A quartz multiatomizer with its inlet arm modified to serve as a trap (trap and atomizer device) was employed to trap the tin hydride and subsequently to volatilize collected analyte species with atomic absorption spectrometric detection. Generation, atomization and preconcetration conditions were optimized and analytical figures of merit of both on-line atomization as well as preconcentration modes were quantified. Preconcentration efficiency of 95 ± 5 % was found. The detection limits reached were 29 and 143 pg ml-1 Sn, respectively, for 120 second preconcentration period and on-line atomization mode without any preconcentration. The interference extent of other hydride forming elements (As, Se, Sb and Bi) on tin determination was found negligible in both modes of operation. The applicability of the developed preconcentration method was verified by Sn determination in a certified reference material as well as by analysis of real samples. Key words HG-AAS, multiatomizer (multiple microflame quartz tube atomizer), trap and atomizer device, tin determination, stannane, in atomizer trapping, interference study

Investigation of the catalytic formation, reactivity and synthetic scope of sp³-gem-organodimetallic palladio(II)/main group metal (main group metal = tributylstannyl, dialkylalumino) alkane species has been carried out. Insight was expanded regarding the inter- and intramolecular reactivity of vinylmetallic reagents in presence of transition metal catalysts. New Pd-catalysed methodologies for carbon-carbon bond formation were developed, such as cyclopropanation of strained olefins, as well as tandem vinylalane arylation/1,2-methyl transfer and 1,2-diarylation. On the one hand, geminal π-allylpalladio(II)/tributylstannylalkane intermediates are produced by oxidative addition of Pd(0) catalysts to α-tributylstannylpropenyl acetate derivatives. They adopt ambiphilic behaviour depending on the transition metal pre-catalyst, presence or absence of phosphine ligands, and reaction temperature. In presence of tetrakis(triphenylphosphine)palladium(0) with additional bidentate ligand, the carbenoid reactivity of these gem-organobismetallic species is exposed by reaction with dimethyl malonate. Deuterium-labeling studies demonstrated sequential functionalisation of the C-Sn and C-Pd bonds. Conversely, phosphine-free catalyst bis(dibenzylideneacetone)palladium(0) uncovers metal-carbene reactivity, and dimerisation and strained alkene cyclopropanation reactions are observed. The nature of the palladium catalyst controls the reactivity of the carbenoid species. Finally, bis(cyclooctadienerhodium(I) chloride) catalytically activates the alkenylstannane moiety, leaving the allylic acetate leaving group available for further transformations. On the other hand, gem-disubstituted trifluoromethanesulfonyloxy- and iodopalladio(II)/ dialkylaluminoneopentane species are generated by intramolecular migratory insertion of 2,2-disubstituted-1-butenyldialkylalanes with σ-arylpalladium(II) triflate and iodide intermediates. Using excess Lewis-basic 1,4-diazabicyclo[2.2.2]octane, electron-rich tris(para-methoxyphenyl)phosphine ligand and acetonitrile as solvent, tandem arylation/1,2-alkyl migration from aluminum to carbon affords 7-substituted-1-ethyl-1-methylindanes containing an all-carbon quaternary stereogenic centre in good yields. This reaction is tolerant of 6-aryl methyl ethers, thioethers and trimethylsilanes. Deuterium labeling established that protiodealumination of the key neopentyl(methyl)aluminum triflate intermediate is caused by the acetonitrile solvent. The organodimetallic species in that study were shown to be configurationally stable, hence the stereospecificity of the process that proceeds via carbopalladation, transmetalation and reductive elimination of an alkylpalladium(II) intermediate. When applied to 1-naphthyl triflate-tethered vinylalanes, the same reaction conditions mediate stereospecific 1,2-diarylation, leading to 2,3,3a,4-tetrahydro-1H-cyclopenta[def]phenanthrenes in excellent yields. The influence of DABCO, tether length and solvent polarity was studied. Selective tandem arylation/1,2-methyl migration could also be achieved in non-polar solvent in absence of Lewis base. While steric properties took precedence over electronic considerations when inducing product selection, preagostic C-H···Pd interactions were postulated to facilitate 1,3-metal migration in the production of 1H-cyclopenta[def]phenanthrene derivatives.

Investigation of the catalytic formation, reactivity and synthetic scope of sp³-gem-organodimetallic palladio(II)/main group metal (main group metal = tributylstannyl, dialkylalumino) alkane species has been carried out. Insight was expanded regarding the inter- and intramolecular reactivity of vinylmetallic reagents in presence of transition metal catalysts. New Pd-catalysed methodologies for carbon-carbon bond formation were developed, such as cyclopropanation of strained olefins, as well as tandem vinylalane arylation/1,2-methyl transfer and 1,2-diarylation. On the one hand, geminal π-allylpalladio(II)/tributylstannylalkane intermediates are produced by oxidative addition of Pd(0) catalysts to α-tributylstannylpropenyl acetate derivatives. They adopt ambiphilic behaviour depending on the transition metal pre-catalyst, presence or absence of phosphine ligands, and reaction temperature. In presence of tetrakis(triphenylphosphine)palladium(0) with additional bidentate ligand, the carbenoid reactivity of these gem-organobismetallic species is exposed by reaction with dimethyl malonate. Deuterium-labeling studies demonstrated sequential functionalisation of the C-Sn and C-Pd bonds. Conversely, phosphine-free catalyst bis(dibenzylideneacetone)palladium(0) uncovers metal-carbene reactivity, and dimerisation and strained alkene cyclopropanation reactions are observed. The nature of the palladium catalyst controls the reactivity of the carbenoid species. Finally, bis(cyclooctadienerhodium(I) chloride) catalytically activates the alkenylstannane moiety, leaving the allylic acetate leaving group available for further transformations. On the other hand, gem-disubstituted trifluoromethanesulfonyloxy- and iodopalladio(II)/ dialkylaluminoneopentane species are generated by intramolecular migratory insertion of 2,2-disubstituted-1-butenyldialkylalanes with σ-arylpalladium(II) triflate and iodide intermediates. Using excess Lewis-basic 1,4-diazabicyclo[2.2.2]octane, electron-rich tris(para-methoxyphenyl)phosphine ligand and acetonitrile as solvent, tandem arylation/1,2-alkyl migration from aluminum to carbon affords 7-substituted-1-ethyl-1-methylindanes containing an all-carbon quaternary stereogenic centre in good yields. This reaction is tolerant of 6-aryl methyl ethers, thioethers and trimethylsilanes. Deuterium labeling established that protiodealumination of the key neopentyl(methyl)aluminum triflate intermediate is caused by the acetonitrile solvent. The organodimetallic species in that study were shown to be configurationally stable, hence the stereospecificity of the process that proceeds via carbopalladation, transmetalation and reductive elimination of an alkylpalladium(II) intermediate. When applied to 1-naphthyl triflate-tethered vinylalanes, the same reaction conditions mediate stereospecific 1,2-diarylation, leading to 2,3,3a,4-tetrahydro-1H-cyclopenta[def]phenanthrenes in excellent yields. The influence of DABCO, tether length and solvent polarity was studied. Selective tandem arylation/1,2-methyl migration could also be achieved in non-polar solvent in absence of Lewis base. While steric properties took precedence over electronic considerations when inducing product selection, preagostic C-H···Pd interactions were postulated to facilitate 1,3-metal migration in the production of 1H-cyclopenta[def]phenanthrene derivatives.