Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Low-temperature neutron diffraction study of HMn{sub 2}Re(CO){sub 14} and studies of a metal-metal exchange equilibrium that converts HMn{sub 2}Re(CO){sub 14} into HMnRe{sub 2}(CO){sub 14}

Journal Article · · Journal of the American Chemical Society
;  [1];  [2]
  1. Brookhaven National Lab., Upton, NY (United States)
  2. Argonne National Lab., IL (United States); and others

The crystal and molecular structure of (CO){sub 5}Re({mu}-H)Mn(CO){sub 4}Mn(CO){sub 5}, prepared from reaction of Mn{sub 2-} (CO){sub 9}({eta}{sup 1}-tolualdehyde) with HRe(CO){sub 5}, has been determined from neutron diffraction measurements at 15K: unit-cell constants, a = 9.145 (1) {angstrom}, b = 15.557 (3) {angstrom}, c = 14.040 (3) {angstrom}, {beta} = 106.60 (2){degrees}, monoclinic, space group P2{sub 1}/n, Z = 4, V = 1914.2 (6) {angstrom}{sup 3}. R(F{sup 2}) = 0.110 for 4859 reflections with F{sub 0}{sup 2}{ge}3{sigma}(F{sub 0}{sup 2}) and (sin {theta}/{lambda}){sub max} = 1.054 {angstrom}{sup -1}. The Re-H distance (1.827 (4) {angstrom}) is longer than the Mn-H distance (1.719 (5) {angstrom}). Spectroscopic and crystallographic data indicate that a small amount ({approximately}9%) of (CO){sub 5}Re({mu}-H)Mn(CO){sub 4}Re(CO){sub 5} has cocrystallized with the major component. Further evidence for the identity of (CO){sub 5}Re({mu}-H)Mn(CO){sub 4}Re(CO){sub 5} comes from an independent synthesis by a known route. A mechanism if proposed that accounts for the formation of (CO){sub 5}Re({mu}-H)Mn(CO){sub 5} from the reaction of (CO){sub 5}Re({mu}-H)Mn(CO){sub 4}Mn(CO){sub 5} with HRe(CO){sub 5}. The equilibrium constant for the metal-metal exchange equilibrium, (CO){sub 5}Re({mu}-H) Mn(CO){sub 4}Mn(CO){sub 5}+HRe(CO){sub 5} = (CO){sub 5}Re({mu}-H)Mn(CO){sub 5} + HMn(CO){sub 5}, has been determined; K{sub eq} = 1.00 {+-} 0.05 at 22 {degrees}C in C{sub 6}D{sub 6}. 36 refs., 3 figs., 3 tabs.

Research Organization:
Brookhaven National Laboratory (BNL), Upton, NY
DOE Contract Number:
AC02-76CH00016; W-31109-ENG-38
OSTI ID:
284989
Journal Information:
Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 13 Vol. 114; ISSN JACSAT; ISSN 0002-7863
Country of Publication:
United States
Language:
English