Organocatalyzed highly stereoselective Michael addition of ketones to alkylidene malonates and nitroolefins using chiral primary-secondary diamine catalysts based on bispidine.

نویسندگان

  • Jie Liu
  • Zhigang Yang
  • Xiaohua Liu
  • Zhen Wang
  • Yanling Liu
  • Sha Bai
  • Lili Lin
  • Xiaoming Feng
چکیده

Organocatalysts containing primary-secondary diamines based on bispidine have been developed to catalyze the asymmetric Michael addition of ketones to alkylidene malonates and nitroalkenes. The corresponding products were obtained in high yields (up to 99%) with high diastereoselectivities (up to 99:1) and high enantioselectivities (up to 97% ee) under mild conditions using either environmentally benign water as the solvent or no solvent.

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

Cinchona alkaloid-based chiral catalysts act as highly efficient multifunctional organocatalysts for the asymmetric conjugate addition of malonates to nitroolefins.

New pentaerythritol tetrabromide-based chiral quaternary ammonium salts acting as organocatalysts (7a and 7b) have been prepared and used as organocatalysts for enantioselective Michael addition reactions between various nitroolefins and Michael donors (malonates) under mild reaction conditions, such as lower concentration of base and catalyst and room temperature, with very good chemical yield...

متن کامل

Catalytic enantioselective direct Michael additions of ketones to alkylidene malonates

Enantioselective direct Michael additions of ketones using (S)-1-(2-pyrrolidinylmethyl)-pyrrolidine as a catalyst are described. Michael adducts with up to 91% e.e. were obtained by the reaction of alkylidene malonates with simple unactivated ketones under mild reaction conditions. © 2001 Elsevier Science Ltd. All rights reserved. An increasing demand for optically active compounds has stimulat...

متن کامل

Catalytic Direct Asymmetric Michael Reactions: Addition of Unmodified Ketone and Aldehyde Donors to Alkylidene Malonates and Nitro Olefins Catalytic Direct Asymmetric Michael Reactions

SYNTHESIS 2004, No. 9, pp 1509–1521xx.xx.2004 Advanced online publication: 26.05.2004 DOI: 10.1055/s-2004-822392; Art ID: C0404SS © Georg Thieme Verlag Stuttgart · New York Abstract: The Michael additions of a number of ketones and aldehydes to alkylidene malonates and nitro olefins were studied. The reactions employ small organic molecules as catalyst under mild reaction conditions and do not ...

متن کامل

Chiral guanidine-catalyzed asymmetric direct vinylogous Michael reaction of α,β-unsaturated γ-butyrolactams with alkylidene malonates.

The asymmetric direct vinylogous Michael reaction of α,β-unsaturated γ-butyrolactams with alkylidene malonates has been developed. Various 5-substituted 3-pyrrolidin-2-ones were obtained in high yields (up to 93%) with excellent stereoselectivities (up to 94% ee, 95 : 5 dr), using a novel bifunctional C(1)-symmetric guanidine organocatalyst embodied a secondary amine subunit.

متن کامل

Chiral phosphoproline-catalyzed asymmetric Michael addition of ketones to nitroolefins: an experimental and theoretical study.

A novel pyrrolidine-based chiral phosphoproline is an effective bifunctional organocatalyst for the asymmetric Michael addition of ketones to nitroolefins giving high levels of diastereo- and enantio-selectivities (up to > 99 : 1 dr and 96% ee). anti-SR Transition state has the lowest barrier which controls the stereoselectivity, in agreement with experimental results.

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:
  • Organic & biomolecular chemistry

دوره 7 19  شماره 

صفحات  -

تاریخ انتشار 2009