γ-Selective directed catalytic asymmetric hydroboration of 1,1-disubstituted alkenes.

نویسندگان

  • Sean M Smith
  • Gia L Hoang
  • Rhitankar Pal
  • Mohammad O Bani Khaled
  • Liberty S W Pelter
  • Xiao Cheng Zeng
  • James M Takacs
چکیده

Directed catalytic asymmetric hydroborations of 1,1-disubstituted alkenes afford γ-dioxaborato amides and esters in high enantiomeric purity (90-95% ee).

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

Synthesis of Secondary and Tertiary Alkylboranes via Formal Hydroboration of Terminal and 1,1-Disubstituted Alkenes.

Copper-catalyzed functionalization of terminal or 1,1-disubstituted alkenes with bis(pinacolato)diboron and methanol provides formal hydroboration products with exceptional regiocontrol favoring the branched isomer. Pairing this procedure with photocatalytic cross-couplings using iridium and nickel cocatalysis provides an effective, highly regioselective procedure for the hydroarylation of term...

متن کامل

New catalytic asymmetric strategies to access chiral aldehydes.

The present article describes the recent catalytic asymmetric methods developed in our group to access enantioenriched chiral aldehydes. We are generally aiming at developing complementary strategies based on either homogeneous organometallic catalysts or amino-catalysts and sometimes on a combination of both. Recent successes comprise a perfectly redox-economical iridium-catalyzed asymmetric ...

متن کامل

Palladium catalyzed cyclizations of oxime esters with 1,1-disubstituted alkenes: synthesis of α,α-disubstituted dihydropyrroles and studies towards an asymmetric protocol.

We report efficient Pd-catalyzed cyclizations of oxime esters with 1,1-disubstituted alkenes as the basis of a general entry to α,α-disubstituted pyrrolidine derivatives. We also demonstrate that catalytic asymmetric variants of this chemistry are feasible by employing a suitable chiral ligand.

متن کامل

Remarkably Facile Borane-Promoted, Rhodium-Catalyzed Asymmetric Hydrogenation of Tri- and Tetrasubstituted Alkenes

Oxime-directed catalytic asymmetric hydroboration is diverted to catalytic asymmetric hydrogenation (CAH) upon the addition of a proton source, such as MeOH, or by running the reaction under a hydrogen atmosphere. A borane (e.g., pinacolborane) is required to promote CAH. Tri- and tetrasubstituted alkenes, including the challenging all-alkyl tetrasubstituted alkenes, undergo CAH with enantiomer...

متن کامل

N,N-Dimethylaminobenzoates enable highly enantioselective Sharpless dihydroxylations of 1,1-disubstituted alkenes.

A design scenario aimed at exploring beneficial catalyst-substrate π-π stacking electronic interactions in the classical Sharpless asymmetric dihydroxylations (SAD) leads to the identification of highly polarizable allylic N,N-dimethylaminobenzoate as a remarkably efficient auxiliary for inducing high levels of enantioselectivities (up to 99% ee) in the traditionally challenging substrate class...

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 48 100  شماره 

صفحات  -

تاریخ انتشار 2012