Ethene, bromo chloro

The impact of deposition on global distribution has been noted for the CFC replacements hydro-chlorofluorocarbons (HCFCs), the chlorinated solvents tetrachloroethene (PCE), and trichloro-ethene (TCE), as these compounds undergo gas phase oxidation and photochemical degradation, resulting in the formation of carbonyl halides (e.g., CCI2O) and haloacetyl halides (e.g., bromo-, chloro-, and fluoroacetates). As these compounds are polar and water soluble, they are transported via aerosols, rain, and fog, which impacts their tropospheric lifetime and depositional fluxes (Rompp et al., 2001 de Bmyn et al., 1995). It is not clear whether and to what extent there is evidence of latitudinal fractionation of these compounds. 

The photodissociation of l-bromo-2-chloroethane at 193 nm demonstrated that there were no stable bromoethyl or chloroethyl radicals formed. Dissociation of these radicals is rapid and affords ethene. 1-Chloro-1,1,3,3,3-pentafluoropropane can be made regioselectively by the photochlorination of 1,1,1,3,3-pentafluoropentane. 

Ethene, bromo-Ethene, chloro-Ethene, 1,1-clichloro-... 

The cw-l,2-bis(diphenylphosphino)ethene complexes [Fe(Ph2PCH=CHPPh2)2X2], X = C1 or Br, undergo pressure-induced spin-state transitions at about 8kbar for the chloro complex, about 60 kbar for the bromo complex. The difference is ascribed to the difference in ligand field strengths and lattice cooperativity. ... 

Reaction of 1-bromo- and l-chloro-2-(4-morpholino)-l,2-diphenyl-ethene with phenyllithium in benzene to give 2-(4-morpholino)-l,2-diphenyl-ethene [202]. 

Aiming at better 1,2-di(thien-3-yl)ethenes, compounds with different substituents on the cyclopentene ring were targeted. Thus, the idea of acylating 2-bromo-5-methylthiophene (44, R=Br) emerged. Unfortunately, the desired product was not obtained, and instead, the bromine substituent migrated to C-3, and acylation took place at C-2. However, 2-chloro-5-methylthiophene (44, R=C1) was smoothly converted into the desired diketcme giving a 98% yield under Friedel-Crafts conditions (Scheme 48) [63, 66],... 

---