Amin-Additionen an μ-(1,2-Diisocyanobenzol)-bis(chlorogold): Reaktionsbeteiligung der Isocyan-Nachbarfunktion und [Au]C-Übertragung

Abstract μ-(1,2-Diisocyanobenzene)bis(chlorogold) ( 2 ) reacts with 1,2-diaminobenzene ( 1 2 to give benzimidazolin-2-ylidene(chloro)gold ( 3 ) as the only reaction product, while 1 1 -mixtures of 3 and the corresponding diaminocarbene complexes ( 4 , 6 ) result from the reactions of 2 with 1,8-diaminonaphthalene or two equivalents of aniline. With one equivalent of a primary amine (MeNH 2 , PhNH 2 ), however, the isocyanide complexes Au(C1)CNR (R = Me, Ph) are obtaained, again together with 3 . Mechanistic key steps following the primary nucleophilic attack by the amine are a novel NC-coupling of the two neighbouring isocyano functions to give a benzimidazole ring system, and the transfer of the exocyclic Au(CI)C fragment onto the incoming amine. Accordingly, the reactions between 2 and secondary amines 2 and secondary amines lead to an isolable binuclear intermediate C ′ ( 1 1 ) or to the carbene complexes Au(Cl){C(NR 2 ) 2 } ( 8 , 2R = (CH 2 ) 5 ; 9 , 2R = (CH 2 ) 2 O(CH 2 ) 2 ; 10 , R = Me; 11 , 2R = (CH 2 ) 4 ) ( 1 2 ), respectively. 7 and morpholine give 3 and the asymmetrical diaminocarbene complex Au(Cl){C[ N(CH 2 ) 4 C H 2 ][ N(CH 2 ) 2 OCH 2 C H 2 ] } ( 12 ).