Pyrimidine誘導体の合成研究 (第7報)

2-Alkoxymethylene-3-alkoxypropionitrileおよびその異性体について

抄録

It had earlier been reported that the alkylation of 2-sodioformyl-3-alkoxypropionitrile (II or III) with dialkyl sulfate afforded cis- and trans-2-alkoxymethylene-3-alkoxypropionitrile (IV, V, and VI) but later examinations revealed that the substances obtained in this reaction were still impure. Further purifications showed that besides the cis and trans isomers of the foregoing nitriles, another isomer of low boiling point has been formed. This new isomer was found to have C=C bond from the Raman spectra although this point was not clear from its infrared spectrum. Ozonolysis of this isomer afforded formaldehyde, proving the presence of endo-methylene group. Catalytic reduction resulted in the rapid absorption of one mole of hydrogen to form 2-dialkoxymethyl-propionitrile (X and XI). The latter was confirmed from its infrared spectrum and formation of 2, 5-dimethyl-4-aminopyrimidine (XII) by condensation with acetamidine. These experimental results have proved that the new-type isomer obtained by the foregoing reaction is 2-dialkoxymethyl-acrylonitrile (VII, VIII, and IX).