Photochemical Reactivity of 1-Substituted-1-aza-1,4-dienes Promoted by Electron-Acceptor Sensitizers. Di-π-methane Rearrangements and Alternative Reactions via Radical-Cation Intermediates
作者:Diego Armesto、Maria J. Ortiz、Antonia R. Agarrabeitia、Santiago Aparicio-Lara、Mar Martin-Fontecha、Marta Liras、M. Paz Martinez-Alcazar
DOI:10.1021/jo026440l
日期:2002.12.1
series of beta,gamma-unsaturated imines, oxime acetates, and oxime methyl ethers, using 9,10-dicyanoanthrathene (DCA) or dicyanodurene (DCD) as electron acceptor sensitizers, affords the corresponding cyclopropanes resulting from 1-aza-di-pi-methane rearrangements via radicalcations. In some cases, alternative reactions of these intermediates occur to yield nitriles, dihydroquinolines, dihydronaphthalene
SmI<sub>2</sub>-Mediated 3-<i>exo-trig</i> Cyclization of β,γ-Unsaturated Carbonyl Compounds: Diastereoselective Synthesis of Cyclopropanols
作者:Mar Martin-Fontecha、Antonia R. Agarrabeitia、Maria J. Ortiz、Diego Armesto
DOI:10.1021/ol101666m
日期:2010.9.17
SmI2-mediated 3-exo-trig cyclizations of β,γ-unsaturatedcarbonylcompounds to generate cyclopropanols are not generally observed processes. The reported examples are limited to β,γ-unsaturatedcarbonylcompounds that possess ester groups conjugated with the alkene unit. The results of the current study show that this cyclization also occurs when other substitution patterns are present on the alkene
Efficient photochemical synthesis of 2-vinylcyclopropanecarbaldehydes, precursors of cyclopropane components present in pyrethroids, by using the oxa-di-π-methane rearrangement
作者:Diego Armesto、Maria J. Ortiz、Antonia R. Agarrabeitia、Noureddin El-Boulifi
DOI:10.1016/j.tet.2010.09.012
日期:2010.11
oxa-di-π-methane rearrangement (ODPM) to afford the corresponding cyclopropanecarbaldehydes 16a–f and 17 in yields ranging from 14% to 62% in addition in most cases to products resulting from decarbonylation. However, when 4-phenylbenzophenone is used as the photosensitizer ODPM products are obtained exclusively in almost quantitative yield. These are additional examples of the recently described, unexpected influence
Di-π-methane Reactions Promoted by SET from Electron-Donor Sensitizers
作者:Diego Armesto、Maria J. Ortiz、Antonia R. Agarrabeitia、Mar Martin-Fontecha
DOI:10.1021/ja0164428
日期:2001.10.1
A new photochemical synthesis of cyclopropanecarboxylic acids present in pyrethroids by the aza-di-π-methane rearrangement
作者:Diego Armesto、Mar G. Gallego、William M. Horspool、Antonia R. Agarrabeitia
DOI:10.1016/0040-4020(95)00527-f
日期:1995.8
A novel synthetic route to chrysanthemic acid, 2-cyclopentylidenmethyl-3,3-dimethylcyclopropanecarboxylic acid, fluorenespiro-2,2-dimethylcyclopropanecarboxylic acid and indenespiro-2,2-dimethylcyclopropanecarboxylic acid, all of them present in pyrethroids of known insecticidal activity, is described. The key step in the synthesis is the aza-di-n-rnethane rearrangement of some 1-aza-1,4,6-trienes