TY - JOUR
T1 - Diverse roles of hydrogen in rhenium carbonyl chemistry
T2 - Hydrides, dihydrogen complexes, and a formyl derivative
AU - Li, Nan
AU - Xie, Yaoming
AU - King, R. Bruce
AU - Schaefer, Henry F.
PY - 2010/11/4
Y1 - 2010/11/4
N2 - Rhenium carbonyl hydride chemistry dates back to the 1959 synthesis of HRe(CO)5 by Hieber and Braun. The binuclear H2Re 2(CO)8 was subsequently synthesized as a stable compound with a central Re2(μ-H)2 unit analogous to the B 2(μ-H)2 unit in diborane. The complete series of HRe(CO)n (n = 5, 4, 3) and H2Re2(CO) n (n = 9, 8, 7, 6) derivatives have now been investigated by density functional theory. In contrast to the corresponding manganese derivatives, all of the triplet rhenium structures are found to lie at relatively high energies compared with the corresponding singlet structures consistent with the higher ligand field splitting of rhenium relative to manganese. The lowest energy HRe(CO)5 structure is the expected octahedral structure. Low-energy structures for HRe(CO)n (n = 4, 3) are singlet structures derived from the octahedral HRe(CO)5 structure by removal of one or two carbonyl groups. For H2Re2(CO)9 a structure HRe2(CO)9(μ-H), with one terminal and one bridging hydrogen atom, lies within 3 kcal/mol of the structure Re2(CO) 9(η2-H2), similar to that of Re 2(CO)10. For H2Re2(CO)n (n = 8, 7, 6) the only low-energy structures are doubly bridged singlet Re 2(μ-H)2(CO)n structures. Higher energy dihydrogen complex structures are also found.
AB - Rhenium carbonyl hydride chemistry dates back to the 1959 synthesis of HRe(CO)5 by Hieber and Braun. The binuclear H2Re 2(CO)8 was subsequently synthesized as a stable compound with a central Re2(μ-H)2 unit analogous to the B 2(μ-H)2 unit in diborane. The complete series of HRe(CO)n (n = 5, 4, 3) and H2Re2(CO) n (n = 9, 8, 7, 6) derivatives have now been investigated by density functional theory. In contrast to the corresponding manganese derivatives, all of the triplet rhenium structures are found to lie at relatively high energies compared with the corresponding singlet structures consistent with the higher ligand field splitting of rhenium relative to manganese. The lowest energy HRe(CO)5 structure is the expected octahedral structure. Low-energy structures for HRe(CO)n (n = 4, 3) are singlet structures derived from the octahedral HRe(CO)5 structure by removal of one or two carbonyl groups. For H2Re2(CO)9 a structure HRe2(CO)9(μ-H), with one terminal and one bridging hydrogen atom, lies within 3 kcal/mol of the structure Re2(CO) 9(η2-H2), similar to that of Re 2(CO)10. For H2Re2(CO)n (n = 8, 7, 6) the only low-energy structures are doubly bridged singlet Re 2(μ-H)2(CO)n structures. Higher energy dihydrogen complex structures are also found.
UR - http://www.scopus.com/inward/record.url?scp=78049497764&partnerID=8YFLogxK
U2 - 10.1021/jp103267v
DO - 10.1021/jp103267v
M3 - Article
C2 - 20942474
AN - SCOPUS:78049497764
SN - 1089-5639
VL - 114
SP - 11670
EP - 11680
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 43
ER -