The Dewar Isomer of 1,2-Dihydro-1,2-azaborinines: Isolation, Fragmentation, and Energy Storage.
Angew Chem Int Ed Engl
; 57(19): 5296-5300, 2018 05 04.
Article
em En
| MEDLINE
| ID: mdl-29457683
ABSTRACT
The photochemistry of 1,2-dihydro-1,2-azaborinine derivatives was studied under matrix isolation conditions and in solution. Photoisomerization occurs exclusively to the Dewar valence isomers upon irradiation with UV light (>280â
nm) with high quantum yield (46 %). Further photolysis with UV light (254â
nm) results in the formation of cyclobutadiene and an iminoborane derivative. The thermal electrocyclic ring-opening reaction of the Dewar valence isomer back to the 1,2-dihydro-1-tert-butyldimethylsilyl-2-mesityl-1,2-azaborinine has an activation barrier of (27.0±1.2)â
kcal mol-1 . In the presence of the Wilkinson catalyst, the ring opening occurs rapidly and exothermically (ΔH=(-48±1)â
kcal mol-1 ) at room temperature.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Alemanha