Waniek Sven D, Klett Jan, Förster Christoph, Heinze Katja
Institute of Inorganic Chemistry and Analytical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, D-55128 Mainz, Germany.
Beilstein J Org Chem. 2018 May 7;14:1004-1015. doi: 10.3762/bjoc.14.86. eCollection 2018.
A series of four ferrocenyl ester compounds, 1-methoxycarbonyl- (), 1,1'-bis(methoxycarbonyl)- (), 1,1',3-tris(methoxycarbonyl)- () and 1,1',3,3'-tetrakis(methoxycarbonyl)ferrocene (), has been studied with respect to their potential use as redox mediators. The impact of the number and position of ester groups present in - on the electrochemical potential is correlated with the sum of Hammett constants. The / -/ redox couples are chemically stable under the conditions of electrolysis as demonstrated by IR and UV-vis spectroelectrochemical methods. The energies of the C=O stretching vibrations of the ester moieties and the energies of the UV-vis absorptions of - and - correlate with the number of ester groups. Paramagnetic H NMR redox titration experiments give access to the chemical shifts of - and underline the fast electron self-exchange of the ferrocene/ferrocenium redox couples, required for rapid redox mediation in organic electrosynthesis.
研究了一系列四种二茂铁基酯化合物，即1-甲氧基羰基-（）、1,1'-双（甲氧基羰基）-（）、1,1',3-三（甲氧基羰基）-（）和1,1',3,3'-四（甲氧基羰基）二茂铁（）作为氧化还原介质的潜在用途。-中存在的酯基数量和位置对电化学势的影响与哈米特常数之和相关。通过红外和紫外可见光谱电化学方法表明，/ -/氧化还原对在电解条件下化学稳定。酯部分的C=O伸缩振动能量以及-和-的紫外可见吸收能量与酯基数量相关。顺磁H NMR氧化还原滴定实验可获取-的化学位移，并强调了二茂铁/二茂铁鎓氧化还原对快速的电子自交换，这是有机电合成中快速氧化还原介导所必需的。
