Valence Tautomerism of Vinyl-Substituted Three-Membered Heterocycles. I. Conversion of 1,2-Divinylethylene Oxide to 4,5-Dihydrooxepine

Agrandissement Thermique de Cycles à Trois Chaînons Vinyliques

“…(34) pendant ces etudes, effectuees avec des melanges d'isomeres, n'ont pas permis de preciser le mecanisme de l'isomerisation. tropique f3.31 de type Cope qui fournit un heterocycle a sept chainons(schema8).La formation exclusive d'isomere cis lorsque R"=CH3 est en faveur du passage par un etat de transition bateau.AH* etA S *(18)(25)(36) .…”

Kinetics of the Gas Phase Reactions of (+)-trans-2,3-Divinyloxirane

“…those arising from l b and 4, they are also sterically very crowded. The stereochemical studies of Chuche and coworkers (10) indicate that a n isomerization about the carbon-oxygen bond of the carbonyl ylide must occur, the cis-oxirane being ruled out since it gives rise t o the dihydrooxepine exclusively (6). lsomerization a t the carbonyl ylide stage is similarly capable o f explaining the trans-cis isomerization of oxirane (resulting in the formation of 5).…”

“…Both cis-and trans-2,3-divinyloxirane ( l b and 2b) have been synthesized and their conversions to vinyldihydrofuran (4) and 4 3 -dihydrooxepin (5) have been observed (5,6 For personal use only.…”

cRh‐Catalyzed Hydroformylation of Divinylglycol: An Effective Way to Access 2,7‐Dioxadecalin‐3,8‐diol

“…As such, DVG already proved effective as a building block in the synthesis of natural products and polyenes . DVG and derivatives are also actually used as a cross‐linking agent and monomers for the production of polymers . The conversion of the biomass‐derived products is usually achieved either by classical organic reactions or under catalytic conditions .…”