959-02-4Relevant articles and documents
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Fieser
, p. 2329,2338 (1931)
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Birch Reduction of Aromatic Compounds by Inorganic Electride [Ca2N]+?e- in an Alcoholic Solvent: An Analogue of Solvated Electrons
Yoo, Byung Il,Kim, Ye Ji,You, Youngmin,Yang, Jung Woon,Kim, Sung Wng
supporting information, p. 13847 - 13853 (2018/11/23)
Birch reduction of aromatic systems by solvated electrons in alkali metal-ammonia solutions is widely recognized as a key reaction that functionalizes highly stable π-conjugated organic systems. In spite of recent advances in Birch reduction with regard to reducing agent and reaction conditions, there remains an ongoing challenge to develop a simple and efficient Birch reaction under mild conditions. Here, we demonstrate that the inorganic electride [Ca2N]+?e- promotes the Birch reduction of polycyclic aromatic hydrocarbons (PAHs) and naphthalene under alcoholic solvent in the vicinity of room temperature as a solid-type analogy to solvated electrons in alkali metal ammonia solutions. The anionic electrons from electride [Ca2N]+?e- are transferred to PAHs and naphthalene via alcoholysis in a polar cosolvent medium. It is noteworthy that a high conversion yield to the hydrogenated products is ascribed to the extremely high electron transfer efficiency of 98%. This simple protocol utilizing an inorganic electride offers a direct and practical strategy for the reduction of aromatic compounds and provides an outstanding reducing agent for synthetic chemistry.
Determination of the effective redox potentials of SmI2, SmBr2, SmCl2, and their complexes with water by reduction of aromatic hydrocarbons. Reduction of anthracene and stilbene by samarium(II) iodide-water complex
Szostak, Michal,Spain, Malcolm,Procter, David J.
, p. 2522 - 2537 (2014/04/17)
Samarium(II) iodide-water complexes are ideally suited to mediate challenging electron transfer reactions, yet the effective redox potential of these powerful reductants has not been determined. Herein, we report an examination of the reactivity of SmI2(H2O)n with a series of unsaturated hydrocarbons and alkyl halides with reduction potentials ranging from -1.6 to -3.4 V vs SCE. We found that SmI 2(H2O)n reacts with substrates that have reduction potentials more positive than -2.21 V vs SCE, which is much higher than the thermodynamic redox potential of SmI2(H2O) n determined by electrochemical methods (up to -1.3 V vs SCE). Determination of the effective redox potential demonstrates that coordination of water to SmI2 increases the effective reducing power of Sm(II) by more than 0.4 V. We demonstrate that complexes of SmI2(H 2O)n arising from the addition of large amounts of H 2O (500 equiv) are much less reactive toward reduction of aromatic hydrocarbons than complexes of SmI2(H2O)n prepared using 50 equiv of H2O. We also report that SmI 2(H2O)n cleanly mediates Birch reductions of substrates bearing at least two aromatic rings in excellent yields, at room temperature, under very mild reaction conditions, and with selectivity that is not attainable by other single electron transfer reductants.
