Substitution in Other Mononuclear Complexes

Substitution of CO by an alkyne in the 16-electron complex (1) shown in equation (4) is slow in toluene at 25°C. Under an N2 atmosphere fcobs 

Evidence for a 14-electron [(phen)Mo(CO)2] intermediate was obtained from a study of CO isotopic enrichment of /ac-[(MeCN)-(phen)Mo(CO)3]. Pulsed laser flash photolysis of (2) (M = Cr or Mo) in 1,2-dichloroethane or chlorobenzene produces the five-coordinate (3) which 

The hydrosulfide ligand in [M(CO)5SH] (M = Cr or W) is a good cis labilizer, better than bromide and slightly weaker than acetate. The trans effect for the dissociative ligand substitution shown in equation (8) spans 

Thermal substitution of L in [(MeCp)Mn(CO)2L] is very slow. However, the application of a slight anodic current at room temperature in acetone or MeCN solvent induces rapid ligand substitution according to equation (9) [L = MeCN, py, NHMe2 V = PR3, P(OR)3, AsPh3, SbPh3, 

The ease of the CO substitution shown in equation (10) is in the order cyclopentadienyl indenyl fluorenyl. At 130°C in decalin the second-order rate constants (M s ) are fluorenyl, 1.13 x 10 indenyl, 1.68 x 10 cyclopentadienyl, 10 . These associative reactions are thought to 

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