Gold-catalyzed reactions of propargylic esters with vinylazides for the synthesis of Z- or E-configured buta-1,3-dien-2-yl esters
作者:Sachin Bhausaheb Wagh、Rai-Shung Liu
DOI:10.1039/c5cc05945c
日期:——
Gold-catalyzed synthesis of buta-1,3-dien-2-yl esters by the reaction of propargyl esters with vinylazides is described; the reaction mechanism is postulated to involve a vinyl attack of vinylazides at alkenyl gold carbenes.
Gold(I) catalysed cycloisomerisation of β-hydroxy propargylic esters to dihydropyrans/2H-pyrans via allene intermediates
作者:Ramesh Kotikalapudi、K.C. Kumara Swamy
DOI:10.1016/j.tet.2013.07.003
日期:2013.9
Efficient cycloisomerisation of β-hydroxy propargylic esters to dihydropyrans/2H-pyrans via 1,3-carboxylate migration followed by regioselective hydroxyl addition to the transient allene intermediate catalysed by Ph3PAuCl/AgSbF6 is presented. Similar reactions on phosphorylated precursors led to phosphono-furans and phosphono-pyrans. In a few cases, self-condensation of β-hydroxy propargylic esters
Azepine Synthesis from Alkyl Azide and Propargylic Ester via Gold Catalysis
作者:Heng Liu、Xin Li、Zili Chen、Wen-Xiang Hu
DOI:10.1021/jo300667a
日期:2012.6.1
multisubstituted 4, 5-dihydro-1H-azepine derivatives through the gold-catalyzed reaction of two molecules of propargylic esters with one molecule of alkyl azide. It was proposed that vinyl gold carbenoid, in situ generated from propargylic ester through gold-catalyzed 1, 2-rearrangement, was trapped by alkyl azide to give vinyl imine intermediate. These, in turn, could undergo a formal [4 + 3] cycloaddition with
通过金催化两分子炔丙酸酯与一分子烷基叠氮化物的金催化反应,开发了一种有效的新方法来合成多取代的4、5-二氢-1 H - ze庚因衍生物。有人提出,用烷基叠氮化物捕获炔丙基酯通过金催化的1、2-重排原位生成的乙烯基金类胡萝卜素,得到乙烯基亚胺中间体。这些反过来可能会与另一分子乙烯基金类胡萝卜素进行正式的[4 + 3]环加成反应,从而提供所需的氮杂产物。
NHC–gold(<scp>i</scp>) catalysed [4 + 2] cycloaddition–acyclic addition of dialkyl substituted propargylic esters with 1,3-diphenylisobenzofuran: synthesis of novel benzo[c]fluorenols and substituted dienes
作者:Ramesh Kotikalapudi、A. Leela Siva Kumari、K. C. Kumara Swamy
DOI:10.1039/c4ra01105h
日期:——
A gold carbene complex [IPrAuCl/AgSbF6] catalysed novel cycloaddition of propargylic esters with 1,3-diphenylisobenzofuran is reported. A [4 + 2] cycloaddition followed by sequential aromatic allylation leading to pentannulation with the expulsion of benzoic acid, then 1,2-phenyl migration coupled with ring opening and aromatisation leading to a new class of benzofluorenols, is discovered. This process
Lewis Basicity of Water for a Selective Monodehalogenation of α,α-Dihalo Ketones to α-Halo Ketones and Mechanistic Study
作者:Santu Sadhukhan、Beeraiah Baire
DOI:10.1002/adsc.201701233
日期:2018.1.17
Utilizing this concept, a new strategy for the highly controlled and selective mono‐dehalogenation of α,α‐dihalo ketones has been discovered and is reported in this contribution. Extending this concept, the first direct conversion of propargylic acetates to the corresponding α‐iodo ketones via α,α‐dihalo ketones has also been efficiently achieved under metal‐free conditions. During the latter process