Photolytic CO-substitution reaction of organoiron thiocarboxylate derivatives CpFe(CO)2SCOR (R=alkyl, aryl) with diphosphines (Ph2P(CH2)nPPh2) (n=1–6): X-ray crystal structure of [CpFe(dppm)SCO(3,5-(NO2)2C6H3)]

The photolytic CO-substitution reaction of the organoiron thiocarboxylate complexes CpFe(CO)2SCOR (R=CH3, 2-CH3C6H4, 2-NO2C6H4, 4-NO2C6H4, 3,5-(NO2)2C6H3) with diphosphines (Ph2P(CH2)nPPh2) [n=1 (dppm), n=2 (dppe), n=3 (dpppr), n=4 (dppb), n=5 (dppp), n=6 (dpph)] at room temperature using 1:2 (metal–ligand) molar ratio afforded exclusively the disubstituted complexes CpFe(Ph2P(CH2)nPPh2)SCOR when n=1, 2 and 3 and the monosubstituted analogs CpFe(CO)(Ph2P(CH2)nPPh2)SCOR when n=4, 5 and 6. This reaction was found to be strongly influenced by the backbone length of the diphosphine ligand, the nature of the R group of the thiocarboxylate moiety and the metal–ligand molar ratios. The crystal structure of CpFe(dppm)SCO(3,5-(NO2)2C6H3) was determined.