Unexpected antifungal activity of half-sandwich complexes with metal−iodine bonds

Heating of Co2(CO)8 with 1,2,4-triphenylcyclopentadiene followed by addition of I2 gave the half-sandwich complex (C5H2Ph3)Co(CO)I2 (1). Its reaction with 2,2-bipyridine produced the cationic complex [(C5H2Ph3)Co(bipyridine)I]PF6 (2PF6). Both 1 and 2PF6, as well as several similar half-sandwich complexes, e.g. (C5Me5)Co(CO)I2 and (C5H5)Fe(CO)2I, have completely inhibited the growth of six types of phytopathogenic fungi at 30 mg L−1 concentration...