Stereoselective Construction of Acyclic Structures with Four Consecutive Asymmetric Centers
نویسندگان
چکیده
منابع مشابه
construction of vector fields with positive lyapunov exponents
in this thesis our aim is to construct vector field in r3 for which the corresponding one-dimensional maps have certain discontinuities. two kinds of vector fields are considered, the first the lorenz vector field, and the second originally introced here. the latter have chaotic behavior and motivate a class of one-parameter families of maps which have positive lyapunov exponents for an open in...
15 صفحه اولAcyclic amino acid-catalyzed direct asymmetric aldol reactions: alanine, the simplest stereoselective organocatalyst.
The linear amino acid-catalyzed direct asymmetric intermolecular aldol reaction is presented; simple amino acids such as alanine, valine, isoleucine, aspartate, alanine tetrazole and serine catalyzed the direct catalytic asymmetric intermolecular aldol reactions between unmodified ketones and aldehydes with excellent stereocontrol and furnished the corresponding aldol products in up to 98% yiel...
متن کاملConstruction of highly enantioenriched spirocyclopentaneoxindoles containing four consecutive stereocenters via thiourea-catalyzed asymmetric Michael–Henry cascade reactions
The thiourea-catalyzed asymmetric synthesis of highly enantioenriched spirocyclopentaneoxindoles containing chiral amide functional groups using simple 3-substituted oxindoles and nitrovinylacetamide as starting materials was achieved successfully. This protocol features operational simplicity, high atom economy, and high catalytic asymmetry, thus representing a versatile approach to the synthe...
متن کاملAcyclic quaternary centers from asymmetric conjugate addition of alkylzirconium reagents to linear trisubstituted enones.
Synthetic methods for the selective formation of all carbon quaternary centres in non-cyclic systems are rare. Here we report highly enantioselective Cu-catalytic asymmetric conjugate addition of alkylzirconium species to twelve different acyclic trisubstituted enones. A variety of sp3-hybridized nucleophiles generated by in situ hydrozirconation of alkenes with the Schwartz reagent can be intr...
متن کاملSimultaneous and stereoselective construction of planar and axial centers of chirality.
Atropisomerism resulting from hindered rotation about single bonds can lead to molecules with centers of axial chirality and are widely used in asymmetric catalytic synthesis.1 Molecules containing planar centers of chirality have also been used as chiral ligands, particularly those containing η6-benzene and η5-cyclopentadienyl complexes.2 To our knowledge, there are no known synthetic methods ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Bulletin of the Chemical Society of Japan
سال: 1990
ISSN: 0009-2673,1348-0634
DOI: 10.1246/bcsj.63.1039