Binap-gold(I) versus Binap-silver trifluoroacetate complexes as catalysts in 1,3-dipolar cycloadditions of azomethine ylides.

نویسندگان

  • María Martín-Rodríguez
  • Carmen Nájera
  • José M Sansano
  • Abel de Cózar
  • Fernando P Cossío
چکیده

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.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Complexes of Gold(I) with a Chiral Diphosphine Ligand: A Polymer with Both Au···Ag and Ag···Ag Metallophilic Bonds

Dedicated to Professor Hubert Schmidbaur, the grand master of gold chemistry, on the occasion of his 75th birthday The chemistry of gold(I) with the ligand binap = 2,2′-bis(diphenylphosphino)-1,1′ -binaphthyl is reported. Reaction of [Au2Cl2(μ-binap)] with silver trifluoroacetate gave the corresponding complex [Au2(O2CCF3)2(μ-binap)], and crystallization in the presence of excess silver trifluo...

متن کامل

Au(I)-catalyzed enantioselective 1,3-dipolar cycloadditions of münchnones with electron-deficient alkenes.

Synthetic methods relying on gold complexes as catalysts have recently been the focus of intense development.1 Despite numerous advances, relatively few enantioselective gold-catalyzed transformations have been described. The earliest example of an enantioselective gold(I)-catalyzed transformation, the Hayashi-Ito aldol reaction, was proposed to rely on activation of the nucleophile as a chiral...

متن کامل

Chiral gold(I) vs chiral silver complexes as catalysts for the enantioselective synthesis of the second generation GSK-hepatitis C virus inhibitor

The synthesis of a GSK 2(nd) generation inhibitor of the hepatitis C virus, by enantioselective 1,3-dipolar cycloaddition between a leucine derived iminoester and tert-butyl acrylate, was studied. The comparison between silver(I) and gold(I) catalysts in this reaction was established by working with chiral phosphoramidites or with chiral BINAP. The best reaction conditions were used for the tot...

متن کامل

Asymmetric 1,3-dipolar cycloadditons of stabilized azomethine ylides with nitroalkenes.

This review highlights the biological importance of many polysubstituted nitro-prolines and -pyrrolidines. Their preparation using asymmetric 1,3-dipolar cycloadditions of azomethine ylides with nitroalkenes using diastereoselective and enantioselective strategies is described remarking the scope and main features of each one.

متن کامل

1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides with Carbonyl Dipolarophiles Yielding Oxazolidine Derivatives.

We provide a comprehensive account of the 1,3-dipolar cycloaddition reactions of azomethine ylides with carbonyl dipolarophiles. Many different azomethine ylides have been studied, including stabilized and non-stabilized ylides. Of the carbonyl dipolarophiles, aldehydes including formaldehyde are the most studied, although there are now examples of cycloadditions with ketones, ketenes and carbo...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Chemistry

دوره 17 50  شماره 

صفحات  -

تاریخ انتشار 2011