Trichloroacetonitrile, reaction

The reaction of ethyleneimine with nittiles in the presence of HBF gives A -imidazolines (229). If trichloroacetonitrile [545-06-2] (R = Cl) is used as the nitrile component, the intermediate amidine can be isolated (230). 

Benzyl groups are usually introduced by the Williamson reaction (Section 3.2.3). They can also be prepared under nonbasic conditions if necessary. Benzyl alcohols are converted to trichloroacetimidates by reaction with trichloroacetonitrile. These then react with an alcohol to transfer the benzyl group.183... 

O-Allyl imidate esters undergo [3,3]-sigmatropic rearrangements to /V-allyl amides. Trichloromethyl imidates can be made easily from allylic alcohols by reaction with trichloroacetonitrile. The rearrangement then provides trichloroacetamides of IV-allylamines.260... 

The later publication [1] reveals that the title compound is in fact a relatively stable compound. The previously attempted preparation of the then unknown compound from trichloroacetonitrile, sodium azide and ammonium chloride (0.14 0.42 0.2 mol) by an analogous established method [2], but at lower initial temperature because of the exothermic reaction, gave, after vacuum evaporation of solvent, an oily product. When sampled with a pipette, this evolved gas and then exploded violently. It was thought that an azidomethyltetrazole may have been formed by displacement of chloro-substituent(s) by the excess azide employed [3], An alternative hypothesis which involved isomerisation of the title compound to the open chain azidoazomethine [4] was discounted, because no trace of this could be detected [1]. 

The Mukaiyama-Hoshino reaction between a nitroalkane and phenyl isocyanate generates a nitrile oxide, and this method has been used in the synthesis of 1,2,4-oxadiazoles as discussed in CHEC-II(1996) <1996CHEC-II(4)179>. In a more recent advance, nitroethane undergoes ultrasound-mediated cycloaddition with trichloroacetonitrile to give the extremely useful (see Equation 11) 5-trichloromethyl-l,2,4-oxadiazole 228 (Equation 45) <1995TL4471>. 

CF3CN and CCI3CN leads to the corresponding substituted oxadiazolines (74, 829). Thus, reactions of (746) and (747), derived from 1-deoxynojirimycin with trichloroacetonitrile in toluene at room temperature leads to bicyclic compounds (748) and (749) (Scheme 2.308). 

However, the successful isolation of an iminoborane derivative in the reaction of trichloroacetonitrile with diborane indicated that the stability of imino-boranes is not only a function of the nature of the borane but also of that of the imine 16>. 

The reaction of tris(organothio)boranes with nitriles leads to B—S substituted iminoboranes. 1,2-addition of tris(methylthio)borane or tris(phenylthio) borane to trichloroacetonitrile yields the monomeric products (XIV) or (XV)32). 

Closure of the oxadiazole ring is still achieved through cycloaddition between pyridine iV-oxides and isocyanates, affording adducts such as 142 (Scheme 38) <1995T6451>. Nonaromatic imine fV-oxides exhibited similar reactivities, since azasugar-derived fV-oxides as a mixture of 143 and 144 underwent cycloaddition reactions in the presence of phenyl isocyanate or trichloroacetonitrile. Compounds 145 and 146 (Scheme 39) were obtained from the aldoxime W-oxide 143 two other regioisomeric heterocycles arose from the ketoxime derivative 144 <1996T4467>. 

Previous investigations of heterogeneous sonochemistry have involved ultrasonic extraction of pollutants from sediments and ultrasound assisted reactions employing solid catalysts. However, more extensive quantitative results are needed concerning sonochemistry in environmentally relevant systems. We report results of a preliminary set of experiments, involving the ultrasonic irradiation of bromobenzene, trichloroacetonitrile, and chloropicrin in the presence of silica solids (15 im and 10 nm). 

The data in Fig. 7 demonstrate that in the presence of 15 micron solid particles, there is a slight or moderate impact on destruction kinetics. The destruction rate constant of trichloroacetonitrile (TCA) decreases by approximately 10% when the silica particle concentration is increased from 0 to 100 g L 1. In the presence of 10 nm silica (Fig. 8), the trends are similar, with slight to moderate decreases in the reaction rate constant as the silica particle concentration increases. 

Allenylcobaloximes, e.g. 26, react with bromotrichloromethane, carbon tetrachloride, trichloroacetonitrile, methyl trichloroacetate and bromoform to afford functionalized terminal alkynes in synthetically useful yields (Scheme 11.10). The nature of the products formed in this transformation points to a y-specific attack of polyhaloethyl radicals to the allenyl group, with either a concerted or a stepwise formation of coba-loxime(II) 27 and the substituted alkyne [62, 63]. Cobalt(II) radical 27 abstracts a bromine atom (from BrCCl3) or a chlorine atom (e.g. from C13CCN), which leads to a regeneration of the chain-carrying radical. It is worth mentioning that the reverse reaction, i.e. the addition of alkyl radicals to stannylmethyl-substituted alkynes, has been applied in the synthesis of, e.g., allenyl-substituted thymidine derivatives [64],... 

