Ellen Hancock 200484318 Context Bonds
The Thesis Antithesis and Synthesis of Practice –
approaches that allow facile preparation of organophosphorus compounds avail- able previously only with significant difficulty. Prior to considering synthetic approaches toward C–P bond formation, we review two areas related to the literature of organophosphorus chemistry that are of particular value to those chemists who do not focus primarily on phosphorus. 1.2 Nomenclature of C–P compounds Quite often, we find nonsystematic nomenclature used in the literature dealing with organophosphorus compounds. This results in unnecessary confusion, as systematic nomenclature is easy to use and understand. Nomenclature based on the oxidation state of the phosphorus center eliminates the confusion and helps to promote under- standing of the chemistry as well as to facilitate communication. Table 1.1 shows structures for tricoordinate and tetracoordinate phosphorus compounds related to oxyacids with their English general names. Also noted are the names for simple esters of the parent acids. They are organized based on oxidation state and the number of bonds of the carbon– phosphorus type. At times, confusion arises in noting oxides of primary and sec- ondary phosphines (Figure 1.5). These species participate in equilibria much as the phosphonous and phosphinous acids do and can be named as types of phosphonous and phosphinous acids.
The tetracoordinate phosphorus species related to the oxyacids may be considered to be pentavalent. (For nomenclature purposes we will consider the phosphoryl group, P=O, to be an ordinary double bond.) A variety of tetracoordinate phosphorus compounds that are also clearly tetravalent are common. With four carbon groups (alkyl, aryl, olefinic, or acetylenic) attached to phosphorus, the phosphorus bears a positive charge
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