Reactions of {sup 1}:CX{sub 2} during chlorofluorocarbon pyrolysis
- Villanova Univ., Villanova, PA (United States)
Singlet carbenes are reactive intermediates which behave in a fashion quite different from radicals. In hydrocarbon and hydrochlorocarbon systems, radicals and radical chemistry typically dominate. However, in chlorofluorocarbon (CFC) and hydrochlorofluorocarbon (HCFC) systems, formation of perhalogenated singlet carbenes ({sup 1}:CX{sub 2}) has been observed. While radicals undergo abstraction reactions and addition to double bonds, singlet carbenes can insert into single bonds. Singlet carbenes are species which have two paired nonbonded electrons; since paired electrons have opposite spin, singlet carbenes can insert into single bonds. Triplet carbenes, in contrast, contain unpaired electrons and behave essentially like radicals. Formation of perhalogenated triplet carbenes ({sup 3}:CX{sub 2}) is less favorable in CFC and HCFC systems since the :CX{sub 2} singlet state is as much as 56 kcal/mol lower in energy than the triplet state. This paper discusses the results of chlorofluorocarbon pyrolysis in helium at different temperatures and with carbene insertion.
- OSTI ID:
- 254693
- Report Number(s):
- CONF-940813-; TRN: 96:003482-0032
- Resource Relation:
- Conference: 208. American Chemical Society (ACS) national meeting, Washington, DC (United States), 21-26 Aug 1994; Other Information: PBD: 1994; Related Information: Is Part Of 207th ACS national meeting. Volume 39, Nos. 1, 2, 3 and 4; PB: 1304 p.
- Country of Publication:
- United States
- Language:
- English
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