TY - JOUR
T1 - Low-Temperature Neutron Diffraction Study of HMn2Re(CO)14 and Studies of a Metal-Metal Exchange Equilibrium That Converts HMn2Re(CO)14 into HMnRe2(CO)14
AU - Bullock, R. Morris
AU - Brammer, Lee
AU - Schultz, Arthur J.
AU - Albinati, Alberto
AU - Koetzle, Thomas F.
PY - 1992/6/1
Y1 - 1992/6/1
N2 - The crystal and molecular structure of (CO)5Re(μ-H)Mn(CO)4Mn(CO)5, prepared from reaction of Mn2- (CO)9(η1-tolualdehyde) with HRe(CO)5, has been determined from neutron diffraction measurements at 15 K: unit-cell constants, a = 9.145 (1) Å, b = 15.557 (3) Å, c = 14.040 (3) Å, β = 106.60 (2)°, monoclinic, space group P21/n, Z = 4, V = 1914.2 (6) Å3. R(F2) = 0.110 for 4859 reflections with F02 ≥ 3σ(F02) and (sin θ/λ)max = 1.054 Å-1. The Re-H distance (1.827 (4) Å) is longer than the Mn-H distance (1.719 (5) Å). Spectroscopic and crystallographic data indicate that a small amount (~9%) of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 has cocrystallized with the major component. Further evidence for the identity of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 comes from an independent synthesis by a known route. A mechanism is proposed that accounts for the formation of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 from the reaction of (CO)5Re(μ-H)Mn(CO)4Mn(CO)5 with HRe(CO)5. The equilibrium constant for the metal-metal exchange equilibrium, (CO)5Re(μ-H)Mn(CO)4Mn(CO)5 + HRe(CO)5 ⇌ (CO)5Re(μ-H)Mn(CO)4Re(CO)5 + HMn(CO)5, has been determined; Keq= 1.00 ± 0.05 at 22 °C in C6D6.
AB - The crystal and molecular structure of (CO)5Re(μ-H)Mn(CO)4Mn(CO)5, prepared from reaction of Mn2- (CO)9(η1-tolualdehyde) with HRe(CO)5, has been determined from neutron diffraction measurements at 15 K: unit-cell constants, a = 9.145 (1) Å, b = 15.557 (3) Å, c = 14.040 (3) Å, β = 106.60 (2)°, monoclinic, space group P21/n, Z = 4, V = 1914.2 (6) Å3. R(F2) = 0.110 for 4859 reflections with F02 ≥ 3σ(F02) and (sin θ/λ)max = 1.054 Å-1. The Re-H distance (1.827 (4) Å) is longer than the Mn-H distance (1.719 (5) Å). Spectroscopic and crystallographic data indicate that a small amount (~9%) of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 has cocrystallized with the major component. Further evidence for the identity of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 comes from an independent synthesis by a known route. A mechanism is proposed that accounts for the formation of (CO)5Re(μ-H)Mn(CO)4Re(CO)5 from the reaction of (CO)5Re(μ-H)Mn(CO)4Mn(CO)5 with HRe(CO)5. The equilibrium constant for the metal-metal exchange equilibrium, (CO)5Re(μ-H)Mn(CO)4Mn(CO)5 + HRe(CO)5 ⇌ (CO)5Re(μ-H)Mn(CO)4Re(CO)5 + HMn(CO)5, has been determined; Keq= 1.00 ± 0.05 at 22 °C in C6D6.
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U2 - 10.1021/ja00039a025
DO - 10.1021/ja00039a025
M3 - Article
AN - SCOPUS:0002744983
VL - 114
SP - 5125
EP - 5130
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 13
ER -