α-膦鎓碳正离子逐步还原为结晶性磷自由基阳离子和吖啶基-磷叶立德。

Stepwise Reduction of an α-Phosphonio-Carbocation to a Crystalline Phosphorus Radical Cation and an Acridinyl-Phosphorus Ylide.

作者信息

Hudnall Todd W, Dorsey Christopher L, Jones James S, Gabbaï François P

机构信息

Department of Chemistry and Biochemistry, Texas State University, San Marcos, TX, 78666, USA.

Department of Chemistry, Texas A&M University, College Station, TX, 77843, USA.

出版信息

Chemistry. 2016 Feb 24;22(9):2882-6. doi: 10.1002/chem.201504744. Epub 2016 Jan 7.

DOI:10.1002/chem.201504744

PMID:26629680

Abstract

We have synthesized the dicationic α-phosphonio-carbocation 1(2+) , which can be regarded as a two-electron oxidized phosphorus ylide. Carbocation 1(2+) exhibits two reversible reduction waves at -0.28 and -0.90 V (vs. Fc(+) /Fc) indicating that both the radical cation 1(.+) and the neural phosphorus ylide 1 can be generated. Indeed, reduction of 1(2+) with Zn afforded 1(.+) as a dark green solid that was characterized by XRD and EPR spectroscopy, and reduction with Mg(Ant)⋅(THF)3 gave 1, which was characterized by (1) H and (31) P NMR spectroscopy. Computational analyses reveal the stepwise population of a C-P π bonding orbital upon reduction of 1(2+) .

摘要

我们合成了双阳离子α-膦鎓碳正离子1(2+)，它可被视为双电子氧化的磷叶立德。碳正离子1(2+)在-0.28和-0.90 V（相对于Fc(+)/Fc）处表现出两个可逆还原波，这表明可以生成自由基阳离子1(·+)和中性磷叶立德1。实际上，用锌还原1(2+)得到深绿色固体1(·+)，通过X射线衍射和电子顺磁共振光谱对其进行了表征，用Mg(Ant)·(THF)3还原得到1，通过(1)H和(31)P核磁共振光谱对其进行了表征。计算分析表明，1(2+)还原时C-P π键轨道逐步填充。