Singly-bonded Compounds

It may also be represented as a hexagon with a circle in the middle. The circle is a symbol of the n cloud encircling the benzene ring. The delocalized electrons associated with the benzene ring impart very special properties to aromatic hydrocarbons. They have chemical properties of single-bond compounds such as paraffin hydrocarbons and doublebond compounds such as olefins, as well as many properties of their own. 

The single-bond compounds between Si, Ge, and Sn and chalcogens (S, Se, Te) are reactive and used as synthetic intermediates in the synthesis of organic compounds, organochalcogen compounds, organo-silicon, -germanium and -tin compounds, and transition metal-chalcogen complexes and clusters. 

Double-bond compounds between heavier group 14 and 16 elements (heavy ketones) undergo ready addition reactions with various reagents to give the corresponding single-bond compounds. The details of the reactivities are described in the next section (Schemes 20 and 21). 

Single bonded compounds R3C-H Alkane R3SDH Silane... 

Complex 177 contains both MoVI and Mov ions, with the latter linked in pairs by metal-metal single bonds. Compound 178 involves a single-valent mo-lybdenum(VI) octamolybdenum species and is photosensitive. 

Infrared spectral data for sulfur-containing compounds are covered in this section. Included here are single-bonded compounds (mercaptans or thiols and sulfides). Double-bonded S=0 compounds are also included in this section. 

Hydrocarbon compounds with double bonds can also be made into radicals. In order to have a double bond, there must first be at least two carbons there are no double-bonded radicals with only one carbon. Only two double-bonded hydrocarbon radicals are important here. They are two-carbon and three-carbon radicals with double bonds between the carbons. Since the prefixes for two and three carbons have been used up in the single-bonded compounds, the names for these double-bonded radicals are different from the others a two-carbon compound with a double bond is called vinyl, which is actually a radical of ethene or ethylene the three-carbon compound with one double bond is called acryl, which is a radical of propene or propylene. The structures for the vinyl and acryl radicals are shown in Figure 5.45. 

The Pb-Pb derivatives are by far the least numerous of the Group 14 singly bonded compounds due to the inherent wetikness of the metal-metal bonding. Chain compounds are limited to up to four linked lead units. The hexaorganodilead compounds represent the most studied class. Synthetic routes to access RjPb-PbRj include Wurtz coupling of triorganolead halides as well as reaction of lead(II) chloride with Grignards (Eq. (14.15)) [54]. 

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