Thermodynamic and Kinetic Study of Cleavage of the N–O Bond of N-Oxides by a Vanadium(III) Complex: Enhanced Oxygen Atom Transfer Reaction Rates for Adducts of Nitrous Oxide and Mesityl Nitrile Oxide
作者:Taryn D. Palluccio、Elena V. Rybak-Akimova、Subhojit Majumdar、Xiaochen Cai、Megan Chui、Manuel Temprado、Jared S. Silvia、Anthony F. Cozzolino、Daniel Tofan、Alexandra Velian、Christopher C. Cummins、Burjor Captain、Carl D. Hoff
DOI:10.1021/ja405395z
日期:2013.7.31
Thermodynamic, kinetic, and computational studies are reported for oxygen atom transfer (OAT) to the complex V(N[t-Bu]Ar)3 (Ar = 3,5-C6H3Me2, 1) from compounds containing N-O bonds with a range of BDEs spanning nearly 100 kcal mol(-1): PhNO (108) > SIPr/MesCNO (75) > PyO (63) > IPr/N2O (62) > MesCNO (53) > N2O (40) > dbabhNO (10) (Mes = mesityl; SIPr = 1,3-bis(diisopropyl)phenylimidazolin-2-ylidene;
热力学、动力学和计算研究报告了氧原子转移 (OAT) 到复合物 V(N[t-Bu]Ar)3 (Ar = 3,5-C6H3Me2, 1) 从含有 NO 键的化合物中跨越近 100 kcal mol(-1) 的 BDE:PhNO (108) > SIPr/MesCNO (75) > PyO (63) > IPr/N2O (62) > MesCNO (53) > N2O (40) > dbabhNO (10) ( Mes = 甲基;SIPr = 1,3-双(二异丙基)苯基咪唑啉-2-亚基;Py = 吡啶;IPr = 1,3-双(二异丙基)苯基咪唑-2-亚基;dbabh = 2,3:5,6-二苯并-7-氮杂双环[2.2.1]庚-2,5-二烯)。OAT 反应的停流动力学研究表明,一系列动力学行为受 O 供体的配位模式和强度及其原子转移的难易程度的影响。根据所涉及的速率常数的大小,观察到四类动力学行为:(I)