Adição nucleofílica em alilaminas promovida por complexos de paládio (II)

Abstract

o presente trabalho relata o estudo das reações de carbo- e alcoxipaladação de olefinas funcionalizadas. Para tal propósito, foram sintetizadas as alilaminas 4,N,N-dibenzilamino-5-metilexen-2-enoato de metila (138), 3,N,N-dibenzilaminoprop-l-eno (111) e 3,N,N-(R,R)-α,α-dimetildibenzilaminoprop-l-eno(114). A alilamina (138), desativada pelo grupo carbóxi, e a alilamina (114), devido a presença dos grupos volumosos dimetildibenzil ligados ao nitrogênio, não sofrem adição nucleofílica, na presença de sais de paládio (II). Entretanto, a alilamina (111), na presença de PdCl2(PhCN) 2 e carboxilatos, produz seletivamente complexos paladociclos de cinco membros.

We present the synthesis of chiral and achiral allylic amines derived from α-amino acids. The carbo- and alcoxy-palladation of these allylic amines have been investigated. The allylic amine methyl 4,N,N-dibenzylamino-5-methylhexen-2-enoate (138), desactivated by carboxy groups, and the allylic amine 3,N,N-(R,R)-α,αdimethyldibenzylaminoprop-l-ene (114), with the bulky group α,α-dimethyldibenzyl attached at amino group, did not undergo nucleophilic additions, in the presence of Pd(II) salts. However, the 3,N,N-dibenzylaminoprop-l-ene (111), in the presence of PdCl2(PhCN)2 and carboxilates, produces selectively five-membered palladocyclic complexes.