Hydrocarbons, hydrocarbon methyl groups

Shorthand notation for pheromone molecules for example, (Z)-7-dodecen-l-yl acetate is shortened to Z7-12 OAc where the Z denotes the double bond configuration (Z or E), 7 the double bond position, 12 the number of carbons in the chain, OAc indicates the functional group as an acetate ester. Aid = aldehyde, Co A = coenzyme A, D = deuterium, Epox = epoxide, He = hydrocarbon, me = methyl group, OH = alcohol. 

In the given hydrocarbon a methyl group is represented by R, an ethyl group by R and a propyl by R. What is the name of the following compound ... 

Either individually or in combination, these are excellent catalysts for oxidation of aromatic hydrocarbons (methyl groups) to aldehydes and acids. 

The formula CH3-H contains the CH3 group, which is called methyl. It plays an important part in the composition of the hydrocarbons. The methyl group has only one valency and replaces any one hydrogen atom of a pre-existing hydrocarbon. The first five hydrocarbons of this series are shown in Table 2-4. 

Consider aliphatic hydrocarbons. A methyl group (CH3) at the end of a long aliphatic chain will show a resonance with a shift of about 0.75 ppm. Figure 4.1 shows the shifts for the resonances of the aliphatic side chain of 5-hydroxydodecanoic acid 5-lactone. The methyl H s (position 12) that are nine bonds removed from the oxygen atom of the carbonyl group are sufficiently well isolated to... 

CH3 group. Fox and Martin [6] examined a large number of hydrocarbons containing methyl groups, and found that in all cases... 

Aromatic hydrocarbons with aliphatic side chains, e.g., toluene, do not form mercapturic acids at all. Instead, the side chain is oxidized to a carboxyl group. Similarly, alcohols, aldehydes, phenols, etc., are not converted to mercapturic acids. On polycyclic hydrocarbons, a methyl group may be slowly attacked. 7-Methyh and 12-methylbenz(a)anthra cene form traces of mercapturic acids but 7,l2-diraethylbenz a)anthracene forms none. 

We can relate the conformational preference for an equatorial methyl group m methylcyclohexane to the conformation of a noncyclic hydrocarbon we discussed ear her butane The red bonds m the following structural formulas trace paths through four carbons beginning at an equatorial methyl group The zigzag arrangement described by each path mimics the anti conformation of butane... 

Hydrocarbon Positions of methyl group Number of pairs ia 1,3-positions Basicity... 

Nitriles. Nitriles can be prepared by a number of methods, including ( /) the reaction of alkyl haHdes with alkaH metal cyanides, (2) addition of hydrogen cyanide to a carbon—carbon, carbon—oxygen, or carbon—nitrogen multiple bond, (2) reaction of hydrogen cyanide with a carboxyHc acid over a dehydration catalyst, and (4) ammoxidation of hydrocarbons containing an activated methyl group. For reviews on the preparation of nitriles see references 14 and 15. 

---