Solvent selection in synthesis of 4-(1-arylfluoroethoxy)quinazolines and thienopyrimidines
作者:Jin Han、Eirik Sundby、Bård Helge Hoff
DOI:10.1016/j.jfluchem.2013.05.011
日期:2013.9
The nucleophilic aromatic substitution of 4-chloroquinazoline and 6-bromo-4-chlorothieno[2,3-d]pyrimidine with 1-aryl-2-fluoroethanols as nucleophilies has been studied focusing on the use of carbonate bases in combination of environmental acceptable solvents. The conversion rate depended on the solvent properties, the acidity of the nucleophile and the nature of the base. By using acetonitrile as
研究了以1-芳基-2-氟乙醇为亲核试剂对4-氯喹唑啉和6-溴-4-氯噻吩并[2,3- d ]嘧啶的亲核芳香取代反应,重点是结合环境可接受的溶剂使用碳酸盐碱。转化率取决于溶剂性质,亲核试剂的酸度和碱的性质。通过使用乙腈作为反应介质并且以K 2 CO 3为碱,可以将2,2,2-三氟-,2,2-二氟-和2-氟-1-苯基乙醇有效地偶联到4-氯嘧啶上。或者,使用Cs 2 CO 3,可以缩短这些底物的反应时间,并且非氟化醇的偶联也进行得很好。还发现叔丁醇是氟代醇转化中合适的反应介质。对4-烷氧基嘧啶的水解稳定性的测试表明,氟化和非氟化衍生物在酸性条件下均不稳定,而在碱性介质中,氟烷氧基衍生物比其非氟化衍生物更稳定。