The kinetics of the Hg2+-assisted chloride release from some [MCl(RNH2)5]2+ complexes (M = Co, Cr)
作者:Jirong Wang、Donald A. House
DOI:10.1016/0020-1693(94)04390-h
日期:1995.5
Activation parameters associated with the Hg2+-assisted chloride release reaction in 50:50 dioxane:aqueous HClO4(I=0.5 M) from [MCI(RNH(2))(5)](2+) at 25 degrees C in the order (k(Hg), M(-1)S(-1);Delta H*,kJ mol(-1);Delta S*,J K-1 mol(-1) are M=Cr,R=H:5.45X10(-2),74.7,-18;M=Cr,R=Me:1.78x10(-3),70.0,-32;M=Cr,R=Et:1.19x10(-3),86.8,-9;M=Cr,R=nPr:7.06x10(-4),96.3,+17;M=Cr,R=nBu:5.30X10(-4),98.0,+21;M=Co,R=H:8.74x10(-2),70.3,-37;M=Co,R=Me:2.40,74.0,+11;M=Co,R=Et:4.95,69.0,0;M=Co,R=nPr:2.59,69.3,-5;M=Co,R=nBu:2.15,70.2,-3. Similar data in aqueous HClO4 (I=1.0 M) are M=Cr,R=H:9.84x10(-2),64.6,-27;M=Cr,R=Me:2.15x10(-3),93.2,+16.5M=Co,R=H:1.40x10(-1),65.1,-42; M=Co,R=Me:5.00,70.4,+5. The trends in activation entropy would rank MCl(RNH(2))(5)](2+) (R not equal H) at essentially the same position on an interchange mechanistic scale, independent of M, and more associatively restricting than [MCl(NH3)(5)](2+).