Oxidative Addition of Pd(0) to Ar−SO<sub>2</sub>R Bonds: Heck-Type Reactions of Sulfones
作者:José Luis García Ruano、José Alemán、Cristina García Paredes
DOI:10.1021/ol060608y
日期:2006.6.1
[reaction: see text] Phenyl vinyl sulfones and sulfoxides react with Pd(OAc)(2) to form styrylsulfoxides and sulfones according to the first Mizoroki-Heck reaction reported for these thio derivatives. Only sulfones are able to react by using catalytic amounts of Pd (up to 1 mol %) in the presence of Ag(2)CO(3). 1,2-Diphenylsulfonyl ethenes, alkynylphenyl sulfones, and other sulfones, less prone to act as acceptors
Conjugate Additions, Aza-Cope, and Dissociative Rearrangements and Unexpected Electrocyclic Ring Closures in the Reactions of 2-(2-Pyrrolidinyl)-Substituted Heteroaromatic Systems with Acetylenic Sulfones
作者:Mitchell H. Weston、Masood Parvez、Thomas G. Back
DOI:10.1021/jo101030b
日期:2010.8.6
sulfones proceeded via two pathways. The first involves conjugateaddition of the pyrrolidine to the acetylenic sulfone to afford a zwitterion, followed by dissociation of the C−N bond and recombination of the resulting carbocation and vinyl anion to afford the corresponding azepine derivative. The second comprises a cascade of conjugateaddition, aza-Cope rearrangement and anionic 6π electrocyclic ring-closure
Tandem Conjugate Additions and 3-Aza-Cope Rearrangements of Tertiary Allyl Amines and Cyclic α-Vinylamines with Acetylenic Sulfones. Applications to Simple and Iterative Ring Expansions Leading to Medium and Large-Ring Nitrogen Heterocycles
作者:Mitchell H. Weston、Katsumasa Nakajima、Thomas G. Back
DOI:10.1021/jo800600a
日期:2008.6.1
Tertiary acyclic allyl amines and tertiary cyclic α-vinyl amines undergo conjugate additions to acetylenic sulfones to produce zwitterion intermediates, followed by 3-aza-Cope rearrangements. In the case of cyclic α-vinyl amines, the process results in ring-expansion, providing a novel route to 9- to 17-membered cyclic amines. The Hammett plot for the reaction of 8b with 2a−2f shows ρ = +1.19, which
Asymmetric Diels–Alder reactions of sulphinyl-activated dienophiles obtained via a self-induced chiral oxidation
作者:Ottorino De Lucchi、Carla Marchioro、Giovanni Valle、Giorgio Modena
DOI:10.1039/c39850000878
日期:——
The Diels–Alder cycloaddition of activated vinyl sulphoxides (1), that are readily obtained by a self-inducedchiraloxidation, proceeds highly diastereoselectively to form the corresponding cycloadducts (4) that can be converted into 2-substituted norbornadienes(5) of high enantiomeric purity.
Self-induced diastereoselective oxidation of vinyl sulfoxides bearing a chiral hydroxy group as a way of preparation of optically active sulfinyl dienophiles and their use in the asymmetric Diels-Alder reactions to cyclopentadiene
作者:Ottorino De Lucchi、Vittorio Lucchini、Carla Marchioro、Giovanni Valle、Giorgio Modena