Free radical addition of cyclopentane and cyclohexane to halogeno derivatives of 1,2-difluoroethene

Trihaloethenes as versatile building blocks for organic synthesis

“…Despite having three electron withdrawing chlorine substituents, TCE (1) is capable of nucleophilic addition to formaldehyde (21) under strongly acidic conditions (Scheme 3). This reaction was first reported by Prins in 1932, who claimed that the final product was 3,3′-oxybis(2-chloropropanoic acid).…”

“…Some trihaloethenes are used as monomers for the synthesis of halogenated polymers (2-bromo-1,1-difluoroethene (4, BDFE)), 20 or for radical addition reactions (2-chloro-1,1-difluoroethene ( 6)). 21 Although trihaloethenes are generally available from commercial sources, iodine containing derivatives are far less common. Scheme 1 outlines the four approaches involved in the stereoselective synthesis of differentially substituted trihaloethenes.…”

“…A related reaction reported by the Sandford group relies on the radical hydroalkylation of fluorinated trihaloethenes with cyclopentane (67a) and cyclohexane (67b) (Scheme 15). 21 The alkyl radicals, generated by γ-ray irradiation or treatment with di-tert-butyl peroxide, regioselectively substitute the gemdifluoro carbon atom. The authors suggest that the regioselectivity is governed by the little sterical hindrance and the increased electrophilicity of this position.…”

An Efficient Synthesis of 1-chloro-2,2-difluoroethylene via the Reductive Dechlorination of 1,2,2-trichloro-1,1-difluoroethane

“…2,3 These products can be used as heat exchange materials, refrigerants, foaming agents, solvents, cleaning agents, polymerisation media, polyolefin and polyurethane expansion agents, gas dielectrics and flame retardants. 4 2,2-Dichloro-1,1,1-trifluoroethane is a new type of foaming agent, which is also used as a refrigerant and cleaning agent.…”

“…1-Chloro-2,2-difluoroethylene is a raw material 1 and key intermediate for the production of fluorine-containing textile finishing agents, fluorosurfactants, organic silicon fluorine modified resins and other fluorine containing fine chemicals. 2,3 These products can be used as heat exchange materials, refrigerants, foaming agents, solvents, cleaning agents, polymerisation media, polyolefin and polyurethane expansion agents, gas dielectrics and flame retardants. 4 2,2-Dichloro-1,1,1-trifluoroethane is a new type of foaming agent, which is also used as a refrigerant and cleaning agent.…”