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Reducing GaH and GaC Bonds in Close Proximity to Oxidizing Peroxo Groups: Conflicting Properties in Single Molecules
Author(s) -
Uhl Werner,
Reza Halvagar Mohammad,
Claesener Michael
Publication year - 2009
Publication title -
chemistry – a european journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.687
H-Index - 242
eISSN - 1521-3765
pISSN - 0947-6539
DOI - 10.1002/chem.200900746
Subject(s) - adduct , oxidizing agent , chemistry , molecule , hydrogen peroxide , peroxide , oxygen , medicinal chemistry , lithium (medication) , hydrogen bond , decomposition , yield (engineering) , crystallography , stereochemistry , organic chemistry , materials science , medicine , metallurgy , endocrinology
Treatment of [Li(H 2 Ga{CH(SiMe 3 ) 2 } 2 )] ⋅ 2 OEt 2 ( 1⋅ 2 OEt 2 ) with two equivalents of tert ‐butyl hydrogen peroxide, H‐O‐O‐CMe 3 , afforded the organogallium peroxide [({(Me 3 Si) 2 HC} 2 Ga(OH)(OOCMe 3 )Li) 2 ] ( 3 ), which possesses oxidizing peroxo groups in close proximity to reducing GaC bonds. The lithium atoms of the dimeric formula units are coordinated by both oxygen atoms of the peroxides and by two hydroxo groups. The cleavage of the GaC bond was not observed, even when an excess of H‐O‐O‐CMe 3 was applied. Instead, the adduct [{(Me 3 Si) 2 HC} 2 Ga(OH)(OOCMe 3 ) 2 Li 2 (HOOCMe 3 )] ( 4 ) was isolated, which has an intact H‐O‐O‐CMe 3 molecule terminally attached to lithium. A similar structural motif was found for the compound [(LiOOCMe 3 ) 2 (HOOCMe 3 ) 2 ] ( 5 ). The trihydrido gallanate [Li(H 3 Ga{CH(SiMe 3 ) 2 })] ⋅ OEt 2 ( 2 ) yielded the unique peroxide [({(Me 3 Si) 2 HC}Ga(H)(OOCMe 3 ) 2 Li) 2 ] ( 6 ) under similar conditions that possesses GaC and even more reactive GaH bonds beside peroxo groups. It decomposed at room temperature by the insertion of oxygen atoms into the GaH bonds and the formation of [({(Me 3 Si) 2 HC}Ga(OH)(OCMe 3 )(OOCMe 3 )Li) 2 ] ( 7 ), which was isolated in a low yield. Further decomposition gave the complete degradation of all peroxo groups with the formation of a relatively complicated Li 4 Ga 4 O 8 cage ( 8 ).