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DOI: 10.1055/s-2003-36245
The First Generation of Azulenyl-Lithium and -Magnesium: A Novel, Versatile Method of Introducing a Substituent at the 2-Position of an Azulene Skeleton
Publikationsverlauf
Publikationsdatum:
18. Dezember 2002 (online)
Abstract
1,3-Dihaloazulenes were effectively transformed into 2-substituted azulenes through lithiation at the 2-position by proton abstraction. Furthermore, 1,3-dichloro-2-iodoazulene was found to undergo iodine-lithium and -magnesium exchange to generate the corresponding azulenyl-lithium and -magnesium, respectively.
Key words
azulenes - lithium - magnesium - metalations - halogens
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References and Notes
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7The single point energies of azulenyl anion and its biradical species were calculated by using the Gaussian 98 Revision A.6 program [8] at UHF/6-31G** level, based on the geometries optimized by semiempirical AM1 calculations.
9The total energy of anion A was found to lie by about 11 kcal/mol above that of biradical B.