Xu Hanhua, Lv Ze-Jie, Wei Junnian, Xi Zhenfeng
Beijing National Laboratory for Molecular Sciences (BNLMS), MOE Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing, China.
Dalton Trans. 2023 Aug 22;52(33):11565-11570. doi: 10.1039/d3dt01767b.
A -aryloxide-amidine ligand (HL), integrating phenoxide (PhO) and amidine ligands through methylene linkers, has been synthesized from 2-(aminomethyl)-6-(-butyl)phenol in two steps. Upon reacting the deprotonated HL ligand with group 4 metal chloride MCl, a corresponding (LM-Cl) dimer could be obtained. The coordination modes exhibit variation depending on the radius of the metal ions. In the case of (LTi-Cl), the two ArO arms from the same ligand bond to two different Ti(IV) centers, while in the case of (LZr/Hf-Cl), both ArO arms coordinate with the same metal center. Moreover, the two C-N bonds in the amidinate moiety are localized in (LTi-Cl), whereas they delocalize in (LZr-Cl). Notably, (LHf-Cl) could further react with one equivalent of HfCl, yielding the binuclear metal azide in the presence of KN and LiCl, where the coordination mode of the amidinate moiety changed from the bidentate chelating type to the bimetallic bridging coordination.
一种通过亚甲基连接基整合酚氧基（PhO）和脒配体的芳氧基 - 脒配体（HL），已由2 - （氨基甲基） - 6 - （ - 丁基）苯酚分两步合成。将去质子化的HL配体与第4族金属氯化物MCl反应时，可得到相应的（LM - Cl）二聚体。配位模式根据金属离子的半径而变化。在（LTi - Cl）的情况下，来自同一配体的两个ArO臂与两个不同的Ti（IV）中心键合，而在（LZr/Hf - Cl）的情况下，两个ArO臂都与同一个金属中心配位。此外，脒基部分中的两个C - N键在（LTi - Cl）中是定域的，而在（LZr - Cl）中它们是离域的。值得注意的是，（LHf - Cl）可以与一当量的HfCl进一步反应，在KN和LiCl存在下生成双核金属叠氮化物，其中脒基部分的配位模式从双齿螯合型变为双金属桥连配位。
