Modelling radical-initiated DNA cleavage by vinyl epoxides
作者:Anthony P. Breen、John A. Murphy
DOI:10.1039/c39930000191
日期:——
Allyloxy radicals, formed by addition of thio radicals to vinyl epoxides, are shown to abstract hydrogen atoms and to add to alkene π-bonds in reactions which model the chemistry that would be required to induce DNA damaqe this suggests that vinyl epoxides could have uses as radiosensitizers for treatment of resistant tumours.
Investigation of the origin and synthetic application of the pseudodilution effect for Pd-catalyzed macrocyclisations in concentrated solutions with immobilized catalysts
作者:Elisabeth Brehm、Rolf Breinbauer
DOI:10.1039/c3ob41020j
日期:——
Immobilized Pd-complexes allowed macrocyclisations via the Tsuji-Trost-reaction in concentrated solutions. Systematic studies suggest that the origin of this pseudodilution effect is neither film diffusion nor gel diffusion, but the reduction in conformational freedom of intermediates and intramolecular prenucleophile activation. In contrast a pseudodilution effect could not be observed for Sonogashira-
Stereospecific Ring Expansion of Chiral Vinyl Aziridines
作者:Matthew Brichacek、Mauricio Navarro Villalobos、Alexandra Plichta、Jon T. Njardarson
DOI:10.1021/ol200263g
日期:2011.3.4
In this report, it is demonstrated that chiral vinyl aziridines can be stereospecifically ring expanded. This synthetic approach allows controlled access to chiral 2,5-cis- or 2,5-trans-3-pyrroline products from starting materials with the appropriate aziridine geometry. Twenty three ringexpansion examples, most of which feature a stereospecific cyclization, are presented.
Abstract The synthesis of a range of racemic 1-acyl-2-vinylcyclopropanes by using two different methodologies is studied. We have developed a copper-catalyzed process for converting diazoketones into 1-acyl-2-vinylcyclopropanes and a sulfur-ylide-mediated procedure which allows, in only two steps, a simplified access to 1-acyl-2-vinylcyclopropanes with alkyl or aryl substituents on the alkene moiety
Sustainable Palladium-Catalyzed Tsuji–Trost Reactions Enabled by Aqueous Micellar Catalysis
作者:Nicholas R. Lee、Farbod A. Moghadam、Felipe C. Braga、Daniel J. Lippincott、Bingchun Zhu、Fabrice Gallou、Bruce H. Lipshutz
DOI:10.1021/acs.orglett.0c01329
日期:2020.7.2
reactions, can be run under micellarcatalysis conditions featuring not only chemistry in water but also numerous combinations of reaction partners that require low levels of palladium, typically on the order of 1000 ppm (0.1 mol %). These couplings are further characterized by especially mild conditions, leading to a number of cases not previously reported in an aqueous micellar medium. Inclusion of diverse