The pinanes are preferably attacked at the tertiary C‐H bond in 2‐position, but products of the oxidative attack at the secondary C‐H bonds in 3‐ and 4‐position are also found. At 100°C cis‐pinane is attacked more easily than trans‐pinane (kcis : ktrans = 6.4), the relative rates of attack at the secondary C‐H bonds in positions 3 and 4 with respect to the tertiary C‐H bond in 2‐position were also determined (in cis‐pinane ksec: ktert = 0.027; in trans‐pinane ksec : ktert = 0.20). After the attack at the 2‐C‐H bond the radical formed can either react with oxygen to form the corresponding cis‐ and trans‐peroxy radicals and further to give cis‐ and trans‐2‐hydroperoxy pinane or fragmentate to the monocyclic radical derived from α‐terpinene, giving as final products α‐terpinene hydroperoxide and the bicyclic 8‐hydroperoxy 4,4,8‐trimethyl 2,3‐dioxabicyclo[3.3.1]nonane. The corresponding alcohols were found after reduction with sodium sulphite. The oxidation at position 2 of the pinanes delivers not only the cis‐ and trans‐hydroperoxide but also, as shortlived intermediates, the corresponding 2‐pinanyloxy radicals. These radicals fragmentate forming a carbon radical with cyclobutane structure whose oxidation products were identified. Besides fragmentation of the 2‐pinanyloxy radical also an intramolecular H‐transfer from the methyl group in 9‐position to the oxygen of the trans‐2‐pinanyloxy radical takes place leading to 9‐hydroperoxy trans‐pinane‐2‐ol.
Nitrobenzene, α‐nitronaphthalene, m‐dinitrobenzene, 1,3,5‐trinitrobenzene, m‐nitrobenzophenone, m‐nitrobenzonitrile, methyl m‐nitrobenzoate and m‐nitro diphenylsulphone can be hydroxylated with cumene or tert‐butyl hydroperoxide in dipolar aprotic solvents in the presence of strong bases. The hydroxyl group is introduced preferably in p‐position to the nitro group. Attempts to hydroxylate benzophenone, anthraquinone, 2‐ethyl anthraquinone, anthraquinone 2‐sulphonate, benzonitrile and diphenyl sulphone under the same conditions failed. 1‐Nitroanthraquinone delivered 1‐hydroxy, 1,2‐dihydroxy and 1,4‐dihydroxy anthraquinone.
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