Synthesis, Characterization and Reactivity of the Tricarbonyl(formylcycloheptatrienyl)iron‐Anion [( η 3 ‐C 7 H 6 CHO)Fe(CO) 3 ] −

Deprotonation of the readily available organometallic aldehyde derivative [( η 4 ‐C 7 H 7 CHO)Fe(CO) 3 ] ( 2 ) with NaN(SiMe 3 ) 2 in benzene solution at ambient temperature afforded the anionic formylcycloheptatrienyl complex Na[( η 3 ‐C 7 H 6 CHO)Fe(CO) 3 ] ( 3 ). The anion is fluxional in solution and displays a unique ambident reactivity towards electrophiles (MeI, Me 3 SiCl). New substituted [( η 4 ‐RC 7 H 6 CHO)Fe(CO) 3 ] and [( η 4 ‐heptafulvene)Fe(CO) 3 ] complexes have been identified as the products. Treatment of 3 with 0.5 equivalents of dimeric [(COD)RhCl] 2 (COD = 1,5‐cyclooctadiene) afforded the functionalized Fe‐Rh cycloheptatrienyl complex [( μ ‐C 7 H 6 CHO)(CO) 3 FeRh(COD)] ( 7 ) in up to 86 % yield. Carbonylation of 7 under an atmosphere of CO led to facile conversion to the heterobimetallic pentacarbonyl derivative [( μ ‐C 7 H 6 CHO)(CO) 3 FeRh(CO) 2 ] ( 8 ), which is also accessible in lower yield from the direct reaction of 3 with [Rh(CO) 2 Cl] 2 .