117381-06-3Relevant academic research and scientific papers
SYNTHESIS OF NEW 1,3-DIOXEPIN DERIVATIVES
Tahnh, Naciye,Sirkecioglu, Okan,Mirzalar, Filiz
, p. 679 - 682 (2007/10/03)
Using cis-2-buten-1,4-diol and mono and dicarbonyl compounds eleven new 4,7-dihydro-1,3-dioxepin derivatives were synthesized.Structures were proved by spectroscopic methods.
Preparation of racemic and enantiomerically pure cyclic ketene acetals
Diaz-Ortiz,Diez-Barra,De La Hoz,Prieto
, p. 1935 - 1942 (2007/10/02)
Cyclic ketene acetals have been prepared from a-haloaldehyde dimethylacetals by transacetalization and subsequent elimination in PTC without solvent conditions. No racemization has been observed when an enantiomerically pure diol has been used. Stability and storage conditions have been studies.
Cyclisation of 2-Substituted 2-Bromomethyl-1,3-dioxacyclohept-5-enes; Hydrogen Transfer Reactions of 1,3-Dioxacyclohept-5-enes and 1,3-Dithiacyclohept-5-enes
Hindson, Andrew C.,MacCorquodale, Finlay,Walton, John C.
, p. 871 - 877 (2007/10/02)
2-Bromomethyl-1,3-dioxacyclohept-5-enes (2-bromomethyl-4,7-dihydro-1,3-dioxepins), containing an additional substituent at the 2-position, cyclise to afford 1-substituted 2,7-dioxabicyclooctanes on treatment with tributyltin hydride.The rate constants for cyclisation of the 2-methyl- and 2-phenyl-4,7-dihydro-1,3-dioxepin-2-ylmethyl radicals are 8.4 * 105 and 4.9 * 105 s-1 respectively at 298 K.Hydrogen is readily abstracted from the 4- and 7-positions of 4,7-dihydro-1,3-dioxepins by tert-butoxyl radicals to give 4,7-dihydro-1,3-dioxepin-4-yl radicals which have been characterised by EPR spectroscopy.The Arrhenius parameters for inversion of the 'flap' conformers have been determined from the exchange-broadened spectra of the 2,2-dimethyl and 2,2-diethyl radicals.The analogous radicals, expected on hydrogen abstraction from 1,3-dithiacyclohept-5-enes (4,7-dihydro-1,3-dithiepins), cannot be spectroscopically observed.Instead, the same spectrum, which we attribute to a degradation intermediate, is obtained from a series of 2,2-dialkyl-4,7-dihydro-1,3-dithiepins.
