Lithium acetylides as alkynylating reagents for the enantioselective alkynylation of ketones catalyzed by lithium binaphtholate.

نویسندگان

  • Kana Tanaka
  • Kenji Kukita
  • Tomonori Ichibakase
  • Shunsuke Kotani
  • Makoto Nakajima
چکیده

Chiral lithium binaphtholate effectively catalyzed the enantioselective alkynylation of ketones using lithium acetylide as an alkynylating agent. This is the first example of the catalytic enantioselective addition of lithium acetylide to carbonyl compounds without the aid of other metal sources.

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

Enantioselective Evans-Tishchenko reduction of β-hydroxyketone catalyzed by lithium binaphtholate.

Lithium diphenylbinaphtholate catalyzed the enantioselective Evans-Tishchenko reduction of achiral β-hydroxyketones to afford monoacyl-protected 1,3-diols with high stereoselectivities. In the reaction of racemic β-hydroxyketones, kinetic optical resolution occurred in a highly stereoselective manner.

متن کامل

Chiral lithium binaphtholate aqua complex as a highly effective asymmetric catalyst for cyanohydrin synthesis.

A highly enantioselective cyanohydrin synthesis with aromatic aldehydes using chiral lithium binaphtholate aqua or alcohol complexes has been developed and is a simple and inexpensive catalyst suitable for process chemistry to give gram-scale cyanohydrins successfully. Dramatic improvements in enantiomeric excess have been realized along with an interesting changeover in absolute stereochemistr...

متن کامل

AMild Method for the Preparation of g-Hydroxy- a,b-Acetylenic Esters**

The alkynylation of a carbonyl compound is a powerful reaction for forming a carbon–carbon s bond. Highly functionalized g-hydroxy-a,b-acetylenic esters RCH(OH)C C CO2Me (A) are promising synthetic intermediates that can be used as precursors to a variety of complex molecules. Since the procedure was reported by Midland et al., alcohols A have mainly been prepared by the treatment of aldehydes ...

متن کامل

Efficient asymmetric synthesis of spiro-2(3H)-furanones via phase-transfer-catalyzed alkynylation.

Efficient asymmetric synthesis of spiro-2(3H)-furanones was achieved via phase-transfer-catalyzed highly enantioselective alkynylation of cyclic β-keto esters with hypervalent iodine reagents.

متن کامل

Synthesis of Lithium Ion Sieve Nanoparticles and Optimizing Uptake Capacity by Taguchi Method

Spinel-type of MnO2 nanoparticles which successfully synthesized by a hydrothermal process, have a required capacity for lithium uptake from liquid resources. Themost lithium adsorption capacity of 6.6 mmol/g of up to now was found to be an important limiting parameter for industrial applications. Therefore, increasing uptake capacity of these ion sieve...

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:
  • Chemical communications

دوره 47 19  شماره 

صفحات  -

تاریخ انتشار 2011