Generation and Tunable Cyclization of Formamidinate Ligands in Carbonyl Complexes of Mn(I): An Experimental and Theoretical Study
Generation and Tunable Cyclization of Formamidinate Ligands in Carbonyl Complexes of Mn(I): An Experimental and Theoretical Study
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Mn(I) 羰基配合物中甲脒配体的生成和可调环化：实验和理论研究
DOI：
10.1021/acs.organomet.8b00898
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发表时间：
2019
期刊：
影响因子：
2.8
通讯作者：
Juan F. Van der Maelen
中科院分区：
文献类型：
--
作者：
J. Ruiz;Daniel Sol;Lucía García;María A. Mateo;M. Vivanco;Juan F. Van der Maelen
在式fac-[Mn（RN <$C（H）NHR）（bipy）（CO）3]+的N，N′-二芳基甲脒络合物中氮原子上取代基的细微变化（1a，R =苯基; 1b，R = 4-二甲基氨基苯基）在去质子化时产生单齿甲脒络合物fac-[Mn（PhN = C（H）NPh）（bipy）（CO）3]（2a）或金属丙环络合物3b，其特征在于由亲核攻击邻位羰基配体而产生的氨基甲酰基残基。当使用N-芳基-N '-烷基-甲脒以及N，N'-二烷基甲脒时，也形成3型络合物。分子中原子的量子理论计算表明，在甲脒基的未配位氮原子和2a中的羰基配体之间存在主要为非共价静电型的弱键临界点，这似乎是在形成金属环配合物3之前的可分离的中间物种。
A subtle change in the substituents at the nitrogen atoms in the N,N′-diarylformamidine complexes of formula fac-[Mn(RN═C(H)NHR)(bipy)(CO)3]+ (1a, R = phenyl; 1b, R = 4-dimethylaminophenyl) produces, upon deprotonation, either the monodentate formamidinate complex fac-[Mn(PhN═C(H)NPh)(bipy)(CO)3] (2a) or metallacylic complex 3b, which features a carbamoyl residue arising from nucleophilic attack to a vicinal carbonyl ligand. Complexes type 3 are also formed when using N-aryl-N′-alkyl-formamidines as well as N,N′-dialkylformamidines. Quantum Theory of Atoms in Molecules computations show the existence of a weak bond critical point of mainly noncovalent electrostatic type between the uncoordinated nitrogen atom of the formamidinate and a carbonyl ligand in 2a, which appears to be an isolable intermediate species that precedes the formation of metallacyclic complexes 3.