Novel cobalt(II1) alkylperoxy complexes with the general formula Co(R"BPI)(OCOR')(OOR) [type I, R" = H, Me; BPI = 1,3-bis(2'-pyridylimino)isoindoline, R' = Me, Ph, t-Bu; R = t-Bu, CMe2Ph] and Co(BPB)(OOt-Bu)(4-Mepy) [type 11, BPB = N,N'-bis(2'-pyridinecarboxamide)-1,2-benzene] were synthesized from the reaction of alkyl hydroperoxides with their Co(I1) precursor, and characterized by physicochemical methods. The X-ray structure of Ib (R" = H, R' = Ph, R = t-Bu) revealed a distorted octahedral environment with a chelating carboxylate moiety and an apically bonded tert-butylperoxy group. The reactivity of cobalt(II1) alkylperoxy complexes toward hydrocarbons was found to be dependent on their thermal decomposition rate, with type I complexes being the most reactive ones. Saturated hydrocarbons are oxidized by Co(II1) tert-butylperoxy complexes into alcohols, ketones, and tert-butylperoxy products. The hydroxylation reaction preferentially occurs at the more nucleophilic C-H bonds with extensive epimerization at the hydroxylated carbon atom. Hydrocarbons having labile allylic or benzylic C-H bonds react beginning at room temperature to give a large amount of allylic or benzylic tert-butyl peroxide. Olefins having no allylic hydrogen atom are preferentially transformed into epoxides. The catalytic hydroxylation of alkanes by t-BuOOH in the presence of complexes 1-111 has the same characteristics as the stoichiometric reaction. The homolytic decomposition and reactivity of cobalt(II1) alkylperoxy complexes is discussed in the context of the Haber-Weiss mechanism of alkyl hydroperoxide decomposition and of hydrocarbon hydroxylation by first-row transition-metal peroxides.

Prototypes of new families of precatalysts and catalysts, [Ru((−)‐Me‐DuPHOS)(H)(η6‐1,3,5‐cyclooctatriene)](BF4) and the derived “[Ru((−)‐Me‐DuPHOS)(H)(sol)](BF4)”, are presented. They are used in an industrial, catalytic, enantioselective hydrogenation that leads to (+)‐cis‐methyl dihydrojasmonate [Eq. (1)]. This stereoisomer is the odorant component of an important, large volume perfumery chemical. P−P=Diphosphane ligand (for example, Me‐DuPHOS=1,2‐bis((2R,5R)‐2,5‐dimethylphospholanyl)benzene); sol=solvent.

Die Jasmonoide, ()-cis-Jasmonsäure und ihre Derivate, haben zahlreiche phytobiologische Aktivitäten, [1] und der Methylester ()-cis-Methyljasmonat [2] ()-1 weist unter anderem auch einen Geruch auf, [3] der in der Parfümerie hoch geschätzt wird. [4] Das Studium der Jasmonoide begann 1962, als eine weitgehend äquilibrierte Mischung von (À)-trans-Methyljasmonat (À)-2 (Hauptkomponente, siehe unten) und CO 2 Me O CO 2 Me O CO 2 Me O CO 2 Me O CO 2 Me O (+)-1 (-)-2 (+)-3 (-)-4 5 [*] Dr.

No abstract

Die Co(III)‐alkylperoxy‐Komplexe (II), (IV) und (VI) werden wie aufgezeichnet dargestellt und durch physikochemische Methoden charakterisiert.