Table 1.

Standard enthalpies of complex formation between [Cp*Fe(η⁵‐P₅)] (1) and NHCs/NHO (hereinafter referred to as LB): 1 + LB=1⋅LB. Reaction energies ΔE°₀, standard enthalpies ΔH°₂₉₈, Gibbs energies ΔG°₂₉₈ (kJ mol⁻¹) and standard entropies ΔS°₂₉₈ (J mol⁻¹ K⁻¹) for the considered gas phase processes. B3LYP/6‐31G* level of theory.

LB	ΔE°0	ΔH°298	ΔS°298(g)	ΔG°298(g)	ΔS°298(soln)	ΔG°298(soln)	K298(soln)	T(K=1) [K]
IMe	−47.0	−38.6	−157.2	8.2	−67.2	−18.6	1.82×103	575
IMes	−32.2	−28.1	−192.6	29.3	−102.6	2.5	0.37	274
IDipp	−16.4	−9.8	−198.7	49.4	−108.7	22.6	1.1×10−14	90
ItBu	41.6	46.8	−185.2	102.0	−95.2	75.2	6.6×10−14	–
IDip=CH2	10.4	18.9	−179.8	72.6	−89.8	45.7	9.8×10−9	–