Hydrocarbons cyanation

The NCO—CH2(CF2) CH2—OCN monomer series have been characterized by DSC, IR, H-NMR, 19F-NMR, 13C-NMR, and elemental analysis.8 Table 2.1 summarizes the characterization most pertinent to these cyanate ester monomers. The n = 5,1, and 9 members are missing. This is a reflection of the difficulty in obtaining the odd hydrocarbon diol precursors. The trend of a rapid melting point increase with increasing fluoromethylene sequence length is an indication that monomers with n > 10 will probably not be melt-processible since the onset of the cure exotherm in most purified monomers occurs at 200°C. 

Cyanation of aromatic hydrocarbons, also a carbon-carbon coupling reaction, is achieved in the case of anthracene in MeCN-Et4NCN to yield 54% 9,10-dicyanoanthracene [165]. The cyanation is simplified when it is carried out in an emulsion system (aqueous sodium cyanide, dichloromethane, and TBAHSO4). Its synthetic utility in this mode has been demonstrated for the preparation of 4-alkoxy-4-cyanobiphenyls, a class of liquid crystals [166]. 

The most common strategy for laboratory scale hydrocarbon functionalization is hydrogen atom abstraction followed by free radical recombination. Although the conversions are often low, the simplicity of the approach can in some cases make this the method of choice for preparing a particular target molecule. A representative procedure is the cyanation of 2,3-dimethylbutane to give a 77% yield of 2,2,3-trimethylbutanenitrile1. 

Aromatic hydrocarbons (including benzene), phenols, and phenolic ethers can be cyanated with trichloroacetonitrile, BrCN, or mercury fulminate Hg(ONC)2.36 In the case of CljCCN,... 

In this equation, E normally corresponds to hydrogen but can also be another group, e.g. -OCH3. The denotation E is used to show the interplay between nucleophiles and electrophiles in electroorganic reactions. Thus, due to the oxidative nature of the process, a nucleophile can be used as a reagent in an otherwise impossible substitution reaction. As an example of an anodic substitution process, electrochemical cyanation of an aromatic hydrocarbon can be mentioned ... 

There have been several recent investigations into the mechanism of photo-cyanation of aromatic hydrocarbons. The process with naphthalene, biphenyl, and phenanthrene has been subjected to a kinetic analysis the reactions in dry or aqueous methyl cyanide are shown to involve two transient species, the first of which is an ionic complex formed from a triplet excimer of the arene, or, in the presence of an electron acceptor, from a triplet exciplex. Reaction of the transient complex with the cyanide ion yields the radical ArHCN, and in aqueous methyl cyanide this second transient reacts with itself to produce dihydrocyano- and cyano-compounds. In dry methyl cyanide the radical species is oxidized to the cyano product. 

Alkyl derivatives of these cyanate compounds in which the alkyl radical is derived from a saturated hydrocarbon of the methane series are not of any special importance. When, however, we study another series of hydrocarbons known -as the unsaturated hydrocarbons we shall find important derivatives which occur in nature. We shall then refer to this study of the general relationships which we have here discussed. 

Aromatic hydrocarbons (including benzene), phenols, and phenolic ethers can be cyanated with trichloroacetonitrile, BrCN, or mercury fulminate I (ONC)2. In the case of CI3CCN, the actual attacking entity is probably CI3C C =NH, formed by addition of a proton to the cyano nitrogen. Secondary aromatic amines ArNHR, as well as phenols, can be cyanated in the ortho position with CI3CCN and BCl3. ... 

The synkinesis of isolable organized monolayers by the LB technique is not restricted to amphiphiles. They can also be obtained from stiff polymers with multiple hydrocarbon side-chains ( hairy rods ) . Regular and stable bilayers were obtained consisting of stiff rods made of cellulose or silicon phthalo-cyanate chains which were separated by fluid alkane regions. Furthermore the... 

In this chapter we deal first with compounds formed by metals containing the isoelectronic groups CN , Cl, and CO. (HCN and non-metal cyanides, and also cyanates and thiocyanates are included in Chapter 21.) We then describe briefly compounds of metals with hydrocarbon radicals or molecules other than olefine compounds of Pd and Pt (Chapter 27) and certain compounds of Cu and Ag (Chapter 25). 

The last two reactions are to be considered as cases of the normal Friedel-Crafts reaction, since the cyanate and mustard oil unite in the first phase with hydrochlorid add, forming an acid-chloride, which then reacts with the hydrocarbon with elimination of hydrochloric acid, e.g. -... 

Compounds such as urea and ammonium cyanate, which have the same composition but different constitution are called isomers. After this first example it has been found that there is an enormous number of isomers of organic compounds, especially hydrocarbons, in nature. Before clarifying these concepts in more detail... 

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