An Unusual Conversion of 2‐(Alkynonyl)Alkynylbenzenes to Isocoumarins by a Retro‐Favorskii‐like Degradation
作者:Jampani Santhi、Beeraiah Baire
DOI:10.1002/asia.201900745
日期:2019.9.16
We report the discovery of an anomalous reaction of 2-(alkynonyl)alkynylbenzenes under AgI catalysis for the selective formation of isocoumarins. This reaction is previously undocumented for 2-(alkynonyl)alkynylbenzenes in terms of the reaction mechanism and the product formed. Water (H2 O18 ) labeling studies suggested a possible mechanistic pathway in which the initial formation of a pyrylium ion
Evidence for concerted processes in the course of the homoallenylic transposition
作者:Chahinez Aouf、Nicolas Galy、Maurice Santelli
DOI:10.1016/j.tet.2013.02.048
日期:2013.4
The hydrolysis of β-allenic tosylates produces mainly 2-methylenecyclobutanols resulting from a homoallenylic participation along with isomeric 2-methylenecyclobutanol minor products coming from a 1234–1243 rearrangement. Structures of various cyclopropylvinyl carbocations involved in the course of the hydrolysis have been determined by computational studies. For acyclic tosylates, the hydrolysis of
On the [2,3]-sigmatropic rearrangements of sulfenate esters derived from alkenynols: synthesis of vinylallene and vinylacetylene sulfoxides.
作者:Eugène M.G.A. van Kruchten、William H. Okamura
DOI:10.1016/s0040-4039(00)87011-2
日期:1982.1
The reactions of various alkenynols with phenylsulfenyl chloride result in the formation of either vinylallene sulfoxides or vnylacetylene sulfoxides, depending on the substitution pattern of the starting material.
Lewis acid-catalyzed oxidative rearrangement of tertiary allylic alcohols mediated by TEMPO
作者:Jean-Michel Vatèle
DOI:10.1016/j.tet.2009.11.104
日期:2010.1
Two methods for the oxidative rearrangement of tertiary allylic alcohols have been developed. Most of tertiary allylic alcohols studied were oxidized to their corresponding transposed carbonyl derivatives in excellent to fair yields by reaction with TEMPO in combination with PhIO and Bi(OTf)3 or copper (II) chloride in the presence or not of oxygen. Other primary oxidants of TEMPO such as PhI(OAc)2
Copper-Catalyzed Aerobic Oxidative Rearrangement of Tertiary Allylic Alcohols Mediated by TEMPO
作者:Jean-Michel Vatèle
DOI:10.1055/s-0029-1217545
日期:2009.8
A mild method for the oxidativerearrangement of tertiary allylic alcohols to β-substituted enones using a TEMPO/CuCl 2 system, in the presence of molecular sieves, is described. Depending on the substrate, CuCl 2 was used in either a catalytic amount under an oxygen atmosphere or stoichiometrically.