Brown R James, Brooks Andrew C, Griffiths Jon-Paul, Vital Betrand, Day Peter, Wallis John D
School of Biomedical and Natural Sciences, Nottingham Trent University, Nottingham, UK.
Org Biomol Chem. 2007 Oct 7;5(19):3172-82. doi: 10.1039/b709823e. Epub 2007 Aug 20.
Short synthetic routes to a range of BEDT-TTF derivatives functionalised with two, four or eight hydroxyl groups are reported, of interest because of their potential for introducing hydrogen bonding between donor and anion into their radical cation salts. The cycloaddition of 1,3-dithiole-2,4,5-trithione with alkenes to construct 5,6-dihydro-1,3-dithiolo[4,5-b]1,4-dithiin-2-thiones is a key step, with homo- or hetero-coupling procedures and O-deprotection completing the syntheses. The first synthesis of a single diastereomer of tetrakis(hydroxymethyl)BEDT-TTF, the cis,trans product, was achieved by careful choice of O-protecting groups to facilitate separation of homo- and hetero-coupled products. Cyclisation of the trithione with enantiopure 1R,2R,5R,6R-bis(O,O-isopropylidene)hex-3-ene-1,2,5,6-tetrol (from D-mannitol) gave two separable diastereomeric thiones, which can be transformed to enantiomeric BEDT-TTF derivatives with four or eight hydroxyl groups.
报道了一系列用两个、四个或八个羟基官能化的BEDT-TTF衍生物的短合成路线，因其在自由基阳离子盐中引入供体与阴离子之间氢键的潜力而备受关注。1,3-二硫杂环戊烯-2,4,5-三硫酮与烯烃的环加成反应以构建5,6-二氢-1,3-二硫并[4,5-b]1,4-二硫因-2-硫酮是关键步骤，通过均相或异相偶联程序以及O-去保护完成合成。通过精心选择O-保护基团以促进均相和异相偶联产物的分离，首次合成了四(羟甲基)BEDT-TTF的单一非对映异构体，即顺式、反式产物。三硫酮与对映体纯的1R,2R,5R,6R-双( O,O -亚异丙基)己-3-烯-1,2,5,6-四醇（由D-甘露糖醇制得）环化得到两种可分离的非对映异构硫酮，它们可转化为具有四个或八个羟基的对映体BEDT-TTF衍生物。
