Synthesis of some ring-substituted [1]ferrocenophanes and the structure of four representative examples

Article abstract of DOI:10.1021/om00073a024

The reaction of 1,1′-dilithioferrocenes (η⁵-C₅H₄Li)Fe(η⁵-C ₅H₃R¹Li) [R¹ = H, CHMeNMe₂, or CH-(CHMe₂)NMe₂] with Cl₂PPh, I₂AsPh, and Cl₂P-t-Bu [X₂ER²] affords the appropriate [1]ferrocenophanes (η⁵-C₅H₄)Fe(η⁵-C ₅H₃R¹ER²). The crystal structures of four such complexes have been determined: R¹ = H, E = P, R² = Ph; Pbca, a = 7.3427 (8) A?, b = 27.078 (4) A?, c = 12.682 (2) A?, Z = 8, R = 0.045 for 1544 reflections; R¹ = H, E = P, R² = t-Bu; P2₁/n, a = 6.1007 (5) A?, b = 20.1851 (8) A?, c = 10.2303 (9) A?, β = 93.284 (4)°, Z = 4, R = 0.036 for 2427 reflections; R¹ = CH(CHMe₂)NMe₂, E = P, R² = Ph; P2₁/c, a = 8.2775 (9) A?, b = 15.4055 (8), c = 15.7558 (19) A?, β = 103.908 (5)°, Z = 4, R = 0.030 for 2730 reflections; R¹ = CHMeNMe₂, E = As, R² = Ph; P1, a = 9.0873 (8) A?, b = 10.2776 (7) A?, c = 11.0240 (8) A?, α = 65.974 (7)°, β = 66.451 (6)°, γ = 76.959 (6)°, Z = 2, R = 0.024 for 3404 reflections. In the three phosphorus-bridged [1]ferrocenophanes, the mean tilt of the cyclopentadienyl rings is 27.0 (1)°, and the mean bridgehead angle at phosphorus is 90.8 (4)°. The corresponding parameters for the arsenic derivatives are 22.9 and 87.90 (7)°, respectively. The mean Fe- (cyclopentadienyl ring centroid) distance for all four molecules is 1.636 (6) A?.