| Abstract
| - The palladium-catalyzed Suzuki cross-coupling reaction of arylboronic acids and 6-bromo- and 6,8-dibromo-3,4-dihydropyrrolo[1,2-a]pyrazines afforded 6-substituted and 6,8-disubstituted 3,4-dihydropyrrolo[1,2-a]pyrazines in good yields. Stille and Negishi coupling reactions have been used toprepare 6-heteroaryl-substituted derivatives in moderate yields by employing heteroaryl halidesand 6-metalated 3,4-dihydropyrrolo[1,2-a]pyrazines as reaction partners. A variety of cyclicsecondary amines have also been incorporated at position C-6 of 6-bromo-1-phenyl-3,4-dihydropyrrolo[1,2-a]pyrazine in the presence of the palladium catalyst Pd2(dba)3 in conjunction with BINAPas ligand. This amination reaction is one of the few reported examples of such a palladium-catalyzedtransformation on a pyrrole ring, although the reaction could not be extended to less nucleophilicamines.
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