Structure Reactivity-Relationships in the Chemistry of Aliphatic Free Radicals

The effect of alkyl substitution on the oxidative cleavage of alkylphenylmethanols by ceric ammonium nitrate

“…This conformational effect does not influence the formation of carbanions (42,43). In fact, the rates of formation of carbonium ions and carbanions depend character istically and differently on ring size (42,43).…”

“…The decomposition of azo-l-methylcyclopentane is ça. 10 times faster than the azo-l-methylcyclohexane (42). The rate of horaolytic fragmentation of cycloalkyl peroxy esters de creases roughly as the size of the ring decreases (42,43).…”

“…His postulation requires that all ç> values be negative and he has predicted that ç«-1 Polar effects are thought to be important factors in many free radical forming reactions. Euchardt and coworkers have reviewed the relations between structure and reactivity in free radical chemistry (42,43). They, pointed out that polar effects have a strong influence on the rate of fragmentation of peroxy esters.…”

“…For example, changing a tetravalent carbon to a trivalent carbon relieves strain for a fivemembered ring while the strain is increased for a six-membered ring (47,48). Solvolysis of 1-methylcyclopentyl chloride is 100 times faster than for 1-methylcyclohexyl chloride (42,43,47). This conformational effect does not influence the formation of carbanions (42,43).…”

“…Solvolysis of 1-methylcyclopentyl chloride is 100 times faster than for 1-methylcyclohexyl chloride (42,43,47). This conformational effect does not influence the formation of carbanions (42,43). In fact, the rates of formation of carbonium ions and carbanions depend character istically and differently on ring size (42,43).…”