Maclafferty Rearrangement in Germyl Derivatives of Organo-tin Carboxylates

Abstract

Bimetallic compounds of general formula [(R¹)₃GeCHR²CHR³COO]₂Sn[R⁴]₂and [R¹GeCHR²CHR³COO]Sn[CH₂C(CH₃)]₃ have been synthesized by the reported methods and were studied by mass spectrometric analysis to explore their fragmentation pattern and formation of complexes as well. The spectral data indicates that these complexes undergo Maclafferty rearrangement during the fragmentation process. Another interesting feature observed was the formation of five membered germalactones, which may otherwise be formed by the classical synthetic routes. In diorganotin derivatives two fragmentation routes are observed. In route one, the loss of ligand takes place first and then loss of alkyl (R) group is observed. In second route, the loss of alkyl(R) group is followed by the loss of ligand. In germatranyl derivatives the base peak is always due to germatrane moiety reflecting its higher stability. Triorganotin derivatives of carboxylates containing germanium follow the same general pattern suggesting the primary decomposition of R group, followed by the removal of second R group and a loss of either carbon dioxide from ligand or of complete ligand. In most of the cases base peak is observed in triorganotin after the elimination of R group. The percentage abundance of major components was also compared. The fragment ions were in good agreement with the expected structure of the compounds.