Palladium complexes bearing calixpyrrole ligands with pendant hydrogen bond donors: Synthesis, structural characterization, electrochemistry and dihydrogen evolution
Palladium complexes bearing calixpyrrole ligands with pendant hydrogen bond donors: Synthesis, structural characterization, electrochemistry and dihydrogen evolution
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带有氢键供体的杯吡咯配体的钯配合物：合成、结构表征、电化学和析氢
DOI：
10.1016/j.poly.2022.116046
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发表时间：
2022
期刊：
影响因子：
2.6
通讯作者：
Sues, Peter E.
中科院分区：
文献类型：
--
作者：
Trowbridge, Logan;Averkiev, Boris;Sues, Peter E.
合成了一系列带有氮基氢键供体 R 的三个杯吡咯配体 (1a-c)，并与钯配位以产生金属配合物 (2a-c)，其中 R = NH2(a)； NHC(O)CH3(b)；或NHC(O)OC(CH3)3(c)。杯吡咯化合物是使用席夫碱反应从 5,5'-二甲酰基-2,2'-二苯基二吡咯甲烷和苯胺前体开始生成的。去质子化的杯吡咯物质随后与钯结合，生成扭曲的方形平面复合物。侧基未与金属配位，Pd-N 距离为 3.36 至 4.79 Å。还探索了钯配合物的电化学性质，与二茂铁/二茂铁 (Fc/Fc+) 相比，2a-c 显示了两次高于 0.0 V 的不可逆氧化，以及与 Fc/Fc+ 相比，在 -0.70 V 以下的两次不可逆还原。有趣的是，游离配体表现出相似的电化学特征，表明氧化还原并非无罪。初步反应性研究表明，钯配合物不会激活小分子，但它们确实在酸存在下催化氢气的析出。 2a-c 的催化起始电压比玻碳电极高约 0.4–0.5 V，并且活性物质可以进行 500 次扫描而活性没有显着变化。发现催化剂本质上是非均相的并且吸附在工作电极上。
A series of three calixpyrrole ligands (1a-c) with pendant nitrogen-based hydrogen bond donors, R, were synthesized and coordinated to palladium to produce metal complexes (2a-c), where R = NH2(a); NHC(O)CH3(b); or NHC(O)OC(CH3)3(c). The calixpyrrole compounds were generated using a Schiff-base reaction starting with 5,5′-diformyl-2,2′-diphenyldipyrromethane and an aniline precursor. The deprotonated calixpyrrole species were subsequently bound to palladium to generate distorted square planar complexes. The pendant groups were not coordinated to the metal with Pd-N distances of 3.36 to 4.79 Å. The electrochemical properties of the palladium complexes were also explored, and2a-cdisplayed two irreversible oxidations above 0.0 V vs ferrocene/ferrocenium (Fc/Fc+), as well as two irreversible reductions below −0.70 V vs Fc/Fc+. Interestingly, the free ligands showed similar electrochemical features, suggesting redox non-innocence. Preliminary reactivity studies indicated the palladium complexes did not activate small molecules, but they did catalyze H2evolution in the presence of acid. The onset of catalysis for2a-cwas approximately 0.4–0.5 V more positive than a glassy carbon electrode, and the active species could undergo 500 scans without significant changes in activity. The catalysts were found to be heterogeneous in nature and adsorbed onto the working electrode.
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影响因子：
12.9
作者：
H. Brown;Stefan Wiese;John A. S. Roberts;R. Bullock;Monte L. Helm
通讯作者：
H. Brown;Stefan Wiese;John A. S. Roberts;R. Bullock;Monte L. Helm
影响因子：
4.9
作者：
Askarizadeh, Elham;Yaghoob, Sahar Bani;Love, Jason B.
通讯作者：
Love, Jason B.
影响因子：
16.6
作者：
Reece SY;Nocera DG
通讯作者：
Nocera DG
影响因子：
4.9
作者：
J. Rosenthal;L. Chng;S. Fried;D. Nocera
通讯作者：
J. Rosenthal;L. Chng;S. Fried;D. Nocera
影响因子：
7.2
作者：
BARBIR, F;VEZIROGLU, TN;PLASS, HJ
通讯作者：
PLASS, HJ