Transition-Metal-Substituted Alanes: Synthesis and Spectroscopic Studies and the Structure of (η⁵-C₅H₅)(CO)₂Fe-Al[(CH₂)₃NMe₂](ⁱBu)

Salt elimination between X-Al[(CH₂)₃NMe₂](R) and Y-A1(X)₂(Do) (X, Y = H, Cl, Br; R = Cl, Br, ⁱBu, CH₂^tBu; Do = NMe₃, quinuclidine, THF) and [L(CO)_nM][K] (M = Fe, Ru, Co; L = CO, PMe₃, η⁵-C₅H₅; = 1–3) in THF solution quantitatively gives the transition-metal-substituted alanes L(CO)_nM-Al[(CH₂)₃NMe₂](R) (2a-h) and L(CO)_nM-Al(X)₂(Do) (2k-m). The new compounds were characterized by means of elemental analysis and ¹H, ¹³C, ³¹P, and ²⁷Al NMR, EI-MS, and infrared v(CO) and v(Al-H) data. 2a-m constitute rare examples of nonbridged direct transition-metal-aluminum bonds. Those bonds are rather polarized in a Fe^δ--Al^δ+ fashion and are thus highly reactive toward cleavage in the course of electrophilic or nucleophilic attack. X-ray single crystal data for 2a, (η⁵-C₅H₅)(CO)₂-Fe-Al[(CH₂)₃NMe₂](ⁱBu: monoclinic, P2₁/n, a = 868.0(2) Å, b = 13.468(2) Å, c = 15.213(3)Å, β = 101.79(1)°, V = 1741 ų, Z = 4, R = 0.0536 (R_w = 0.0483). The σ(Fe-Al) bond length is 2.456(1) Å. 2a-d are used as candidates to generate intermetallic Fe/Al and Co/Al thin films by low-pressure MOCVD.