Synthesis and Electrochemical Behavior of Metal Carbonyl Isocyanoferrocene Compounds [M(CO)6-n(C≡NFc)n] (M=Cr, Mo, W; n=1, 2, 3)

The synthesis of [M(CO)(6-n)(C equivalent to NFc)(n)] (n=1: M=Cr, 3 a; M=Mo, 3 b; M=W, 3 c. n=2: M=Mo, 5. n=3: M=Mo, 6. Fc=Fe(eta(5)-C5H4)(eta(5)-C5H5)) by the reaction of [M(CO)(5)(thf)] (M=Cr, 1 a; M=Mo, 1 b; M=W 1 c) (synthesis of 3 a-c), [Mo(CO)(4)(nbd)] (4) (synthesis of 5) or [Mo(CO)(6)] (synthesis of 6) with FcN equivalent to C (2) is discussed. IR studies confirm the formation of cis-[Mo(CO)(4)(C equivalent to NFc)(2)] (5) and mer-[Mo(CO)(3)(C equivalent to NFc)(3)] (6). The electrochemical behavior of 2, 3 a-c, 5 and 6 is reported. Compound 2 shows a reversible Fc redox event at E degrees(1)'=355 mV (Delta E-p=60 mV). Upon complexation of 2 to M(CO)(5) this wave is slightly shifted to E degrees '=335 (3 a), 345 (3 b) and 340 mV (3 c) showing that in 3 a-c the FcN equivalent to C ligand is more easy to oxidize. The substitution of further CO ligands in 3 b by FcN equivalent to C as characteristic for 5 and 6 influences the respective redox events insignificantly. Reversible oxidation of Cr occurs at 1045 mV (3 a) (Delta E-p=60 mV), while for 3 b,c (3 b: 1170 mV, 3 c: 1290 mV) irreversible oxidations were observed. In addition, in situ spectroelectrochemical IR studies were carried out on 3 a-c. The results were further confirmed by DFT calculations.

Automated summary

This study discussed the synthesis of [M(CO)(6-n)(C equivalent to NFc)(n)] (n=1: M=Cr, 3 a; M=Mo, 3 b; M=W, 3 c. n=2: M=Mo, 5. n=3: M=Mo, 6. Fc=Fe(eta(5)-C5H4)(eta(5)-C5H5)) through the reaction with [FcN equivalent to C (2)]. The formation of cis-[Mo(CO)(4)(C equivalent to NFc)(2)] and mer-[Mo(CO)(3)(C equivalent to NFc)(3)] was confirmed by IR studies. The electrochemical behavior of 2, 3 a-c, 5 and 6 was reported, and in situ spectroelectrochemical IR studies were conducted on 3 a-c. The results were further confirmed by DFT calculations.