyclic ynamides were also examined and a low to moderate level
with a catalytic amount of TpRuCl(PPh3)2 resulted in the construction of indole scaffolds known as privileged structure motifs. This reaction involved a cascade of 1,2‐rearrangement and cyclization carrying out C−C bond formationvia a rutheniumvinylidene intermediate, as revealed by a deuterium‐labeling experiments. Furthermore, the transformation of multi‐functionalized ynamide, derived from a practical