Tandem enyne allene-radical cyclization via base-catalyzed isomerization of enediyne sulfones
作者:Janet Wisniewski Grissom、Detlef Klingberg
DOI:10.1016/00404-0399(50)1366-p
日期:1995.9
Enediyne sulfones 12–16 undergo a base-catalyzedisomerization to the corresponding enyne allenes followed by a tandem enyne allene-radical cyclization at 37 °C to provide 2,3-dihydrobenz[e]indenes 17–21 in good yields.
烯炔砜12-16经过碱催化异构化为相应的烯炔丙二烯,然后在37°C下串联烯炔丙烯-自由基环化,以高收率提供2,3-二氢苯并[ e ]茚17-21。
Experimental and Computational Evidence for Gold Vinylidenes: Generation from Terminal Alkynes via a Bifurcation Pathway and Facile C–H Insertions
作者:Longwu Ye、Yanzhao Wang、Donald H. Aue、Liming Zhang
DOI:10.1021/ja2091992
日期:2012.1.11
species is highly reactive and undergoes facile intramolecular C(sp(3))-H insertions as well as O-H and N-H insertions. The formation step for the gold vinylidene is predicted theoretically to be complex with a bifurcated reaction pathway. A pyridine N-oxide acts as a weak base to facilitate the formation of an alkynylgold intermediate, and the bulky BrettPhos ligand in the gold catalyst likely plays a
Gold‐Catalyzed Intermolecular Oxidative Diyne Cyclizations via 1,6‐Carbene Transfer
作者:Qian Wang、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/adsc.201901318
日期:2020.2.21
A vinyl/α‐oxo carbene is generated via an α‐oxo carbene formation and subsequently transferred across the second alkyne. These highly active species can react with nitriles in an intermolecular fashion to provide substituted oxazoles. This methodology goes through 1,6‐carbene shift and offers a range of valuable products.
Synthesis of tetracyclic chromenones via platinum(ii) chloride catalysed cascade cyclization of enediyne–enones
作者:Mahalingam Sivaraman、Paramasivan T. Perumal
DOI:10.1039/c3ob41911h
日期:——
PtCl2 catalysed cascade cyclization of an enediyneâenone system to afford a tetracyclic chromenone is reported, which proceeds through two consecutive highly regioselective 6-endoâdig cyclizations in a single step with the formation of two new CâC bonds and two new rings in excellent yield. A mechanism for this transformation is proposed based on the isolated intermediates.
作者:Pascal Nösel、Tobias Lauterbach、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/chem.201300507
日期:2013.6.24
We report the gold‐catalyzed synthesis of highly functionalized iodofulvenes from iododialkynes under mild conditions. The catalytic cycle involves the formation of gold acetylides and vinylgold intermediates. These intermediates can then undergo an unprecedented iodine/gold exchange. This new pathway for catalyst transfer in dual gold catalysis opens up the possibility of highly regioselective transformations