Preparation, Properties, and Reactions, of Metal‐Containing Heterocycles, XCVI . Mono‐, Di‐ and Trinuclear Metallacycloalkanes of the Iron‐Triad

The reaction of the bis(triflates) [F 3 CSO 3‐ (CH) m ‐O 3 SCF 3 ] [m = 5–10, 12, 14, 16 ( 1a – i ) with Na 2 [Os(CO) 4 ] in dimethyl either affords the osmacycloalkanes 2a , 2b and 2f – i ( m = 5, 6, 10, 12, 14, 16), diosmacycloalkanes 3a – i ( m = 5‐10, 12, 14, 16), and triosmacycloalkanes 4a – i ( m = 5–10, 12, 14, 16). The structure of 3f was investigated by an X‐ray structural analysis. This 22‐membered disomacycle crystallizes in the space group P ā with Z = 1. If the unsaturated cis ‐4‐octen‐1,8‐diyl bis(trifluoromethanesulfonate) ( 5 ) is treated with Na 2 [Os(CO) 4 ] the diosmacyclooctadeca‐5,14‐diene 6 is obtained. By treating the bis(triflates) 1a , b with Na 2 [Fe(CO) 4 ] the corresponding ferracycloalkanes are formed only in situ. Insertion of carbon monoxide into the M–C σ bonds leads to the cyclic ketones 7a , d and to the diketone 8d .