Highly Enantio- and Diastereoselective Hetero-Diels-Alder Reactions Catalyzed by New Chiral Tridentate Chromium(III) Catalysts
摘要:
Even moderately nucleophilic dienes react with simple aldehydes in the presence of a new Cr(III) catalyst in a hetero-Diels-Alder reaction [Eq. (1)]. Tetrahydropyranyl products with up to three stereogenic centers are generated in near-perfect diastereoselectivities and with greater than 90 % ee (99 % ee for the example shown). TBAF=tetrabutylammonium fluoride; TBS=tert-butyldimethylsilyl; TES=triethylsilyl.
The present invention relates to a process for stereoselective cycloaddition reactions which generally comprises a cycloaddition reaction between a pair of substrates, each either chiral or prochiral, that contain reactive &pgr;-systems, in the presence of a non-racemic chiral catalyst, to produce a stereoisomerically enriched product. The present invention also relates to novel asymmetric catalyst complexes comprising a metal and an asymmetric tridentate ligand.
Rhodium‐Catalyzed Enantioselective [4+2] Cycloadditions of Vinylcarbenes with Dienes
作者:Bowen Zhang、Huw M. L. Davies
DOI:10.1002/anie.201914354
日期:2020.3.16
The reaction of 2-siloxycyclo-1,3-dienes with E-vinyldiazoacetates in the presence of the bulky chiral dirhodium tetracarboxylate catalyst, Rh2 (R-p-PhTPCP)4 results in an enantioselective [4+2] cycloaddition, in which three new stereogenic centers are formed. The [4+2] cycloadducts are generated as single diastereomers with high enantiocontrol (95-98 % ee). When the diene contains an additional stereogenic
[EN] CATALTYTIC ASYMMETRIC HETERO DIELS-ALDER REACTION OF A HETEROAROMATIC C-NITROSO DIENOPHILE: A NOVEL METHOD FOR SYNTHESIS OF CHIRAL NON-RACEMIC AMINO ALCOHOLS<br/>[FR] REACTION HETERO DIELS-ALDER IMPLIQUANT UN DIENOPHILE C-NITROSO HETEROAROMATIQUE : NOUVEAU PROCEDE DE SYNTHESE D'AMINO-ALCOOLS NON RACEMIQUES CHIRAUX
申请人:UNIV CHICAGO
公开号:WO2005068457A1
公开(公告)日:2005-07-28
The present invention is directed to a catalytic asymmetric C-nitroso Diels-Alder reaction.
本发明涉及一种催化不对称C-亚硝基Diels-Alder反应。
Design of Chiral <i>N</i>-Triflyl Phosphoramide as a Strong Chiral Brønsted Acid and Its Application to Asymmetric Diels−Alder Reaction
作者:Daisuke Nakashima、Hisashi Yamamoto
DOI:10.1021/ja062508t
日期:2006.8.1
A highly reactive and acidic chiral Brønsted acid catalyst, chiral N-triflyl phosphoramide, was developed. Highly enantioselective Diels-Alderreaction of alpha,beta-unsaturated ketone with silyloxydiene was demonstrated using this chiral Brønsted acid catalyst.
Chiral Phosphoric Acid-Governed Anti-Diastereoselective and Enantioselective Hetero-Diels−Alder Reaction of Glyoxylate
作者:Norie Momiyama、Hideaki Tabuse、Masahiro Terada
DOI:10.1021/ja904749x
日期:2009.9.16
A highly enantioselective anti-diastereoselective hetero-Diets-Alder reaction between a glyoxylate and siloxy- or methoxydienes using a chiral phosphoric acid catalyst that possesses less bulky phenyl groups at the 3 and 3' positions of binaphthyl has been developed. The diastereoselectivities presented are disparate to those previously reported for hetero-Diets-Alder reactions catalyzed by a chiral Lewis acid.