Alkyl halides classification

CLASSIFICATION OF REACTIONS BY TYPE OF COMPOUND SYNTHESIZED 16-47 Reaction of phosphines with Michael alkenes or with alkyl halides... 

In addition to methyl iodide the term iodomethane can be used. For purposes of classification the alkyl halides are to be regarded as esters. The halogen does not ionize and its mobility increases in the order chloride, bromide, iodide. 

Alcohols and alkyl halides are classified as primary, secondary, or tertiary according to the classification of the carbon that bears the functional group (Section 2.10). Thus, primary alcohols and primary alkyl halides are compounds of the type RCH2G (where G is the fnnctional group), secondary alcohols and secondary alkyl halides are compounds of the type R2CHG, and tertiary alcohols and tertiary alkyl halides are compounds of the type R3CG. 

The mechanisms of the usual organic reactions are now clearly established, and the reactions are classified as ionic, radical, and molecular. More detailed classifications have also been made. The mechanisms of many reactions involving non-transition metal compounds are clear enough for example, in the Grig-nard or Reformatsky reaction, the first step is the irreversible oxidative addition of alkyl halides to form Mg-carbon or Zn-carbon bonds, in which the carbon is considered to be a nucleophilic center or carbanion which reacts with various electrophiles. 

Notice that the number of alkyl groups attached to the nitrogen determines whether an amine is primary, secondary, or tertiary. For an alkyl halide or an alcohol, on the other hand, the number of alkyl groups attached to the carbon to which the halogen or the OH is bonded determines the classification (Sections 2.4 and 2.6). 

Alkyl halides are classified as being primary (1°), secondary (2°), or tertiary (3°). This classification is based on the carbon atom to which the halogen is directly attached. If the carbon atom that bears the halogen is directly attached to only one other carbon, the carbon atom is said to be a primary carbon atom and the alkyl halide is classified as a primary alkyl halide. If the carbon that bears the halogen is itself directly attached to two other carbon atoms, then the carbon is a secondary carbon and the alkyl halide is a secondary alkyl halide. If the carbon that bears the halogen is directly attached to three other carbon atoms, then the carbon is a tertiary... 

Chemical Tests. You may wish to perform several classification tests on the product (see Chapter 9). Carry out the ignition test to confirm the presence of an aromatic group. The Beilsfein tesf can be used to detect the presence of bromine. The silver nitrafe fesf for alkyl halides should also give a positive result. 

Claisen head adapter, 20, 26,134 Claisen-Schmidt reaction, 309-317 classification tests, 640-654. See also qualitative analysis alcohols, 640-642 aldehydes, 642-644 alkanes, 644-645 alkenes, 645 alkyl halides, 645-646 aUcynes, 645 amides, 647-648 amines, 648-649 ammonium salts, 647-648 aromatic hydrocarbons, 649-650 carboxylic acids, 650 cycloalkanes, 644-645 defined, 630 enols, 653-654 esters, 650-651 ethers, 651... 

Classification of alkyl halides as primary, secondary, or tertiary. 

It must be emphasized that the duodectet rule (4.6) initially has no structural connotation, but is based on composition only. Indeed, the compositional regularity expressed by (4.6) encompasses both molecular species (such as the metal alkyls) and extended lattices (such as the oxides and halides) and therefore appears to transcend important structural classifications. Nevertheless, we expect (following Lewis) that such a rule of 12 may be associated with specific electronic configurations, bond connectivities, and geometrical propensities (perhaps quite different from those of octet-rule-conforming main-group atoms) that provide a useful qualitative model of the chemical and structural properties of transition metals. 

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