Facile Syntheses of Oxazolines and Thiazolines with <i>N</i>-Acylbenzotriazoles under Microwave Irradiation
作者:Alan R. Katritzky、Chunming Cai、Kazuyuki Suzuki、Sandeep K. Singh
DOI:10.1021/jo0355092
日期:2004.2.1
Microwave reactions of 2-amino-2-methyl-1-propanol (2) or 2-aminoethanethiol hydrochloride (4) with readily available N-acylbenzotriazoles 1a−j in the presence of SOCl2 produced 2-substituted 2-oxazolines 3a−j in 84−98% yields and 2-substituted thiazolines 5a−i in 85−97% yields, respectively. With use of this method chiral oxazoline 6, bisoxazoline 7, bisthiazoline 8, and 5,6-dihydro-4H-1,3-oxazines
在SOCl 2的存在下,2-氨基-2-甲基-1-丙醇(2)或2-氨基乙硫醇盐酸盐(4)与易于获得的N-酰基苯并三唑1a - j的微波反应产生了2-取代的2-恶唑啉3a - j分别以84-98%的产率和2-取代的噻唑啉5a - i的产率为85-97%。使用该方法时,手性恶唑啉6,双恶唑啉7,双噻唑啉8和5,6-二氢-4 H -1,3-恶嗪9或10还制备了82-96%的产率。这些结果证明了N-酰基苯并三唑在温和条件下和微波辐射下反应时间短的情况下在恶唑啉和噻唑啉制备中的新应用。