Alkylammonium tosylates

A hot solution of the amide (10 mmol) in acetonitrile (30 ml) was added to a stirred mixture of HTI (3.92 g, 10 mmol) and acetonitrile (20 ml). After refluxing for a suitable period of time (15 min-15 h), on cooling the alkylammonium tosylate crystallized out in high yield. 

Some bridgehead amines such as 4-iodo-l-cubylamine (58%) and 1-adamantyl-amine (85%) were also obtained in this way [47]. The direct formation of alkylammonium tosylates is advantageous because of the instability of some amines of this type. No special precautions, as with BTI, were needed with HTI which, however, did not work with some cyclic carboxamides also, malonamide did not undergo degradation but tosyloxylation, affording a-tosyloxymalonamide (81%) [48]. The reaction involved the intermediacy of TV-phenyliodonium salts (RCONHI + Ph TsO-), which were actually isolated from carboxamides and [methoxy(tosyloxy)iodo]benzene [49]. 

Hydroxy(tosyloxy)iodobenzene (HTIB 30) is another hypervalent organoiodine compound which acts as a Hofmann reagent, converting aliphatic carboxamides to alkylammonium tosylates in refluxing acetonitrile (equation 23). 

A large variety of ILs of high purity with water content below lOOppm and halide content below lOppm are now available commercially. These include numerous iV-alkylpyridinium, 7V,7V -dialkylimidazolium, alkylammonium and alkylphosphonium salts, covalent hydrophobic ILs (e.g. l,2-dimethyl-3-propyliniidazolium bis(trifluoromethylsulfonyl)imide, task-specific ILs, Bronsted acidic ILs (e.g. 3-[triphenylphosphonio]propane-l-sulfonic acid tosylate), nitrile-fiinction sed ILs, perfluorinated ILs (e.g. tetrabutylammonium nonafluorobutane sulfonate, BASF Basionics (e.g. 1,2,3-trimethylimidazolium methyl sulfate), and TOMATS for heavy metal extraction (e.g. methyltrioctylammonium thiosalicylate)... 

The effects of increasing the concentration of initiator (i.e. increased conversion, decreased and broader PDi) and reducing the reaction temperature (i.e. decreased conversion, increased M and narrower PDi) for the polymerizations in ambient-temperature ionic Uquids are the same as observed in conventional solvents. Mays et al. reported similar results and, in addition, used NMR to investigate the stereochemistry of the PMMA produced in (BMIMjlPFej. They found that the stereochemistry is almost identical to that for PMMA produced by free radical polymerization in conventional solvents [28]. The homopolymerization and copolymerization of several other monomers are also reported. Similar to vdiat was found by Noda and Watanabe, in many cases the polymer was not soluble in the ionic liquid and thus phase separated [28,29]. Free radical polymerization of n-butyl methacrylate in ionic liquids based on imidazolium, pyridinium, and alkylammonium salts as solvents was investigated with a systematic variation of the length of the alkyl substituents on the cations, and employing different anions such as tetrafluoroborate, hexafluorophosphate, tosylate, triflate, alkyl sulfates and dimethyl phosphate [31]. 

Ionic liquids are a good example of the industrial chemicals of the future. They consist of an organic cation, such as alkylimidazolium, alkylpyridinium, alkylphosphonium or alkylammonium, and an organic or inorganic anion, such as tetrafluoroborate, hexafluorophosphate, tosylate or bis(trifluoro-methylsulfonyl)imide. Table 1 presents some common examples of ionic... 

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