Disproportionation of aquachromyl(IV) ion by hydrogen abstraction from coordinated water

被引:23
作者
Nemes, A [1 ]
Bakac, A [1 ]
机构
[1] Iowa State Univ, Ames Lab, Ames, IA 50011 USA
关键词
D O I
10.1021/ic0013577
中图分类号
O61 [无机化学];
学科分类号
070301 ; 081704 ;
摘要
In aqueous solutions, the aquachromyl(IV) ion, CraqO2+, disproportionates to Cr-aq(3+) and HCrO4-. The reaction exhibits second-order kinetics with an inverse [H+] dependence, -d[CraqO2+]/dt = 38.8[CraqO2+](2)[H+](-1) at 25 degreesC. The combination of the rate law and substantial kinetic isotope effect, k(H)/k(D) = 6.9, suggests a mechanism whereby a hydrogen atom is abstracted from a coordinated molecule of water or hydroxo group within a singly deprotonated transition state. The buildup of chromate is more complicated and somewhat slower than the loss of chromyl, suggesting the involvement of intermediates.
引用
收藏
页码:2720 / 2724
页数:5
相关论文
共 42 条
[21]   A TRACER STUDY OF CHROMIUM(2)-CHROMIUM(6) REACTION [J].
HEGEDUS, LS ;
HAIM, A .
INORGANIC CHEMISTRY, 1967, 6 (04) :664-&
[22]   A metalloradical mechanism for the generation of oxygen from water in photosynthesis [J].
Hoganson, CW ;
Babcock, GT .
SCIENCE, 1997, 277 (5334) :1953-1956
[23]   STOICHIOMETRIC STUDY OF CHROMIUM(II)-CHROMIUM(VI) REACTION IN ACIDIC AQUEOUS CHLORIDE MEDIA [J].
KENNY, JC ;
CARLYLE, DW .
INORGANIC CHEMISTRY, 1973, 12 (08) :1952-1954
[24]   THE INTERACTION OF CHROMIUM(III) AND CHROMIUM(VI) IN ACIDIC SOLUTION [J].
KING, EL ;
NEPTUNE, JA .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1955, 77 (12) :3186-3189
[25]  
KLANING UK, 1977, J CHEM SOC FARAD T 1, V73, P434, DOI 10.1039/f19777300434
[26]   LOW-FREQUENCY EPR STUDY OF CHROMIUM(V) FORMATION FROM CHROMIUM(VI) IN LIVING PLANTS [J].
LIU, KJ ;
JIANG, JJ ;
SHI, XL ;
GABRYS, H ;
WALCZAK, T ;
SWARTZ, HM .
BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, 1995, 206 (03) :829-834
[27]  
LIU KJ, 1995, ARCH BIOCHEM BIOPHYS, V323, P33
[28]   CHROMIUM(V) COORDINATION CHEMISTRY [J].
MITEWA, M ;
BONTCHEV, PR .
COORDINATION CHEMISTRY REVIEWS, 1985, 61 (JAN) :241-272
[29]  
NEMES A, 2001, INORG CHEM, V40
[30]  
NEWTON TW, 1962, INORG CHEM, V2, P368