Manganese complexes butadiene

Condensation of manganese and butadiene followed by addition of CO at -196°C gives a very low yield of Mn(C4H6)2CO (40). However, iron reacts quite efficiently and affords a red-brown complex that decomposes at about -5°C in the solid state ... 

Bis(butadiene) complexes, with tantalum, 5, 173 Bis(z-butanethiolato) complexes, with bis-Cp Ti(IV), 4, 601 Bis(calixarene) complexes, as organic molecule hosts, 12, 799 Bis(carbene) complexes with gold(I), 2, 287-288 with manganese, 5, 780, 5, 826 with mercury, 2, 429 with palladium, 8, 230 with silver , 2, 206... 

The molecular structure (362) of the complex (C4Hg)[Fe(CO)4]2 is similar to that of its manganese analog (45). It consists of a planar (tows-1,3-butadiene moiety bonded in such a way to two Fe(CO)4 groups that each of the double bonds occupies an equatorial position in a different trigonal bipyramid (70). 

In the butadiene complexes of vanadium, chromium, molybdenum, tungsten and manganese (Table 7) the butadiene has replaced two carbonyl groups and presumably bonds to these two co-ordination positions of the metal. 

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