Facile isomerization of silyl enol ethers catalyzed by triflic imide and its application to one-pot isomerization–(2 + 2) cycloaddition

نویسندگان

  • Kazato Inanaga
  • Yu Ogawa
  • Yuuki Nagamoto
  • Akihiro Daigaku
  • Hidetoshi Tokuyama
  • Yoshiji Takemoto
  • Kiyosei Takasu
چکیده

A triflic imide (Tf(2)NH) catalyzed isomerization of kinetically favourable silyl enol ethers into thermodynamically stable ones was developed. We also demonstrated a one-pot catalytic reaction consisting of (2 + 2) cycloaddition and isomerization. In the reaction sequence, Tf(2)NH catalyzes both of the reactions.

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

Formal (3+3) cycloaddition of silyl enol ethers catalyzed by trifric imide: domino Michael addition-claisen condensation accompanied with isomerization of silyl enol ethers.

We describe here a Tf₂NH-catalyzed formal (3+3) cycloaddition of silyl enol ethers with acrylates as a new domino reaction. In the domino sequence, the catalyst activates Michael addition, deprotonation of the resulting silyloxonium cation and intramolecular Claisen condensation. It was found that reaction modes significantly depend on the reaction temperature. We also examined the mechanistic ...

متن کامل

Pd-catalyzed reaction of aryl halides and propargyl furylmethyl ethers: a novel pathway to functionalized dihydroisobenzofurans.

An interesting sequential reaction involving Sonogashira coupling, propargyl-allenyl isomerization, intramolecular [4 + 2] cycloaddition, and bridged oxa-ring opening has been realized, providing a facile method for the synthesis of functionalized dihydroisobenzofurans from easily accessible starting materials with a decent diastereoselectivity.

متن کامل

Stereoselective synthesis of enynones via base-catalyzed isomerization of 1,5-disubstituted-2,4-pentadiynyl silyl ethers or their alcohol derivatives.

1,5-Disubstituted-2,4-pentadiynyl silyl ethers undergo smooth desilylative isomerization to afford cis-enynones as major products with moderate stereoselectivities in the presence of a catalytic amount of KO(t)Bu or DBU. While the isomerization reactions of their alcohol derivatives catalyzed by KOH, KO(t)Bu or NaH take place efficiently to produce trans-enynones with high stereoselectivities. ...

متن کامل

In situ generation of Mes2Mg as a non-nucleophilic carbon-centred base reagent for the efficient one-pot conversion of ketones to silyl enol ethers.

Treatment of commercially available MesMgBr with 1,4-dioxane produces the key Mes(2)Mg reagent in situ which then mediates the deprotonation of ketones to deliver trimethylsilyl enol ethers, at readily accessible temperatures and without any nucleophilic addition, in an expedient and high yielding one-pot process.

متن کامل

Palladium-catalyzed enantioselective cyclization of silyloxy-1,6-enynes.

Transition-metal-catalyzed cycloisomerization and cyclization reactions of enynes have emerged as powerful methods for the construction of heteroand carbocyclic compounds.1 More recently, enantioselective cycloisomerization of 1,6and 1,7-enynes has been employed in the preparation of enantioenriched 1,4-diene containing structures.2-4 Despite its potential utility, the related enantioselective ...

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:

دوره 8  شماره 

صفحات  -

تاریخ انتشار 2012