An isolable disilyne anion radical and a new route to the disilenide ion upon reduction of a disilyne.
An isolable disilyne anion radical and a new route to the disilenide ion upon reduction of a disilyne.
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DOI：
10.1021/ja066762x
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发表时间：
2007-01
影响因子：
15
通讯作者：
Rei Kinjo;M. Ichinohe;A. Sekiguchi
中科院分区：
文献类型：
--
作者：
Rei Kinjo;M. Ichinohe;A. Sekiguchi
1,1,4,4-四基[双（三甲基硅基）甲基]-1,4-二异丙基四基-2-炔1与tBuLi反应生成二二烯基锂衍生物2，该产物是通过单电子转移反应使LiH横跨Si - Si三键正式加成。用x射线晶体学对溶剂分离离子对进行了表征。体积庞大的SiiPr[CH(SiMe3)2]2基团以反式排列，硅-硅双键长度为2.2034(9)a。1与等量的石墨钾（KC8）在THF中反应产生二苯乙烯阴离子自由基4，其以钾盐形式分离为对空气和水分极为敏感的深棕色晶体。通过x射线晶体学分析确定了4的分子结构，其分子结构为反弯结构（av 113.4°），中心Si - Si键长为2.1728(14)a。电子自旋共振（ESR）研究表明，4的两个中心硅原子之间存在未配对电子离域。
The reaction of 1,1,4,4-tetrakis[bis(trimethylsilyl)methyl]-1,4-diisopropyltetrasila-2-yne 1 with tBuLi produced disilenyllithium derivative 2, the product of the formal addition of LiH across the Si⋮Si triple bond through a single electron transfer reaction. The solvent-separated ion pair of the disilenide 3 was characterized by X-ray crystallography. The bulky SiiPr[CH(SiMe3)2]2 groups are arranged in the trans fashion with a silicon−silicon double bond length of 2.2034(9) A. The reaction of 1 with an equivalent amount of potassium graphite (KC8) in THF produced the disilyne anion radical 4, which was isolated in the form of its potassium salt as extremely air- and moisture-sensitive dark brown crystals. The molecular structure of 4 was established by X-ray crystallography, which showed a trans-bent structure (av 113.4°) with the central Si−Si bond length of 2.1728(14) A. An electron spin resonance (ESR) study indicates delocalization of the unpaired electron between the two central silicon atoms of 4.