Search

Schmidt reaction (sodium azide/sulfuric acid) of 1,5- and of 1,8-dichloroanthraquinones gives, in each case, both of the theoretically possible lactams (2,3,5,6-dibenzoazepin-4,7-diones). Two of the four theoretically possible lactams have been identified from Schmidt reaction of 1- and 2-chloroanthraquinones respectively. Methods used include: (a) preferential hydrolysis of one lactam and identification of the isomeric aminoanthraquinone formed on cyclodehydration of the resulting amino acid; (b) identification of the isomeric aminoanthraquinone(s) formed on direct treatment of a lactam (or mixture of lactams) by sulfuric acid; (c) cleavage by potassium tert-butoxide of the amino acid formed by preferential hydrolysis of one lactam and identification of the resulting benzoic acid as its methyl ester.

Ethyl-α-cyano-β-aminoacrylates (I) have been used as intermediates in the synthesis of pyrimidine derivatives1,2 and I(R=H,CH3, C6H5) have been obtained by the condensations of ethyl cyanoacetate with amidines and iminoethers, in relatively poor yields.2 We now report that both biprotic and monoprotic carbothioamides-thioformamide, thiobenzamides, phenylthioacetamide, quinazolin-4(3H)-thione and pyrrolidin-2(1H)-thione condense with ethyl bromocyanoacetate, with extrusion of sulphur, to form ethyl α-cyano-β-aminoacrylate (I, R=H), ethyl α-cyano-β-aminocinnamates (I, R=-C6H5,-C6H4-OCH3, -C6H4-NO2,P), ethyl α -cyano-β-amino-β-benzylacrylate (I, R=-CH2C6H5), ethyl-α-cyano Δ4(3H), quinazolineace tate (II) and ethyl α-cyano-Δ2,α pyrrolidineacetate (III) (Table) respectively.