Enthalpies of formation of [Mo(η-C5H5)2(SR)2] complexes; R = n-C3H7, i-C3H7, n-C4H9, or t-C4H9

Abstract

The standard enthalpies of formation of the title complexes at 298.15 K have been determined by reaction-solution calorimetry. The results gave ΔHf⊖{[Mo(η-C5H5)2{S(n-C3H7)}2], c}= 4.6 ± 5.3, ΔHf⊖{[Mo(η-C5H5)2{S(i-C3H7)}2], c}= 57.1 ± 5.7, ΔHf⊖{[Mo(η-C5H5)2{S(n-C4H9)}2], c}= 14.0 ± 5.7, and ΔHf⊖{[Mo(η-C5H5)2{S(t-C4H9)}2], c}= 6.9 ± 4.4 kJ mol–1. The metal–sulphur mean bond-enthalpy contributions have been derived as [Mo–S(n-C3H7)]≈ 237, [Mo–S(i-C3H7)]≈ 202, [Mo–S(n-C4H9)]≈ 211, and [Mo–S(t-C4H9)]≈ 193 kJ mol.