Asymmetric [2,3]-sigmatropic rearrangement of allylic ammonium ylides.
نویسندگان
چکیده
An asymmetric Lewis acid-mediated [2,3]-sigmatropic rearrangement of allylic amines has been developed, affording the corresponding homoallylic amines in good yield and excellent enantioselectivities. The rearrangement proceeds by complexation of the chiral Lewis acid to the amine followed by deprotonation and rearrangement.
منابع مشابه
An isothiourea-catalyzed asymmetric [2,3]-rearrangement of allylic ammonium ylides.
Benzotetramisole promotes the catalytic asymmetric [2,3]-rearrangement of allylic quaternary ammonium salts (either isolated or prepared in situ from p-nitrophenyl bromoacetate and the corresponding allylic amine), generating syn-α-amino acid derivatives with excellent diastereo- and enantioselectivity (up to >95:5 dr; up to >99% ee).
متن کاملDynamics and a Unified Understanding of Competitive [2,3]- and [1,2]-Sigmatropic Rearrangements Based on a Study of Ammonium Ylides
The [2,3]- and [1,2]-sigmatropic rearrangements of ammonium ylides are studied by a combination of experimental, standard computational, and dynamic trajectory methods. The mixture of concerted [2,3] rearrangement and bond cleavage observed experimentally is accounted for by the outcome of trajectories passing through the formal [2,3] rearrangement transition state. In this way the bond cleavag...
متن کاملCatalytic asymmetric [2,3] sigmatropic rearrangement of sulfur ylides generated from carbenoids and propargyl sulfides
Catalytic asymmetric [2,3] sigmatropic rearrangement of sulfur ylides generated from aryldiazoacetates and propargyl sulfides with a number of chiral Rh(II) and Cu(I) catalysts have been investigated and moderately high enantioselectivities (up to 81% ee) have been achieved. © 2003 Elsevier Science Ltd. All rights reserved.
متن کاملCatalytic asymmetric [2,3]-sigmatropic rearrangement of sulfur ylides generated from copper(I) carbenoids and allyl sulfides.
Catalytic asymmetric sulfur ylide [2,3]-sigmatropic rearrangement of carbenoids generated from aryldiazoacetates has been investigated with a number of chiral Rh(II) and Cu(I) catalysts, and moderately high enantioselectivity (52-78% ee) can be achieved with Cu(MeCN)(4)PF(6)/2,2'-isopropylidenebis[(4S)-4-tert-butyl-2-oxazoline].
متن کاملAsymmetric Enzymatic Synthesis of Allylic Amines: A Sigmatropic Rearrangement Strategy.
Sigmatropic rearrangements, while rare in biology, offer opportunities for the efficient and selective synthesis of complex chemical motifs. A "P411" serine-ligated variant of cytochrome P450(BM3) has been engineered to initiate a sulfimidation/[2,3]-sigmatropic rearrangement sequence in whole E. coli cells, a non-natural function for any enzyme, providing access to enantioenriched, protected a...
متن کاملذخیره 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 ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 127 26 شماره
صفحات -
تاریخ انتشار 2005