PHOTOCHEMICAL STUDIES + IRRADIATION OF TRIARYL PHOSPHATE ESTERS - NEW PHOTOCHEMICAL COUPLING REACTION
PHOTOCHEMICAL STUDIES + IRRADIATION OF TRIARYL PHOSPHATE ESTERS - NEW PHOTOCHEMICAL COUPLING REACTION
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DOI：
10.1021/ja00768a084
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发表时间：
1972-01-01
影响因子：
15
通讯作者：
MATSON, JA
中科院分区：
文献类型：
--
作者：
FINNEGAN, RA;MATSON, JA
R=烷基或芳基磷酸酯偶联反应（方程式1）涉及在某一阶段的氧化-还原序列。溶剂乙醇最有可能作为还原剂，事实上，我们已经分离出乙醛作为其2，4-二硝基苯腙衍生物。另一个对比特征是，在表I所列的任何实验中均未检测到光Fries产物（即羟基芳基膦酸酯）或溶剂分解产物（即磷酸二芳基乙酯、磷酸芳基二乙酯或磷酸三乙酯）。4缺乏，例如，来自磷酸三对甲苯酯的甲苯，来自磷酸三茴香酯的苯甲醚等，或任何相应的乙基醚，大大降低了反应过程中产生游离芳基、碳负离子或碳正离子的可能性。当等摩尔的磷酸三苯酯和磷酸三对甲苯酯的乙醇溶液经4.5小时辐照后，联芳基馏分中只得到联苯（产率21%，转化率4%）和4，4 ′-二甲基联苯（产率53%，转化率48%）。同样，当三对甲苯基磷酸和三对甲苯基磷酸的类似混合物（1）（a）光化学研究。八.关于本系列的第七部分，请参见参考文献2。(b)国家科学基金会（GP 5785）和国立卫生研究院（GM 11412）为这项工作提供了慷慨的财政支持。(2)R. A. Finnegan和D. Knutson，Tetrahedron Lett.，第3429（1968）号决议。(3)参考文献2和本系列的早期文章在此引用。(4)虽然通常会观察到相应的酚类，但它们在分析过程中（vpc）通过磷酸单芳基酯的热分解而产生。用硅胶柱层析法不能分离出它们。
RCOiAr—>-RAr+ C02(2) R= alkyl or aryl phosphate coupling reaction (eq 1) involves an oxida-tion-reduction sequence at some stage. The solvent ethanol most likely serves as reductant and, indeed, we have isolated acetaldehyde as its 2, 4-dinitrophenylhydrazone derivative. Another contrastingfeature is that neither photo-Fries products (ie, hydroxyaryl phosphonates) nor solvolysis products (ie, diaryl ethyl, aryl diethyl, or triethyl phosphate) were detected in any of the experiments listed in Table I. 4 The lack of, eg, toluene from tri-p-cresyl phosphate, anisóle from trianisyl phosphate, etc., or any of the cor-responding ethyl ethers, strongly diminishes the possi-bility that free aryl radicals, carbanions, or carbonium ions are produced during the reaction. When an equimolar mixture of triphenyl and tri-p-cresyl phosphates in ethanolsolution was irradiated for 4.5 hr, there was obtained only biphenyl (21% yield, 4% con-version) and 4, 4'-dimethylbiphenyl (53% yield, 48% conversion) in the biaryl fraction. Likewise, when a similar mixture of tri-p-cresyl phosphate and tri-p-(1)(a) Photochemical Studies. VIII. For part VII in this series, see ref 2.(b) Financial support for this work was generously provided by the National Science Foundation (GP 5785) and the National Institutes of Health (GM 11412).(2) R. A. Finnegan and D. Knutson, Tetrahedron Lett., 3429 (1968).(3) Reference 2 and earlier articles in this series cited therein.(4) Although the corresponding phenols were usually observed, they were shown to arise during the analysis (vpc) by thermal decomposition of the monoaryl phosphate. They could not beisolated by silica gel column chromatography.