Understanding reaction mechanisms of metal-free dinitrogen activation by methyleneboranes

作     者：Jie Zeng Jiaying Su Feiying You Jun Zhu Jie Zeng;Jiaying Su;Feiying You;Jun Zhu

作者机构：State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China 

出 版 物：《Chinese Chemical Letters》 (中国化学快报（英文版）)

年 卷 期：2023年第34卷第2期

页      面：210-213页

核心收录：

学科分类：07[理学] 070304[理学-物理化学(含∶化学物理)] 0703[理学-化学] 

基　　金：Financial support by the National Science Foundation of China (No. 22073079) the Top-Notch Young Talents Program of China is gratefully acknowledged。 

主　　题：Dinitrogen activation Methyleneborane NHC-stabilized borylene Reaction mechanism Singlet–triplet gap 

摘      要：Dinitrogen activation under mild conditions is important but extremely challenging due to the inert nature of the N≡N triple bond evidenced by high bond dissociation energy(945 k J/mol) and large HOMOLUMO gap(10.8 e V). In comparison with largely developed transition metal systems, the reported main group species on dinitrogen activation are rare. Here, we carry out density functional theory calculations on methyleneboranes to understand the reaction mechanisms of their dinitrogen activation. It is found that the methyleneboranes without any substituent at the boron atom performs best on dinitrogen activation, which could be contributed to its small singlet-triplet gap. In addition, strong correlations are achieved on dinitrogen activation between the singlet-triplet energy gap and the reaction energies for the formation of the end-on products as well as the side-on ones. The principal interacting orbital analysis suggests that methyleneboranes can mimic transition metals to cleave the N≡N triple bond. Our findings could be helpful for experimental chemists aiming at dinitrogen activation by main group species.