Asymmetric induction reactions. II. Stereochemical studies on asymmetric (2,3) sigmatropic rearrangements using chiral ketenimines.
نویسندگان
چکیده
منابع مشابه
Recent Advances in Asymmetric [3,3]-Sigmatropic Rearrangements
Synthesis 2003, No. 7, Print: 20 05 2003. Art Id.1437-210X,E;2003,0,07,0961,1008,ftx,en;E08002SS.pdf. © Georg Thieme Verlag Stuttgart · New York Abstract: The synthesis of new complex structures is still a challenge in preparative organic chemistry. Focusing on the generation of defined stereogenic centers, the [3,3]-sigmatropic rearrangements are known as reliable reactions. Always, a highly o...
متن کاملAsymmetric reactions on chiral catalysts entrapped within a mesoporous cage.
The encapsulation of homogeneous chiral catalysts, e.g. Co(Salen) and Ru-TsDPEN, in the mesoporous cage of SBA-16 is demonstrated; the encapsulated catalysts show performance as good as that of the homogeneous catalysts, and can be recycled for more than 10 times without significant loss of catalytic performance.
متن کاملDioxirane mediated asymmetric epoxidations: stereochemical studies via isotopic labeling.
A study, via isotopic labeling, of the stereoselective processes in a Shi-type epoxidation, has revealed that the chiral platform provided by the catalyst mediates the transfer of the pro-S "O" of the related dioxirane species to the alkene in a doubly stereoselective manner.
متن کاملAxially chiral imidodiphosphoric Acid catalyst for asymmetric sulfoxidation reaction: insights on asymmetric induction.
Insights into chiral induction for an asymmetric sulfoxidation reaction involving a single oxygen atom transfer are gained through analyzing the stereocontrolling transition states. The fitting of the substrate into the chiral cavity of a new class of imidodiphosphoric Brønsted acids, as well as weak CH⋅⋅⋅π and CH⋅⋅⋅O noncovalent interactions, are identified as responsible for the observed ch...
متن کاملChiral Lewis acid-catalyzed asymmetric Baylis-Hillman reactions.
An effective chiral Lewis acid-catalyzed asymmetric Baylis-Hillman reaction is described. Good to high enantioselectivities were obtained using 3 mol % chiral catalyst. Novel camphor-derived dimerized ligands were prepared from the condensation of (+)-ketopinic acid with the corresponding diamines and hydrazine under acidic conditions. When alpha-naphthyl acrylate was used as a Michael acceptor...
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: Chemical and Pharmaceutical Bulletin
سال: 1985
ISSN: 0009-2363,1347-5223
DOI: 10.1248/cpb.33.4691