Trichloroacetimidates, CCl,C(NH)OR, have been prepared under mild conditions by the reactions of alcohols with trichloroacetonitrile under basic conditions promoted by catalytic amounts of tetra-n-butylammonium hydrogen sulphate [72]. The procedure is far superior to the standard methods which normally require anhydrous reaction conditions. 

The complex (PPh4)[Os NC(CCl3)NCCl(CCl3) Cl5] may be regarded as an imido complex of osmium(VI), made by the reaction of OS2CI10 with trichloroacetonitrile and has been characterized by X-ray structural studies. The Os—N distance of 1.97 A is slightly shorter than that expected for a single bond. 

In contrast, the 5-phenyliminothiatriazoline (323) reacts as a masked 1,3-dipole with a variety of electrophilic nitriles. Tosyl cyanide and ethyl cyanoformate both react with (323) in refluxing chloroform to give initially (324) which then isomerizes to (325) as the reaction proceeds (Scheme 71) <91JHC333>. When the solvent is changed to acetone the reaction with the nitriles proceeds faster due to the formation of the adduct (326) which is capable of undergoing cycloaddition/elimination reactions at 20 °C. Trichloroacetonitrile does not react with (323) in chloroform solution in acetone,... 

Aminothiatriazole (328) reacts with a number of aryl cyanates at 0°C to afford 3-substituted 5-amino-l,2,4-thiadiazoles (17) in moderate yields. 5-Aminothiatriazole (328) also reacts with trichloroacetonitrile to give (17) (R = CCI3) in 92% yield. When these reactions are carried out at 30 °C, the thiadiazoles (17) react with a second mole of aryl cyanate to give the amidino compounds (329) (Scheme 72) <85JOCl295>. 

Previous methods for the preparation of salts of geranyl diphosphate and other allylic isoprenoid diphosphates are based on condensation between the alcohol and inorganic phosphate by trichloroacetonitrile as originally reported by Cramer and modified by Popjak The reaction generates a complex mixture of organic and inorganic polyphosphates which must be separated by chromatography. The desired diphosphate ester has been prepared on small... 

Reaction between trichloroacetonitrile and Ph2CN2 at low temperatures yields 67 other electron-deficient nitriles give different products. It is possible that the reaction proceeds via an unstable 3//-1,2,4-triazole intermediate, which loses N2 to form a nitrile ylide before adding a second mole of nitrile as in Scheme 13. 

Allyl alcohols readily react with trichloroacetonitrile to give the corresponding trichloroacetimidates 145. Activation of the double bond with electrophilic reagents results in ring closure to yield oxazolines 146. The most commonly employed electrophiles include iodine, iodine monochloride, phenylselenyl chloride, and mercuric trifluoroacetate. Other nitriles including cyanogen bromide and N,N-dimethylcyanamide can also be used. Since oxazolines readily hydrolyze to amides, the net effect of this reaction sequence is to produce p-amino alcohols 147 from an allyl alcohol. This strategy has been employed in numerous total syntheses of natural products. Examples are listed in Table 8.18 (Fig. 8.7 Scheme 8.43). ° ... 

Halogenated acetonitriles are not produced on an industrial scale. Trichloroacetonitrile has been used on a limited basis in the past as a pesticide. Several halogenated acetonitriles have been detected in chlorinated drinking-water in a number of countries as a consequence of the reaction of chlorine with natural organic substances. The only known route of human exposure is through chlorinated drinking-water (lARC, 1991). 

The reacting species is a rather weak electrophile and, therefore, only particularly reactive aromatics are suitable substrates. Consequently, the reaction is restricted for polyhydric phenols and their ethers, and reactive heterocycles. With strong acidic systems, such as AICI3 in halogenated benzene solvents, alkylben-zenes can react at more elevated temperatures (>50°C). Trichloroacetonitrile works also well with nonactivated aromatics. The 12 chloroimine, the protonated nitrile (13), or the nitrile coordinated with the Lewis acid are possible involved electrophiles. 

Methyl isatogenate and 2-phenylisatogen react with tetracyanoethyl-ene, or trichloroacetonitrile, in boiling xylene to give quinazolones (154 R = C02Me, Ph).63,72 No reaction occurs with acetonitrile, and N-benzoylanthranilic acid is formed when 2-phenylisatogen is treated with potassium cyanide (see also Section III,A,1). No mechanism has been proposed for this unusual reaction. 

Some reactions of sulfur trioxide with dialkylcyanamides (77ZC222), trichloroacetonitrile (77ZOR222) and a combination of nitriles and alkenes (66USP3235549) are given in Scheme 29. In the reaction with dialkylcyanamides a second product (252 X = NR2) is also formed. 

Trichloroacetimidates are the only type of imino ethers to have found some application in solid-phase synthesis. Trichloroacetimidates can readily be prepared from support-bound alcohols by treatment with trichloroacetonitrile and a base (Entry 6, Table 13.18). Because trichloroacetimidates are good alkylating agents, this reaction offers a convenient alternative for converting support-bound aliphatic alcohols into alkylating agents. Trichloroacetimidates prepared from Wang resin or from hydroxymethyl polystyrene are quite stable and can be stored for several months without decomposition [253],... 

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