89242-69-3Relevant academic research and scientific papers
One-pot two-step solvent-free rapid and clean synthesis of 2-(substituted amino)pyrimidines by microwave irradiation
Goswami, Shyamaprosad,Hazra, Anita,Jana, Subrata
experimental part, p. 1175 - 1181 (2009/12/25)
abs A series of diversely 2-(substituted amino)pyrimidines (along with ring substitution) has been synthesized under solvent- and catalyst-free microwave conditions from substituted guanidines and β-diketones. The substituted guanidines are synthesized from (S)-methylisothiourea sulfate and different amines (various alkyl, aryl, or heterocyclic and also chiral amines) under microwave irradiation. These two-step reactions are performed in one-pot without isolating any intermediate. This protocol has been successfully applied for the synthesis of bisaminopyrimidines and 2-substituted aminopyrimidines containing chiral moiety where chirality remains undisturbed.
Dihydropyrimidines and Related Structures. I. N2-Substituted 2-Pyrimidinamines and Dihydro-2-pyrimidinamines by Reaction of Phenylbutenones and Monosubstituted Guanidines
Wendelin, Winfried,Schermanz, Karl
, p. 65 - 69 (2007/10/02)
The reactions of monosubstituted guanidines 2 with phenylbutenones 7 and 10 exclusively yield N2-substituted 2-pyrimidinamines 8 and 9.The structure of the reaction products is proved and their differing stability is discussed.Action of methyl- and benzylguanidine respectively (2b,c) on 4-phenyl-3-buten-2-one (7) and of 2c on 1-phenyl-2-buten-1-one (10) under atmospheric oxygen affords aromatic N2-substituted 2-pyrimidinamines 9b and c.The dihydropyrimidines 8b and c, probable intermediates of the reactions, could not be isolated.In contrast, heating of arylguanidines 2d,e with 7 leads to stable dihydropyrimidinamines 8d and e, which can be isolated as bases.Addition of methanol to 8d yields 6-methoxy-2-pyrimidinamine 11d, boiling of 8d in DMF affords 9d.Under nitrogen, guanidine adds to 7 to yield aminopyrimidinol 13a, which is transformed by heating in benzene into pyrimidine 9a.The low stability of 8a-c is attributed to their strong basicity, the greater stability of 8d and e to their lower basicity.The structural formulae of 8d, e and 9b-d and their salts respectively were established partly (8e) by nmr and partly (9b-d) by comparison of the corresponding picrates with authentic samples .
Reactions of Monosubstituted Guanidines with 1-Phenyl-1-butane-1,3-dione
Wendelin, Winfried,Schermanz,Karl,Schweiger, Klaus,Fuchsgruber, Alfred
, p. 1371 - 1380 (2007/10/02)
Methyl-, benzyl- and phenylguanidine (2b-d) react with 1-phenyl-1,3-butanedione to yield exclusively N2-substituted 4-methyl-6-phenyl-2-pyrimidinamines 10b-d.The formation of isomeric N1-substituted 2(1H)-pyrimidinimines 11 or 12 cannot be observed.The structural formulae of 10b and c were proved by spectroscopical methods.The structure of the phenylguanidine-phenylbutanedione-condensate was determined by comparison and establishment of the identity of its picrate with an authentical sample of 10d-picrate, which had been synthetized from pyrimidinthione 13 (via methylthiopyrimidine 16*HCl).Boiling 13 with aniline in butanol yields thiodipyrimidine 15 (and not 10d). - (Keywords: 1,3-Butanedione, 1-phenyl, reactions with monosubstituted guanidines; β-Diketones, reactions with monosubstituted guanidines; Guanidines, monosubstituted, reactions with 1-phenyl-1,3-butanedione; Pyridmidine, 4-methyl-2-methylthio-6-phenyl, hydroiodide; 2-Pyrimidine-amines, 4-methyl-6-phenyl-N2-substituted, and salts; 2,2'-Thiodipyrimidine, 4,4'-dimethyl-6,6'-diphenyl)
