Efficient Synthesis of 4,4‘-Bi-1<i>H</i>-imidazol-2-ones from 5-Amino-α-imino-1<i>H</i>-imidazole-4-acetonitriles and Isocyanates
作者:Alice M. Dias、Isabel Cabral、M. Fernanda Proença、Brian L. Booth
DOI:10.1021/jo011192z
日期:2002.8.1
of a catalytic amount of DBU (1,8-diazabicyclo[5.4.0]undec-7-ene). The reaction of the N-arylamidine 6b, the synthetic precursor of the imidazole 1b, with benzyl isocyanate also led to the formation of 4,4'-bi-1H-imidazol-2-one 3b in quantitative yield. The imidazole intermediate 2b has been isolated and found to be identical with the compound obtained by reaction of the imidazole 1b and benzyl isocyanate
Synthesis of 6-cyano and 6-unsubstituted 2-aryl-8-oxopurine from a common 2-oxoimidazole precursor
作者:Magdi E.A. Zaki、M. Fernanda Proença
DOI:10.1016/j.tet.2010.11.064
日期:2011.1
The benzyl urea of diaminomaleonitrile, prepared from commercially available starting materials, was reacted with aromatic aldehydes at room temperature. Intramolecular cyclization of the product, in basic solution, generated a substituted 2-oxoimidazole. This compound proved to be a common precursor for 2-aryl-6-cyano-8-oxopurines upon treatment with acid and for 2-aryl-6-unsubstituted-8-oxopurines
由可商购的起始原料制备的二氨基马来腈的苄基脲在室温下与芳族醛反应。在碱性溶液中产物的分子内环化产生取代的2-氧代咪唑。在碱的存在下,经酸处理后,该化合物被证明是2-芳基-6-氰基-8-氧普尿烷的常见前体,对于2-芳基-6-未取代的-8-氧普尿烷是该化合物的常见前体。对这些简单而通用的反应的1 H NMR研究支持了该机制。