Nitrogen orbital hybridization

An orbital hybridization description of bonding m methylamme is shown m Figure 22 2 Nitrogen and carbon are both sp hybridized and are joined by a ct bond The unshared electron pair on nitrogen occupies an sp hybridized orbital This lone parr IS involved m reactions m which amines act as bases or nucleophiles The graphic that opened this chapter is an electrostatic potential map that clearly shows the concentration of electron density at nitrogen m methylamme... 

The valence-bond concept of orbital hybridization described in the previous four sections is not limited to carbon compounds. Covalent bonds formed by-other elements can also be described using hybrid orbitals. Look, for instance, at the nitrogen atom in methylamine, CH3NH2, an organic derivative of ammonia (NH3) and the substance responsible for the odor of rotting fish. 

The geometry about a ligand nitrogen coordinated to a metal ion is assumed to be planar with bond directions defined in Fig. 28. The hybridizations of the nitrogen orbitals for different angles between the bonds in the plane can be written as ... 

The nitrene nitrogen atom of imidogen is sp hybridized. Both the NH bond and the sigma lone pair of electrons use nitrogen orbitals that are rich in 2s character. 

Using notions of complexing, draw an ammonium ion. What atom is the donor in the given ion and what atom is the acceptor of electrons What is the coordination number of nitrogen in an ammonium ion What is the geometric model of an ammonium ion What type of orbital hybridization occurs when it forms ... 

Owing to the presence of the molecular 7r system, the nitrogen sp2 hybridized orbitals are not quite similar to those of amides and the following set of functions is usually employed to describe a pyridino nitrogen orbital 47 ... 

In contrast to aromatic amines, the amide group is completely planar (p. 165) with the nitrogen sp2 hybridized and its lone pair in the p orbital, thereby enabling it to overlap effectively with the carbonyl group. 

In the case of ammonia, the five valence electrons surrounding nitrogen— two electrons occupying the outermost 2s orbital and three electrons in three 2p orbitals— hybridize to form four sp orbitals that, if equal, would separate themselves in three dimensional space by pointing at the comers of a tetrahedron. One of these orbitals, however, contains the lone electron pair, and the three remaining sp orbitals make additional space available by pointing at the comers of a pyramid with a triangular base. 

If the orbital on the nitrogen is forced out of this orientation (by substitution on C-2 and C-6, for example), the electrons are no longer shared with the ring. The nitrogen is hybridized sp (no longer any reason to be sp ), and the electron pair is readily available for bonding increased basicity. 

An orbital hybridization description of bonding in methylamine is shown in Figure 22.2. Nitrogen and carbon are both yp -hybridized and are joined by a ct bond. The... 

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