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Struktur der Blei(IV)‐carboxylate und ihre Zersetzung über elektronenspinresonanz‐spektroskopisch nachweisbare Radikalzwischenstufen
Author(s) -
Heusler K.,
Loeliger H.
Publication year - 1969
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19690520610
Subject(s) - chemistry , carboxylate , decarboxylation , radical , alkyl , carbonium ion , benzene , photochemistry , covalent bond , hydrogen atom abstraction , oxygen , medicinal chemistry , polymer chemistry , ion , stereochemistry , organic chemistry , catalysis
The position of the asymmetric COO‐ vibration of lead 4+ carboxylates (at 6.50 to 6.58 μ) clearly indicates the absence of covalent bonding between oxygen and lead. These salts show strong UV. absorption in the region of 220 to 270 nm which is assigned to a charge transfer from oxygen to lead. UV.‐irradiation of lead 4+ carboxylates at −196°C in a solid benzene matrix leads to decarboxylation and production of alkyl radicals which were identified by ESR. spectrometry. These radicals react in the solid matrix by hydrogen abstraction from the α‐position of a neighbouring carboxylate. In solution however rapid oxidation to carbonium ions occurs.