The maximum number ofpossible isomers of A is 36, considering the fact that the three monomers i-iii readily isomerise at 20" via 1,s-H-shifts (equilibration ratio -1:45:54 [5]), and that each monomer may undergo Diels-Alder-type self-and cross-dimerisation.
Solution behaviour and redistribution reactions of tetraorganodistannoxane dimers
β Scribed by Vimal K. Jain; V. B. Mokal; P. Sandor
- Publisher
- John Wiley and Sons
- Year
- 1992
- Tongue
- English
- Weight
- 437 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0749-1581
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β¦ Synopsis
Abstract
The solution behaviour and redistribution reactions of tetraorganodistannoxane dimers were investigated by ^19^F and ^119^Sn NMR spectroscopy. The variableβtemperature NMR data suggest that both the βladderβ and βstaircaseβ structures exist in solution. Redistribution between two different tetrabutylstannoxanes is rapid on the NMR time scale. The ^119^Sn 2D EXSY NMR data for [Bu~2~Sn(F)OSnBu~2~(Cl)]~2~ indicate that there is no exchange between exoβ and endocyclic tin centres.
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