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Denne oppgaven er en teoretisk drøfting av hvem det stille barnet er, og hvordan stille atferd kan påvirke barn sosialt og faglig. Ved å drøfte ulike begreper og definisjoner knyttet til stille atferd har jeg funnet at stille barn kan defineres på ulike måter. Funnene tyder likevel på at noen kjennetegn går igjen, og viser at det er en del fellestrekk mellom de ulike begrepene og definisjonene. Hvem som omtaler den stille atferden, og hvilke forklaringsmodeller de legger til grunn, har også vist seg å være avgjørende for hvilke begreper og definisjoner som benyttes for å omtale stille atferd. Mot slutten av oppgaven rettes oppmerksomheten mot mulige sosiale og faglige konsekvenser, knyttet til stille atferd, og jeg viser at atferden kan få ulike konsekvenser. Noen konsekvenser er knyttet til psykiske forhold, mens andre konsekvenser kan vise seg i samhandling med andre, eller som vansker knyttet til å prestere opp mot forventninger.

Nürtingen, FH, Diplomarb., 2004. / Betreuer: Helmut Rieker.

Zugl.: Münster (Westfalen), Univ., Diss., 2008

A reação de acoplamento Stille catalisada por paládio representa um das transformações mais importantes na construção de ligação carbono-carbono. Embora os diarilmetanos sejam estruturas importantes em vários compostos orgânicos, as reações de Stille, particularmente catalisadas por paládio, utilizando haletos de benzila têm sido bem menos estudadas que as reações de acoplamento com haletos de arila. Neste trabalho, foram desenvolvidos dois sistemas para a formação de diarilmetanos via reação de acoplamento Stille catalisado por paládio entre derivados de cloretos de benzila e derivados de feniltributilestanho. O primeiro sistema otimizado é composto por 4 mol % de Pd(OAc)2, 8 mol % de dppf (dppf = 1,1'- bis(difenilfosfino)ferroceno), 1 mmol de KF, 80oC, 3h e 1,4-dioxano como solvente; e o segundo sistema utiliza 2-4 mol % de Pd(OAc)2, 4-8 mol % de PPh3, sem adição de base ou aditivo, 80oC, 20h e 1,4-dioxano como solvente. Os correspondentes derivados de diarilmetanos foram obtidos com bons a excelentes rendimentos (66-100%). / The palladium-catalyzed Stille cross-coupling reaction represents one of the most important transformations in constructing the carbon-carbon bonds. Although diarylmethanes are important building blocks in organic synthesis, the Stille crosscoupling reaction, Pd-catalyzed particularly, using benzylic halides have been less exploited than the corresponding reaction with aryl halides. In this work, two systems were developed for the formation of diarylmethanes through Stille cross-coupling reaction Pd-catalyzed between benzylic chlorides derivatives and phenyltributyltin derivatives. The first optimized system is composed by 4 mol % of Pd(OAc)2, 8 mol % of dppf (dppf = 1,1'-bis(diphenylphophino)ferrocene), 1 mmol of KF, 80oC, 3h and 1,4-dioxano as solvent; and the second system uses 2-4 mol % of Pd(OAc)2, 4-8 mol % of PPh3, without addition of base or addictive, 80oC, 20h and 1,4-dioxano as solvent. The diarylmethanes derivatives correspondents were obtained with good to excellent yields (66-100%).

A reação de acoplamento Stille catalisada por paládio representa um das transformações mais importantes na construção de ligação carbono-carbono. Embora os diarilmetanos sejam estruturas importantes em vários compostos orgânicos, as reações de Stille, particularmente catalisadas por paládio, utilizando haletos de benzila têm sido bem menos estudadas que as reações de acoplamento com haletos de arila. Neste trabalho, foram desenvolvidos dois sistemas para a formação de diarilmetanos via reação de acoplamento Stille catalisado por paládio entre derivados de cloretos de benzila e derivados de feniltributilestanho. O primeiro sistema otimizado é composto por 4 mol % de Pd(OAc)2, 8 mol % de dppf (dppf = 1,1'- bis(difenilfosfino)ferroceno), 1 mmol de KF, 80oC, 3h e 1,4-dioxano como solvente; e o segundo sistema utiliza 2-4 mol % de Pd(OAc)2, 4-8 mol % de PPh3, sem adição de base ou aditivo, 80oC, 20h e 1,4-dioxano como solvente. Os correspondentes derivados de diarilmetanos foram obtidos com bons a excelentes rendimentos (66-100%). / The palladium-catalyzed Stille cross-coupling reaction represents one of the most important transformations in constructing the carbon-carbon bonds. Although diarylmethanes are important building blocks in organic synthesis, the Stille crosscoupling reaction, Pd-catalyzed particularly, using benzylic halides have been less exploited than the corresponding reaction with aryl halides. In this work, two systems were developed for the formation of diarylmethanes through Stille cross-coupling reaction Pd-catalyzed between benzylic chlorides derivatives and phenyltributyltin derivatives. The first optimized system is composed by 4 mol % of Pd(OAc)2, 8 mol % of dppf (dppf = 1,1'-bis(diphenylphophino)ferrocene), 1 mmol of KF, 80oC, 3h and 1,4-dioxano as solvent; and the second system uses 2-4 mol % of Pd(OAc)2, 4-8 mol % of PPh3, without addition of base or addictive, 80oC, 20h and 1,4-dioxano as solvent. The diarylmethanes derivatives correspondents were obtained with good to excellent yields (66-100%).

