A divergent strategy for the facile preparation of various enantioenriched phenylthio-substituted lactones was developed based on Lewis base/Brønsted acid co-catalyzed thiolation of homoallylic acids. The acid-controlled regiodivergent cyclization (6-endo vs. 5-exo) and acid-mediated stereoselective rearrangement of phenylthio-substituted lactones were explored. Experimental and computational studies
基于路易斯碱/布朗斯台德酸共催化的均烯丙基酸的硫醇化反应,开发了一种简便制备各种对映体富集的苯硫基取代的内酯的策略。探索了酸控制的区域发散环化(6-endo vs. 5-exo)和苯硫基取代的内酯的酸介导的立体选择性重排。进行了实验和计算研究以阐明区域选择性和对映选择性的起源。计算结果表明,CO和CS键的形成可能会同时发生,而不会形成通常认为的催化剂配位的硫鎓离子中间体,而且底物和SPh之间的潜在π-π堆积是对映确定步骤的重要因素。最后,
Synthesis of 2-aryl-4-hydroxy-5-thio substituted 1,3-thiazin-6-ones<i>via</i>sulfenylation of 2-aryl-4-hydroxy-[1,3]thiazin-6-ones with sulfenyl chlorides
作者:J. V. N. Vara Prasad
DOI:10.1002/jhet.5570330608
日期:1996.11
2-aryl-4-hydroxy-5-thio substituted 1,3-thiazin-6-ones were synthesized for human immunodeficiency virus-1 protease inhibition. These compounds were synthesized by the treatment of 4-hydroxy-5-thio substituted-1,3-thiazin-6-ones with the corresponding sulfenylchlorides. The products were obtained in good isolated yields, inspite of the presence of bulkyl substitutents at the ortho position of phenyl sulfenyl chloride