Halogenated unsaturated

The saccharides represent a structurally diverse group of compounds, which are often derivatised with a variety of functional groups. The chemical modification of saccharides often involves the installation of a functional group that at an appropriate time can be converted into another functionality. In this chapter, synthetic methodologies for the preparation of halogenated, unsaturated and deoxygenated sugar derivatives will be discussed and furthermore methods for the introduction of amino, sulfate and phosphate moieties will be covered. 

The same is true of the alpha-beta-di-hdlogen acids, which, by the loss of halogen-hydrogen acid, yield halogen unsaturated compounds. 

Poly(2-chloro-1,3-butadiene) and other halogenated unsaturated polyhydrocarbons... 

Results for some other halogenated unsaturated polyhydrocarbons were reported in literature. For example, poly(perfluoro-4-chloro-1,6-heptadiene) upon heating between 320° C and 400° C is reported to completely volatilize [12]. Also, reports on chlorinated rubber show that by heating from ambient to 500° C, it generates almost quantitatively HCI, and in the later stages of reaction CH4, C2H4, and H2 [13],... 

The Favorskii rearrangement also occurs with di-, tri- and tetrahalo ketones and gives rise to (halogenated) unsaturated carboxylic acid derivatives. 

A full account has appeared of the reactions of polyhalogenoacroleins, keto-acetals, ethyl pyruvate, and various halogenated unsaturated ketones with dichloro- and dibromo-methylenetriphenylphosphoranes generated in situ. This dichloro-ylide reacted with the carbonyl of benzoyl cyanide in a normal olefin synthesis to give the unsaturated nitrile (31). 

Other types of halogenated unsaturated compounds, such as vinyl bromide or halogenated acrylics, can also be used as co-monomers ... 

Unsaturated phosphonates can be incorporated into the polymeric chain as comonomers, resulting in an appropriate flame-retardance at a proportion of about 40 per cent. As little as 12 to 15 per cent is satisfactory when halogenated unsaturated phosphonates are used. 

Eastman Chemical supplies triethyl phosphate and other phosphates to the plastics industry, where they can be used synergistically with halogens in flame-retarded and halogenated unsaturated polyesters, or replace antimony in products that need to be clear or translucent. They can be used in highly filled polymer systems, including ATH filled formulations. 

Table 24 Flammability of non-halogenated unsaturated polyester resin with expandable graphite and other fire retardants. Reprinted from (2000) Flame Retardants 2000, Interscience Commun, London 2000, p 105 [113] with permission... 

The thermal decomposition of halogenated and non-halogenated unsaturated polyester resins (UPR s), fire retarded by zinc hydroxystannate (ZHS) and cross-linked with styrene, has been investigated by thermogravimetiy (TG) and TG coupled on-line with Fourier transform infra red spectroscopy (TG-FTIR) or mass spectroscopy (TG-... 

---