Carbene complexes of FeII prepared from a precursor complex containing a remote nucleophilic heteroatom

Abstract The complex [(η 5 -C 5 H 5 )Fe(CO) 2 Cl] reacts with isothiazol-5-yl-lithium to form [(η 5 -C 5 H 5 )Fe(CO) 2 ( CCHCHNS )] ( 1 ). Treatment of 1 with CF 3 SO 3 H or CF 3 SO 3 Me gives the cationic organo(thio)- carbene complexes [(η 5 -C 5 H 5 )Fe(CO) 2 ( CCHCHN(R)S )][SO 3 CF 3 ] (R = H( 2 ); Me( 3 )). Determination of the crystal structure of complex 3 has revealed an Fe-carbene carbon bond length of 1.952(3) A.