A reação de acoplamento Stille catalisada por paládio representa um das transformações mais importantes na construção de ligação carbono-carbono. Embora os diarilmetanos sejam estruturas importantes em vários compostos orgânicos, as reações de Stille, particularmente catalisadas por paládio, utilizando haletos de benzila têm sido bem menos estudadas que as reações de acoplamento com haletos de arila. Neste trabalho, foram desenvolvidos dois sistemas para a formação de diarilmetanos via reação de acoplamento Stille catalisado por paládio entre derivados de cloretos de benzila e derivados de feniltributilestanho. O primeiro sistema otimizado é composto por 4 mol % de Pd(OAc)2, 8 mol % de dppf (dppf = 1,1'- bis(difenilfosfino)ferroceno), 1 mmol de KF, 80oC, 3h e 1,4-dioxano como solvente; e o segundo sistema utiliza 2-4 mol % de Pd(OAc)2, 4-8 mol % de PPh3, sem adição de base ou aditivo, 80oC, 20h e 1,4-dioxano como solvente. Os correspondentes derivados de diarilmetanos foram obtidos com bons a excelentes rendimentos (66-100%). / The palladium-catalyzed Stille cross-coupling reaction represents one of the most important transformations in constructing the carbon-carbon bonds. Although diarylmethanes are important building blocks in organic synthesis, the Stille crosscoupling reaction, Pd-catalyzed particularly, using benzylic halides have been less exploited than the corresponding reaction with aryl halides. In this work, two systems were developed for the formation of diarylmethanes through Stille cross-coupling reaction Pd-catalyzed between benzylic chlorides derivatives and phenyltributyltin derivatives. The first optimized system is composed by 4 mol % of Pd(OAc)2, 8 mol % of dppf (dppf = 1,1'-bis(diphenylphophino)ferrocene), 1 mmol of KF, 80oC, 3h and 1,4-dioxano as solvent; and the second system uses 2-4 mol % of Pd(OAc)2, 4-8 mol % of PPh3, without addition of base or addictive, 80oC, 20h and 1,4-dioxano as solvent. The diarylmethanes derivatives correspondents were obtained with good to excellent yields (66-100%).

The Stille reaction has established itself as one of the two most general and most selective palladium-catalyzed cross-coupling reactions, along with the Suzuki cross-coupling of organoboron compounds. The Stille coupling of α-alkoxystannanes is a relatively unexplored area. A previous study showed that an α-alkoxyalkylstannane could be coupled with benzoyl chloride with retention of configuration. However, our group has recently shown that Stille couplings of sulfonamidobenzylstannanes proceeds with inversion of configuration. In order to determine whether the Stille coupling reaction of α-alkoxybenzylstannanes proceeds with inversion or retention, the stereochemistry in the Stille reaction of α-alkoxybenzylstannanes was studied. Optimized conditions for Stille coupling of α-alkoxybenzyl-tributylstannanes with benzoyl chloride were developed: highest yields were observed using Pd2dba3 and PPh3 in toluene. Enantiomerically enriched α-hydroxystannanes were obtained via chromatographic resolution of diastereomeric carbamate derivatives. An X-ray crystal structure was obtained for the 3,5-dinitrobenzoate derivative of (S)-1-hydroxyphenylmethyl-trimethylstannane. Stille coupling (cat. Pd2dba3, PPh3, toluene) of the corresponding acetate with benzoyl chloride provided the acetate of (R)-benzoin thus establishing retention of configuration under these reaction conditions.

The Stille reaction has established itself as one of the two most general and most selective palladium-catalyzed cross-coupling reactions, along with the Suzuki cross-coupling of organoboron compounds. The Stille coupling of α-alkoxystannanes is a relatively unexplored area. A previous study showed that an α-alkoxyalkylstannane could be coupled with benzoyl chloride with retention of configuration. However, our group has recently shown that Stille couplings of sulfonamidobenzylstannanes proceeds with inversion of configuration. In order to determine whether the Stille coupling reaction of α-alkoxybenzylstannanes proceeds with inversion or retention, the stereochemistry in the Stille reaction of α-alkoxybenzylstannanes was studied. Optimized conditions for Stille coupling of α-alkoxybenzyl-tributylstannanes with benzoyl chloride were developed: highest yields were observed using Pd2dba3 and PPh3 in toluene. Enantiomerically enriched α-hydroxystannanes were obtained via chromatographic resolution of diastereomeric carbamate derivatives. An X-ray crystal structure was obtained for the 3,5-dinitrobenzoate derivative of (S)-1-hydroxyphenylmethyl-trimethylstannane. Stille coupling (cat. Pd2dba3, PPh3, toluene) of the corresponding acetate with benzoyl chloride provided the acetate of (R)-benzoin thus establishing retention of configuration under these reaction conditions.

Zugl.: Erlangen, Nürnberg, Universiẗat, Diss., 2009.