NaOH (30%) solution was used in dehydrohalogenation
of epoxy resin .
Two mechanisms dehydrohalogenation
molecular elimination and C-Cl bond fission are discussed.
The resulting intermediate then undergoes dehydrohalogenation
followed by reductive elimination, which regenerates the catalyst and couples the other two fragments together via a new carbon-nitrogen bond.
014 mot/100 g mainly due to side reactions such as dehydrohalogenation
This represented the evolution of trimellitate plasticizing oil, combined with the dehydrohalogenation
of the chlorinated polyethylene.
The major abiotic transformation or degradation processes include hydrolysis, oxidation-reduction, dehydrohalogenation
, and photolysis (Wolfe et al.
and Related 1,2-Elimination Reactions.
Various authors have reported HPTC and related chlorinated pesticides degradation by dehydrohalogenation
and dehalogenation mechanism [23 31].
This indicates that the dehydrohalogenation
reaction does not take place under our experimental conditions.
Because of the lower carbon--bromine bond strength (209 kJ/mol) when compared to chlorine in chlorobutyl rubber (327 kJ/mol), bromobutyl rubber can readily undergo dehydrohalogenation
, as illustrated in figure 5.
Stabilization is critical in halobutyls in order to impede thermal dehydrohalogenation
and premature crosslinking.
The addition of Br2 to enone 17a followed by dehydrohalogenation
, involving E1cB mechanism, afforded (Alpha) a"bromoenone 19 (the immediate use of this compound in the next reaction is strongly recommended since it tends to decompose upon standing even at low temperature in dark and dry conditions).