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 ΔH_f^⊖{[Mo(η-C₅H₅)₂{S(n-C₃H₇)}₂], c}= 4.6 ± 5.3, ΔH_f^⊖{[Mo(η-C₅H₅)₂{S(i-C₃H₇)}₂], c}= 57.1 ± 5.7, ΔH_f^⊖{[Mo(η-C₅H₅)₂{S(n-C₄H₉)}₂], c}= 14.0 ± 5.7, and ΔH_f^⊖{[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.