A strategy for the synthesis of spiroketal compounds through a tandem iodocyclization of 1-(2-ethynylphenyl)-4-hydroxybut-2-yn-1-one derivatives is presented. This reaction could proceed under very mild conditions in a short time and avoid the use of expensive and toxic metal catalysts. Moreover, the resulting halides can be further exploited by subsequent palladium-catalyzed coupling reactions, which
Molybdenum(0)-Promoted Carbonylative Cyclization of<i>o</i>-Haloaryl- and β-Haloalkenylimine Derivatives by Oxidative Addition of a Carbon(sp<sup>2</sup>)Halogen Bond: Preparation of Two Types of γ-Lactams
作者:Jun Takaya、Kenichiro Sangu、Nobuharu Iwasawa
DOI:10.1002/anie.200902884
日期:2009.9.7
Lovely lactams: Synthetically useful γ‐lactam derivatives have been prepared through the unique title transformation. By utilizing the characteristic property of the molybdenum complex, two kinds of products (both of which have rarely been obtained by reactions catalyzed by late transition metals) were obtained selectively by adjusting the reaction conditions (see scheme).
of 1-(trifluoromethyl)-1H-indenes. The success of this strategy hinges upon a well-balanced process for the generation of two transient reactive species, specifically trifluoroethylsilver and alkenylpalladium intermediates, in the same molecule, as well as a smooth transmetalation step, which delicately joins together these two different metallic intermediates.
Novel Platinum-Catalyzed Tandem Reaction: An Efficient Approach to Construct Naphtho[1,2-<i>b</i>]furan
作者:Hao Wei、Hongbin Zhai、Peng-Fei Xu
DOI:10.1021/jo802645s
日期:2009.3.6
An efficient approach to synthesize naphtho[1,2-b]furan has been developed via platinum-catalyzedtandem reaction. This new tandem catalysis induces a cycloisomerization of allenyl ketone, followed by a 6π-electrocyclization-type reaction of carbene intermediate. The metal carbene proved to be an effective intermediate in the 6π-electrocyclization-type reaction.
通过铂催化串联反应,已经开发了一种合成萘并[1,2- b ]呋喃的有效方法。这种新的串联催化作用引起烯丙基酮的环异构化,然后进行卡宾中间体的6π-电环化型反应。金属卡宾被证明是6π-电环化型反应的有效中间体。
Platinum-Catalyzed Cyclization of o-Alkynyl(oxo)benzenes with Alkenes by 1,2-Migration of Benzene: Synthesis of 8-Oxabicyclo[3.2.1]octane Derivatives
An interesting migration of the rigid structure of benzene was observed when propargylic esters were introduced to the cyclization chemistry of o-alkynyl(oxo)benzene. Various 8-oxabicyclo[3,2,1]octanederivatives with many functional groups could be synthesized from this efficient approach catalyzed by platinum. The high stereo- and regioselectivity involved in this transformation was also attractive