Transition-metal carbon—antimony bonds

Many metal carbonyl clusters have interstitial atoms or groups located in the eenter of the polyhedron. Such interstitial atoms may be a light atom sueh as boron, carbon, or nitrogen a post-transition element such as germanium, tin, or antimony or a transition metal. Interstitial atoms most frequently provide all of their valence electrons as skeletal electrons since all of their valence orbitals are neeessarily internal orbitals because of the location of the interstitial atom in the center of the polyhedron. Exceptions to this rule may occur when some of the valence electrons of the interstitial atom occupy orbitals of symmetries which cannot mix with any of the molecular orbitals arising from the polyhedral skeletal bonding. 

This chapter comprises polynuclear organotin compounds. The derivatives contain at least three different metal atoms arranged in a metal-metal-metal-chain and contain one or more tin-carbon bonds. Tin is always linked to a transition metal. The third metal in the chain is a different transition metal or arsenic, antimony and silicon. All compounds are listed in Table 262. The following synthetic methods are reported. 

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