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The formal transformation of cyclopentadiene to cis-bicyclo[3.3.0]octanes via endo-5-vinyl-2-norbornene involving two different oxidation reactions, such as Pd-catalysed cyclisation and Baeyer–Villiger (BV) ring opening is described.

The synthesis and characterization of a new active P*-active phosphapalladacycle and its successful use in the asymmetric hydroarylation of norbornene with turnover numbers (TONs) of up to 1010 is described.

The synthesis and characterization of a new active P*-active phosphapalladacycle and its successful use in the asymmetric hydroarylation of norbornene with turnover numbers (TONs) of up to 1010 is described.

La cyclisation oxydante de dienes-1,5 dans l'acide acetique en presence d'un systeme catalytique se regenerant a base de Pd(II)/Pd(OAc) 2 /MnO 2 /p-benzoquinone conduit, en fonction de la structure du diene-1,5, a des acetoxyexomethylenecyclopentanes ou a des acetoxyvinylcyclopentanes. Cette methode permet d'acceder a des nouveaux systemes cyclopentaniques

In methylene vinylethers 3–5 NOE effects allow the establishment of the proximity of four hydrogen atoms in line thus confirming more rigorously the absolute configuration of secondary alcohols previously determined in O-aryl lactic esters.

The 1H NMR analysis of O-aryllactic esters allows the attribution of the absolute configuration to alcohols according to a new model with Hα in the acid plane in a hitherto unprecedented conformation.

Molecular sieves have a decisive influence on the oxidative cyclisation of cis-1,2-divinylcyclohexane, resulting in enhanced diastereoselectivity (17–62%) as well as, occasionally, in opposite absolute configuration of the newly created chiral centres.

The reactivity of di-p-chlorobis[3-(nitrosooxy)bicyclo[2.2.]] hept-2-yl-C,N]dipalladium II can be modified by added reagents. In presence of CuCl2, the thermal decomposition leading to epoxynorbornane is completely suppressed and an unequivocal rearrangement of the norbornane framework is observed.

La cyclisation oxydante de dienes-1,5 dans l'acide acetique en presence d'un systeme catalytique se regenerant a base de Pd(II)/Pd(OAc) 2 /MnO 2 /p-benzoquinone conduit, en fonction de la structure du diene-1,5, a des acetoxyexomethylenecyclopentanes ou a des acetoxyvinylcyclopentanes. Cette methode permet d'acceder a des nouveaux systemes cyclopentaniques

Oxydation de derives du norbornene et de quelques hydrocarbures dieniques aliphatiques ou non: on observe une epoxydation selective pour les derives du norbornene et on obtient des cetones pour les autres

In order to investigate the possibility of improving the selectivity in palladium-catalyzed acetoxylation of substituted cycloalkenes and linear alkenes, the influence of added strong acids has been studied. It was found that the product selectivity can be increased in some cases, but also that side reactions lower the total yields when trifluoroacetic or stronger acids are used. The improvement of the selectivity may possibly be due to a change in mechanism for the acetoxylation.

Das vollstandige Manuskript dieser Zuschrift erscheint in: Angew. Chem. Suppl. 1982, 922. DOI: 10.1002/ange.198209220

1,5-Bismethylene cyclooctane 1 is transformed in a one pot multi step sequence to bridgehead substituted bicyclo [ 4. 3. 1 ] decane derivatives by a catalytical Pd II mediated oxidation reaction. A regioselective Wagner Meerwein rearrangement leading to ring enlargement is involved. The major product 5 can be fragmentated to a nine membered ring .

Thermal cyclization of cyclooctene-4-yl-carboxylic acid chloride ( 5 ) and cycloheptene-4-yl-carboxylic acid chloride ( 10 ) yielded mixtures of mainly endo and exo 2-chlorobicyclo[3.3.1]nonane-9-one ( 7 and 8 ), and mixtures of endo and exo 2-chlorobicyclo[3.2.1]octane-8-one ( 12 and 13 ), respectively. AlCl 3 -catalyzed cyclization of 10 gave the same product composition as the uncatalyzed reaction. In the AlCl 3 -catalyzed cyclization of 5 considerable amounts of bicyclo[3.3.1]non-2-en-9-one ( 6 ) and exo 3-chlorobicyclo[3.3.1]nonane-9-one ( 9 ) were obtained in addition to 7 and 8 .

Hexa-1,5-dienes undergo oxidative ring closure catalysed by palladium acetate using p-benzoquinone–manganese dioxide as oxidant to give acetoxy-substituted methylene-cyclopentane derivatives.

Etude des reactions des chlorures de neopentyl- et cyclohexylmethyl- mercure, catalysees par l'acetate de palladium (II) en presence de CuCl 2 -LiCl-acide acetique

La conversion selective de monoolefines en acetates d'allyle est realisee avec un nouveau systeme catalytique. On transforme ainsi le cyclohexene en acetoxy-3cyclohexene en presence de Pd(OAc) 2 /benzoquinone/MnO 2 -HOAc avec un rendement de 60-90%

Hexa-1,5-dienes undergo oxidative ring closure catalysed by palladium acetate using p-benzoquinone–manganese dioxide as oxidant to give acetoxy-substituted methylene-cyclopentane derivatives.

Aus dem N-Chlor-amin (I) erhalt man mit Aluminiumchlorid oder mit Bortri= fluoridatherat die Umlagerungsprodukte (IIa), (IIIa) und (IV), mit Aluminiumbromid neben (IV) die entsprechenden Bromide (IIb) und (IIIb).

Several mono or non conjugated diolefins are submitted to the action of oxygen in presence of catalytic amounts of PdCl (NO2) (CH3CN)2. Depending on the olefin structures methylketones or epoxides are obtained.

On donne l'exemple de la reaction du trans-deuterio-1 decene-1 avec Pd(Cl)(NO 2 )(CH 3 CN) 2 dans l'acide acetique en atmosphere d'air

La conversion selective de monoolefines en acetates d'allyle est realisee avec un nouveau systeme catalytique. On transforme ainsi le cyclohexene en acetoxy-3cyclohexene en presence de Pd(OAc) 2 /benzoquinone/MnO 2 -HOAc avec un rendement de 60-90%