In situ intramolecular catalytic 1,2-addition of allenoates to cyclic ketones towards polycyclic allenoates
作者:Clément F. Heinrich、Michel Miesch、Laurence Miesch
DOI:10.1039/c4ob02451f
日期:——
Sequential deprotonation, isomerization of 3-alkynoates and subsequent 1,2-addition led to bicyclic allenoate in the presence of a catalytic amount of Cs2CO3. Cyclization proceeds in a totally stereoselective manner in the case of the two-carbon linker chain. A one-pot reaction starting from alkynyl ketones afforded tricyclic fused ring systems with good yields.
在催化量的Cs 2 CO 3存在下,连续的去质子化,3-链烷酸酯的异构化以及随后的1,2-加成导致双环烯丙酸酯。在二碳连接子链的情况下,环化以完全立体选择性的方式进行。从炔基酮开始的一锅反应得到具有良好收率的三环稠合环系统。
Thiophenol-Mediated 1,5-Hydrogen Atom Abstraction: Easy Access to Mono- and Bicyclic Compounds
method for cyclization of alkynes is described. The reaction cascade involves the intermolecular addition of a phenylthiyl radical to a terminal triple bond generating an alkenylradical, followed by a 1,5-hydrogen atom transfer and a 5-exo-trig radicalcyclization. This very efficient tin-free procedure allows one to prepare highly functionalized cyclopentane derivatives as well as fused bicyclic and
Sequential radical cyclization, alkoxy-radical fragmentation, and recyclization processes: a novel method for the synthesis of fused cycloheptanones and cyclooctenones from cyclohexanones
Preparation de composes bicycliques et d'heterocyclesazote ou oxygene bicycliques possedant une fonction cetone, enone ou alcool, a partir de cetones acetyleniques
制备 de composes bicycliques et d'heterocycles azote ouoxye bicycliques possedant une fonction cetone, enone ou alcool, a partir de cetones acetyleniques
Gold-catalysed room-temperature cycloisomerisation of alkynes and unactivated enolisable ketones
作者:Paul W. Davies、Christelle Detty-Mambo
DOI:10.1039/c003473h
日期:——
The cycloisomerisation of simple keto-alkynes proceeds at room temperature under the mild conditions of gold catalysis. Bicyclic fused and spiro compounds can be obtained by overall 5-exo and 6-exo carbon–carbon bond-forming cyclisations.