Fluorothiocarbonyl compound

A very versatile route to fluorothiocarbonyl compounds is dehydrohalogena-tion of fluorine-containing mercaptans. In the case of removal of HF, sodium fluoride is a very convenient dehydrohalogenating agent. 

One of the great surprises of fluorothiocarbonyl chemistry is the ease with which these compounds undergo free-radical polymerization. This behavior is unique among thiocarbonyl compounds. Though thioacetone polymerizes in free-radical systems, it does not do so with anything like the avidity of fluorothiocarbonyl compounds. Thioacetone does not copolymerize with compounds containing carbon-carbon unsaturation, which is a most important property of fluorothiocarbonyl compounds. 

Middleton, W.J. Fluorothiocarbonyl compounds. HI. Diels-Alder reactions. J. Org. Chem. 1965, 1390-1394. 

Phosphorus pentasulfide (s. a. under C H N) Replacement of halogen by sulfur Fluorothiocarbonyl compounds... 

Poly(thiocarbonyl fluoride) and related fluorothiocarbonyl compounds have been the subject of extensive study in recent years and at least two reviews (Sharkey, 1969 1972) have been devoted to these materials. Commercial production of the material in the near future, however, seems unlikely. 

The fluorothiocarbonyl isothiocyanates may also be reacted successfully in place of the thiocarbonyl compounds (21), e.g.,... 

Fluorine-substituted thiocarbonyl compounds have been studied even more intensively than thioformaldehyde and thioacetone. These compounds have a very rich chemistry of which polymerization is only a part. The simplest member of this class is fluorothiocarbonyl fluoride, CF2==S, which also forms the most interesting polymers. Other members that have been investigated include a variety of fluorothioacyl halides and a number of fluorothioketones. Because... 

The main problem is how to generate free radicals at low temperatures. It was discovered this can be done by using the trialkylborane-oxygen redox couple. Prior to the studies on thiocarbonyl compounds, Furukawa and Tsuruta (68) had used a mixture of trialkylboranes and oxygen for vinyl polymerizations, and studies by Fordham and Sturm (69) and Zutty and Welch (70) had confirmed them as free-radical polymerizations. For the fluorothiocarbonyl work (39), it was shown that at - 78° C the reaction of a trialkylborane and oxygen proceeds cleanly to an alkylperoxydialkylborane, V. 

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