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Substituent Effect on Aniline Carbonylation Reaction in the Presence of the PdCl2/Fe/I2/Py Catalytic System

100%

Karpińska M. , Baran P. , Skupińska J.

2008

tom Vol. 82, nr 5

1105-1116

A study of the effect of substituents in the aromatic ring on the aniline carbonylation reaction in the presence of the PdCl2/Fe/I2/Py catalytic system, where oxygen or nitrobenzene were used as oxidants, showed that the electronodonor substituents accelerate the aniline carbonylation reaction, when the reaction is conducted in the presence of oxygen. For nitrobenzene used as an oxidant in this reaction substituent was found to have no ef fect on the carbamate yield. The nitrobenzene reduction is the rate-determining step in the aniline carbonylation process.

Recent Developments in Palladium-Catalyzed Carbonylation of Steroids - An Alternative Approach to Steroidal Carbonyl Compounds and Carboxylic Acid Derivatives

88%

Skoda-Foldes R. , Kollar L.

2006

tom Vol. 80, nr 4

587-604

There is an increasing interest in developing new strategies to introduce functional groups into specific positions of steroidal nuclei in order to modify their biological properties. Transition metal catalyzed reactions have proved to be versatile tools both for the construction of the steroid framework from easily available building blocks and for the functionalization of the steroidal skeleton. By palladium-catalyzed carbonylation, carbon monoxide can be introduced directly into a number of different sites in an organic molecule leading to the synthesis of aldehydes, ketones, carboxylic acids and their derivatives, lactones, lactames, etc. The products can often be obtained in good yield and with high selectivity usually under very mild conditions. In addition, palladium-catalyzed carbonylation is compatible with many functional groups, and therefore, more advantageous than conventional methods. In the present paper the most important achievements in carbonylation of steroidal substrates is reviewed together with a more detailed discussion of our own results obtained in this field.

Otrzymywanie poliwęglanów na drodze utleniającego karbonylowania hydroksyzwiązków

75%

Kuczyńska L. , Skupińska J. , Wielgosz Z.

2001

tom Vol. 50, nr 23

221-224

Otrzymano poliwęglan w reakcji utleniającego karbonylowania bisfenolu A mieszaniną tlenku węgla i tlenu w obecności katalizatorów. Aktywnymi katalizatorami tej reakcji okazały się selen, chlorek rodu oraz układy zawierające pallad i jego związki z dodatkiem związków miedzi i żelaza jako kokatalizatorów redoks. Otrzymany poliwęglan ma łańcuch zakończony grupą OH lub o-węglanemfenylenu.

Bisphenol oxidising carbonylation with carbon monoxide and oxygen to polycarbonates in the presence of catalysts containing selenium, rhodium palladium and iron, cooper derivatives as co-catalysts, has been studied. The palladium-cooper catalytic system exhibited the highest activity.