Sulfimidation of thioether groups—a versatile method for modifying and linking thia/oxa crowns
作者:Mark R. J. Elsegood、Paul F. Kelly、Gillian Reid、Alexandra M. Z. Slawin、Paul M. Staniland
DOI:10.1039/b802903b
日期:——
Reaction of the mixed thioether/ether crowns [9]aneO2S 1, [12]aneO3S 2 and [18]aneO4S23 with one mol. equivalent of the aminating agent MSH (o-mesitylsulfonylhydroxylamine) in Et2O results in the formation of the mono-sulfimidated systems [9]aneO2(SNH2)}+1a, [12]aneO3(SNH2)}+2a and [18]aneO4S(SNH2)}+3a, while using two mol. equivalents of MSH with 3 gives the disulfimidium cation [18]aneO4(SNH2)2}2+3b. All of these species have been isolated in good yields as the [mesSO3]â (mes = 2,4,6-Me3C6H2) salts and can be readily converted to the [BPh4]â salts by metathesis with Na[BPh4]. Treatment of 1a or 2a with lithium diisopropylamide (LDA) and N-bromosuccinimide (NBS) at â78 °C, followed by addition of a further equivalent of the parent thia/oxa crown, gives monocationic N-bridged sulfimide bicyclic compounds (4 and 5 respectively), in which the crowns are linked by the sulfimidic nitrogen. Reaction of 3a with LDA and NBS leads to formation of the ([18]aneO4S2)N}+ cation 6 which exhibits an intramolecular SâNâS bridge. Crystallographic studies on representative examples of each compound type are described, together with their spectroscopic properties.
硫醚/醚混合冠[9]aneO2S 1、[12]aneO3S 2 和[18]aneO4S23 与 1 mol.当量的胺化剂 MSH(邻甲磺酰羟胺)在 Et2O 中生成单亚硫酸化体系 [9]aneO2(SNH2)}+1a、[12]aneO3(SNH2)}+2a 和 [18]aneO4S(SNH2)}+3a。3,则可得到二亚硫酰阳离子[18]aneO4(SNH2)2}2+3b。所有这些物质都以良好的产率分离出了[mesSO3]â(mes = 2,4,6-Me3C6H2)盐,并可通过与 Na[BPh4] 发生偏析反应而容易地转化为[BPh4]â盐。将 1a 或 2a 与二异丙基酰胺锂(LDA)和 N-溴代琥珀酰亚胺(NBS)在â78 °C下进行处理,然后再加入一个当量的母体噻/氧冠,就会得到单配位 N-桥接的亚硫酰亚胺双环化合物(分别为 4 和 5),其中的冠是由亚硫酰亚胺氮连接的。3a 与 LDA 和 NBS 反应生成([18]aneO4S2)N}+阳离子 6,该阳离子具有分子内 SâNâS 桥。文中介绍了对每种化合物的代表性实例进行的晶体学研究及其光谱特性。