Imino reaction with alcohols

Phenylacetamide has been obtained by a wide variety of reactions from benzyl cyanide with water at 250-260° 6 from benzyl cyanide with water and cadmium oxide at 240° 6 from benzyl cyanide with sulfuric acid 7 8 by saturation of an acetone solution of benzyl cyanide with potassium hydrosulfide 9 from benzyl cyanide with sodium peroxide 10 by electrolytic reduction of benzyl cyanide in sodium hydroxide 11 from ethyl phenyl-acetate with alcoholic 12 or aqueous 13 ammonia from phenyl-acetic acid with ammonium acetate 14 or urea 15 from diazoacetophenone with ammoniacal silver solution 16 from phenyl-acetic acid imino ether hydrochloride and water 17 from acetophenone with ammonium poly sulfide at 215° 18 from benzoic acid 19 and by heating the ammonium salt of phenyl-acetic acid.20... 

The synthesis of ortho esters from nitriles is usually a two-step process involving first the formation of the imino ester hydrochloride and subsequent reaction with an alcohol. Several examples are described in Table I, even a glycol such as ethylene glycol can be used to obtain heterocyclic ortho esters, as shown in Eq. (11). 

PINNER REACTION. Formation of imino esters (alkyl imidates) by addition of dry hydrogen chloride to a mixture of a nitrile and an alcohol. Treatment of alkyl imidates with ammonia or primary or secondary amines affords amidines. while treatment with alcohols yields ortho-esters. 

A very wide range of nucleophiles other than water and alcohols has been shown to react with co-ordinated nitriles (Fig. 4-15). The reaction with ammonia or amines is a particularly convenient method for the preparation of amidine complexes. Specific examples of these reactions are presented in Fig. 4-16, illustrating the formation of amide, imino-ether or amidine complexes. 

Similarly, urea TV, 0-acetal 64 undergoes condensation reaction with weak carbon acids to afford acyclic 1,1-enediamines with the elimination of alcohol and amine42,95. A number of active methyl compounds such as an aliphatic ketone, acetophenone, imino ester and thioacetoamide has been successfully converted to 1,1-enediamines. Lactones, lactams and thiolactams condense with 64 to give enediamines 65 in moderate yields (equation 24). Very weakly activated methyl groups are also reactive towards urea A, 0-acetal 64, and 1,1-enediamines 66-71 are prepared from the corresponding reactants42,95. 

Excellent examples of this reaction are found in the preparations of acetamidine (91%) and nicotinamidine (60%). The conversion is accomplished by treatment of the imino ester hydrochloride with alcoholic ammonia or by the action of ammonium chloride on the free imino ester. The amidines are frequently isolated as salts such as the sulfates or picrates. N-Substituted amidines result when amines are used in place of ammonia. ... 

Modifications of these basic materials include the formation of the V-methanesu 1 tonate 36 which has been used for the synthesis of boronates used in allyl transfer reactions39 (Section D. 1.3.3.3.) and the attachment of the compounds to a chloromethylated polystyrene (Merrifield resin)40. The immobilized amino alcohol has been used as a catalyst for the addition of zinc alkyls to carbonyl compounds (Section D. 1.3.1.4.). 2,/ -Unsaturated dihvdrooxazoles have been prepared from such amino alcohols by reaction with imino ethers41 and used as chiral dienophiles in Diels-Alder reactions (Section D. 1.6.1.1.1.2.2.1.1.). 

N-Substituted S-chloroisothiocarbamoyl chlorides (197) react additively with isocyanates to form the highly reactive S-(N-chlorocarbonylamino)-isothiocarbamoyl chlorides (198) nearly quantitatively. These are cyclized to the 3,5-diones (199) by water or aqueous alcohol in a vigorous exothermic reaction, with evolution of hydrogen chloride.168,169 Aminolysis of 198 produces 5-imino-l,2,4-thiadiazolidin-3-ones (200).17°... 

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