Transition metal compounds dative bonding

Dative covalent bonds, or coordinate covalent bonds, are those in which electrons are shared (as in all covalent bonds), but in which both electrons involved in each bond are contributed from the same atom. Such bonds occur in organometallic compounds of transition metals having vacant d orbitals. It is beyond the scope of this book to discuss such bonding in detail the reader needing additional information should refer to works on organometallic compounds.12 The most common organometallic compounds that have dative covalent bonds are carbonyl compounds, which are formed from a transition metal and carbon monoxide, where the metal is usually in the -1, 0, or +1 oxidation state. In these compounds the carbon atom on the carbon monoxide acts as an electron-pair donor ... 

Common oxidation states and /-electron counts for the transition metals are given in Table 25-1. Most /-transition metal ions have vacant d orbitals that can accept shares in electron pairs. Most act as Lewis acids by forming dative bonds with Lewis bases that donate one or more lone pairs of electrons in coordination compounds (coordination com-... 

Mak ef al. employed [Fe(CO)4(Ph2PPy)2] 42 (Ph2PPy = 2-(diphenylphosphino)pyridine) to construct a series of heterobimetallic compounds with an Fe-M dative bond. The iron center in 42 is zero-valent and electron rich and, together with the two pendant pyridyl groups, can be viewed as a structural analog of terpyridine. A rather comprehensive series of metal salts were incorporated, including Cu(i), Ag(i), Zn(ii), Cd(ii), Hg(ii), and other first-row transition elements, such as Fe, Co, and... 

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