On the Mechanism of the Selenolactonization Reaction with Selenenyl Halides
- 15 August 2006
- journal article
- Published by American Chemical Society (ACS) in The Journal of Organic Chemistry
- Vol. 71 (19), 7293-7306
- https://doi.org/10.1021/jo0610457
Abstract
The mechanism of selenocyclization reactions of β,γ-unsaturated acids and their derivatives has been studied. The reactions of (E)-4-phenyl-3-butenoic acid 10 and its silyl and alkyl esters with benzeneselenenyl chloride (PhSeCl) and bromide (PhSeBr) have been examined by VT-NMR and in situ IR spectroscopic methods. Whereas the reactions of the acid 10 in the presence of a base were irreproducible and complicated, reactions of the silyl esters were clean and spontaneously and quantitatively afforded a chloroselenylation adduct at −70 °C as a single (Markovnikov) isomer. This adduct underwent three processes as the temperature was raised: (1) reversal to the starting materials, (2) isomerization to the anti-Markovnikov product, and (3) cyclization to the selenolactone 12. All of these processes are believed to proceed via a seleniranium ion the intermediacy of which was established by independent synthesis and spectroscopic identification. The reversible formation of chloro selenide adducts was unambiguously established by crossover experiments. The reaction of 10 with PhSeBr was found to be rapid but thermodynamically unfavorable at room temperature.Keywords
This publication has 21 references indexed in Scilit:
- Iterative, stereoselective homologation of chiral polyalkoxy aldehydes employing 2-(trimethylsilyl)thiazole as a formyl anion equivalent. The thiazole route to higher carbohydratesThe Journal of Organic Chemistry, 1989
- Conformation and Cope rearrangement of sym-oxepin oxidesJournal of the American Chemical Society, 1979
- Hydrogen-deuterium exchange kinetics of the C-2 protons of imidazole and histidine compoundsJournal of the American Chemical Society, 1973
- Electron spin resonance spectra of bicyclic nitroxide radicals. 7-Azabenzonorbornadiene-7-oxyl and 7-azabenzonorbornene-7-oxylJournal of the American Chemical Society, 1973
- Quantitative evaluation of intramolecular strong hydrogen bonding in the gas phaseJournal of the American Chemical Society, 1973
- Darstellung und Eigenschaften von Tris‐(β‐chloräthyl) phosphinoxid und Bis‐(β‐chloräthyl)‐(chlormethyl)‐phosphinoxid. 43. Mitteilung über organische Phosphorverbindungen [1]Helvetica Chimica Acta, 1970
- Zur Kenntnis der Sulfen‐ und Selenensäuren und ihrer Derivate. 9. Mitteilung Additions‐ und Substitutionsreaktionen organischer Selenverbindungen mit unpolaren und polaren ÄthylenenHelvetica Chimica Acta, 1958
- Sulfenyl CarboxylatesJournal of the American Chemical Society, 1957
- BOOK REVIEWSJournal of the American Chemical Society, 1950
- Ueber Lactonsäuren, Lactone und ungesättigte SäurenEuropean Journal of Organic Chemistry, 1892