Photodetosylation of sulfonamides initiated by electron transfer from an anionic sensitizer.
摘要:
A new and efficient photosensitized process for the detosylation of a wide variety of sulfonamides is presented. The excited beta-naphthoxide anion is used as sensitizer, in methanol as solvent. Electron transfer from the excited naphthoxide anion to the electron-accepting sulfonamide leads, in the presence of sodium borohydride, to the recovering of amines after cleavage of the radical anion.
Fluorescent Quenching of the 2-Naphthoxide Anion by Aliphatic and Aromatic Halides. Mechanism and Consequences of Electron Transfer Reactions
作者:Juan E. Argüello、Alicia B. Peñéñory
DOI:10.1021/jo026518y
日期:2003.3.1
The fluorescent excitedstate of the 2-naphthoxide ion (1) is quenched by aliphatic and aromatic halides according to an electron-transfer mechanism, with generation of the corresponding alkyl and aryl radicals by a concerted or consecutive C-X bond fragmentation reaction. Whereas bromo- and iodobenzene follow a concerted ET mechanism (C-X, BDE control), 1-bromonaphthalene exhibits a stepwise process
Kinetic investigation of azo coupling reactions between naphthols and 4-methoxy- and 4-nitrobenzenediazonium o-benzenedisulfonimides has been carried out for comparison with the related benzenediazonium tetrafluoroborates. The data clearly indicate that the two kinds of diazoniumsalts show very similar reactivities. This fact emphasizes that arenediazonium o-benzenedisulfonimides, which are very stable
The reactivity of oxygen nucleophiles with aryl radicals in the SRN1 mechanism
作者:María T. Baumgartner、Adriana B. Pierini、Robert A. Rossi
DOI:10.1016/s0040-4039(00)74201-8
日期:1992.4
The photostimulated reaction of 2-naphthoxide ions 1 with o-dihalobenzenes in liquid ammonia gives the halosubstituted product 4 and the cyclized substituted product 5. This is the first report about the coupling of an aromatic σ radical with an oxygen functionality in the chain propagation cycle of the SRN1mechanism.
Photostimulated reaction of aryl iodides with 2-naphthoxide ions by the SRN1 mechanism
作者:A.B Pierini、M.T Baumgartner、R.A Rossi
DOI:10.1016/0040-4039(88)85181-5
日期:1988.1
The photostimulated reactions of p-iodoanisole () and 1-iodonaphthalene () with 2-naphthoxide ions in liquid ammonia gave the corresponding 1-aryl-2-naphthols as the only substitution product. These reactions are proposed to proceed the SRN1mechanism for nucleophilic aromatic substitution.
Oxamyl dipeptide caspase inhibitors developed for the treatment of stroke
作者:Steven D. Linton、Teresa Aja、Peter R. Allegrini、Thomas L. Deckwerth、Jose-Luis Diaz、Bastian Hengerer、Julia Herrmann、Kathy G. Jahangiri、Joerg Kallen、Donald S. Karanewsky、Steven P. Meduna、Kip Nalley、Edward D. Robinson、Silvio Roggo、Giorgio Rovelli、Andre Sauter、Robert O. Sayers、Albert Schmitz、Robert Smidt、Robert J. Ternansky、Kevin J. Tomaselli、Brett R. Ullman、Christoph Wiessner、Joe C. Wu
DOI:10.1016/j.bmcl.2003.12.106
日期:2004.5
Structural modifications were made to a previously described acyl dipeptide caspase inhibitor, leading to the oxamyl dipeptide series. Subsequent SAR studies directed toward the warhead, P2, and P4 regions of this novel peptidomimetic are described herein. (C) 2004 Elsevier Ltd. All rights reserved.