Azoles. part 12. 1 synthesis of thieno-extended purines: First example of the imidazo[4′,5′:4,5]thieno[3,2-d]pyrimidine ring system
作者:David W. Hawkins、Brian Iddon、Darren S. Longthorne
DOI:10.1016/0040-4020(95)00845-y
日期:1995.11
1 -Benzyl-4-bromoimidazole-5-carbonitriles were synthesised by several methods and shown to be surprisingly resistant to nucleophilic displacement of the bromine atom (e.g. by sulfanylacetamide under various conditions). 1 -Benzyl-4-bromo-2-(methylsulfanyl)imidazole-5-carbonitrile underwent Br → Li exchange with butyllithium (THF/-100 °C) and the resulting 4-lithiated imidazole was treated successively