WebApr 2, 2012 · The base-induced dehydrohalogenation of vinyl halides and allyl halides often gives low yields of al- lenes because of the competing reaction to alkynes; alkynes can either be formed by direct elimination from vinyl halides or by isomerization of the allene first formed to the isomeric alkyne. WebPortal de la producció científica dels investigadors de la Universitat de Barcelona.
Stereochemistry of vinyl cations and vinylic substitutions
WebMay 26, 2015 · To the best of our knowledge, this example is the first of an organomagnesium-catalyzed isomerization of alkynes. Notably, the reactions proceeded through temporally separated autotandem catalysis, thus allowing the isolation of the allene or internal alkyne species in good yields. Mechanistic experiments suggested that the … WebDec 30, 2024 · The alkyne zipper reaction involves the isomerization of an internal triple bond to a terminal position. Since the isomerization involves the formation of a product that is less thermodynamically stable than the original isomer, the alkyne zipper reaction has been coined a “contra-thermodynamic” process [ 1 ]. chevelle bumper brackets
A.E.Favorskii
WebApr 21, 2024 · Using a combination of ultrafast spectroscopies, we investigate how such excited-state symmetry breaking affects the photochemical reactivity of quadrupolar and … WebMay 19, 2024 · Abstract. UV-activated alkyne–alkene [2 + 2] cycloaddition has served as an important tool to access cyclobutenes. Although broadly adopted, the limitations with UV light as an energy source ... WebConsidering that the base-promoted isomerization of alkynes to allenes is well-known, 16 we assume that the reaction could proceed by the attack of the imidazolidinone enolate to the central carbon of the generated allene. 17 This assumption was supported by the requirement of two equivalents of base: one equivalent for the enolate formation and … good spa and golf resorts in florida