Conjugate base, definition bonds

The Br0nsted-Lowry definition states that an acid is a proton donor (Chapter 2, Section 2.1), but the proton does not fly off. In fact, the acidic proton in A H is pulled off by the base, and this reaction leads to cleavage of the covalent bond between A and H with transfer of those two electrons from the A-H bond to A. This reaction generates the electron-rich A (the conjugate base). Therefore, the acid-base reaction shown is simply a chemical reaction in which the electron-rich base donates two electrons to the electron-poor proton, forming a new covalent bond and breaking the covalent bond between A-H with transfer of those two electrons to A. 

Since conjugation and homoconjugation are parallel concepts, it is logical to base a chemically relevant definition of homoconjugation on the concept of bond (electron) delocalization ... 

If one could change the position of 1 double bond in linoleic acid, c9,cl2-18 2, the resulting compound, by convenient definition, is conjugated linoleic acid or CLA. This can be accomplished with heat and KOH (22). Heating a methylene-interrupted FA with a base will enable the movement of a double bond with a change in the geometry of the double bond that shifts from cis to trans (>95% typical for 160-170°C with KOH) thus, linoleic acid, c9,cl2-18 2 is converted primarily to z9,fll-18 2 and rl0,cl2-18 2. If linolaidic acid, r9,fl2-18 2, is treated similarly with base, it is converted primarily to iS,c and cl0,rl2-18 2 with >70% yield. The synthasis... 

There is one important distinction. When a base such as "NH2 donates electrons to the electron-deficient proton of HCl, for example, a conjugate acid is formed H-NH2, with the new covalent N-H bond. This reaction breaks the H-Cl bond, generating Cl. There are two products because the acid-base reaction breaks the bond between the proton and the other atom and forms the conjugate acid. When a Lewis base such as ammonia reacts with a Lewis acid such as BFg, however, a dative bond is formed to give the Lewis acid-Lewis base complexes (an ate complex), so there is one product rather than two. This statement is an overgeneralization, but it offers a useful starting point to allow the two definitions to be distinguished from one another. These points will be emphasized in this section. 

---