Studies on Quinazolines. 11. Intramolecular Imidate-Amide Rearrangement of 2-Substituted 4-(ω-Chloroalkoxy)quinazoline Derivatives. 1,3 -O → N Shift of Chloroalkyl Groups via Cyclic 1,3-Azaoxonium Intermediates
作者:Grace Shiahuy Chen、Shivaramayya Kalchar、Chun-Wei Kuo、Chih-Shiang Chang、Cyril O. Usifoh、Ji-Wang Chern
DOI:10.1021/jo0263420
日期:2003.3.1
The omega-chloroalkylation of 2-substituted quinazolin-4(3H)-one derivatives 1 and 2 with Br-(CH(2))(n)-Cl (n = 2-4) and the intramolecular imidate-amide rearrangement of the alkylated products are described. At room temperature, the 2-phenyl substituent promoted O-alkylation, whereas the less steric 2-benzyl group led to a higher ratio of N-alkylation. The investigation of the O-alkylated products
2-取代的喹唑啉-4(3H)-一衍生物1和2与Br-(CH(2))(n)-Cl(n = 2-4)的ω-氯烷基化以及该化合物的分子内亚氨酸酯酰胺重排描述了烷基化产物。在室温下,2-苯基取代基促进了O-烷基化,而较少的空间2-苄基导致较高的N-烷基化比例。对O-烷基化产物4-ω-氯代烷氧基喹唑啉的研究表明,ω-氯乙基和ω-氯丙基从氧到氮的迁移应该是通过五元和六元环状1,3-氮杂氧鎓中间体进行的分子内迁移,分别。重排和亲核取代之间的竞争导致分别由4a,b和6a,b的亲核取代形成7a,b和8a,b。