Abstract: Aryl(alkyl)substituted dihydropyrimidinyliden-2-(I,VI) and -6-(II) cyanoacetic esters in acetic acid react with fuming nitric acid at 10-degrees-C to form pyrimidinylnitrocyanoacetic esters (III, VIII, X) with 80-95 % yields. The latter compounds have been partly transformed into pyrimidine-substituted hydroxycyanoacetic esters IV, VII, XI) by treatment of their reaction mixtures of water with different acidity. It has been found that keeping the compouds (III, VIII, X) on silica gel in chloroform solution results in their dealkoxycarbonylation with production of new heterocyclic ylidene derivatives - the corresponding pyrimidinylidennitroacetonitriles (V, IX, XII) with 90-95 % yields. In the 95 % H2SO4 solution 5-phenyl-1,2-dihydropyrimidinylidencyanoacetic ester (Ia) was nitrated by 1 mole of fuming nitric acid exclusively into the para-position of the phenyl group. The other aryl-substituted 2- and 6-ylidene derivatives, containing the 2- or 4(6)-phenyl groups produce complex reaction nixtures of isomeris products in these conditions. The methyl-substituted dihydropyrimidinyliden cyanoacetic esters have not been nitrated into the methyl groups in acetic acid or 95 % H2SO4 solutions. Composition and structure of reaction products (III-XII) were confirmed by analytical and spectral (IR, UV and PMR) data (see the table).

Cite: Oleynik I.V. , Zagulyaeva O.A.
CHEMICAL-PROPERTIES OF YLIDENE DERIVATIVES OF AZINES .6. THE NITRATION OF THE ARYL (ALKYL) SUBSTITUTED DIHYDROPYRIMIDINYLIDENCYANOACETIC ESTERS
SIBIRSKII KHIMICHESKII ZHURNAL. 1992. N4. P.117-124. WOS

Identifiers:

Web of science

WOS:A1992KK37900017