title: Binap-gold(I) versus Binap-silver trifluoroacetate complexes as catalysts in 1,3-dipolar cycloadditions of azomethine ylides.
abstract: The 1,3-dipolar cycloaddition between azomethine ylides and alkenes is efficiently catalysed by [{(S(a))-Binap-Au(tfa)}(2)] (Binap=2,2'-bis(diphenylphosphino)-1,1'-binaphthyl; tfa=trifluoroacetyl). Maleimides, 1,2-bis(phenylsulfonyl)ethylene, chalcone and nitrostyrene were suitable dipolarophiles even when using sterically hindered 1,3-dipole precursors. The results obtained in these transformations improve the analogous ones obtained in the same reactions catalysed by [Binap-Ag(tfa)]. In addition, computational studies have also been carried out to demonstrate both the high enantioselectivity exhibited by the chiral gold(I) complex, and the non-linear effect observed in this transformation.
authors: Química Orgánica e Instituto de Síntesis Orgánica, Universidad de Alicante, Apdo 99, 03080 Alicante, Spain.
authors: María
authors: M
authors: Martín-Rodríguez
authors: Carmen
authors: C
authors: Nájera
authors: José M
authors: JM
authors: Sansano
authors: Abel
authors: A
authors: de Cózar
authors: Fernando P
authors: FP
authors: Cossío