1228457-75-7

Upstream product

• 1228457-63-3 C₂₃H₃₃NO₄Si 
• 1228457-53-1 (E)-2-(tert-butyldimethylsilyl)oxy-3-methyl-4-phenylbut-3-enenitrile 
• 1895-97-2 2-methyl-3-phenylacrylic acid 
• 35086-87-4 (E)-2-methyl-3-phenylacryloyl chloride 
• 609-08-5 Diethyl methylmalonate 
• 7042-33-3 ethyl (E)-2-methyl-3-phenyl-2-propenoate 
• 2985-33-3 monoethyl methylmalonate 

Downstream Products

• 1228457-89-3 ethyl (1S,5S)-3-hydroxy-1,4-dimethyl-2-oxo-5-phenylcyclopent-3-enecarboxylate 

Relevant academic research and scientific papers

Enantioselective palladium(0)-catalyzed nazarov-type cyclization

A Pd0-catalyzed asymmetric Nazarov-type cyclization is described. The optimized ligand for the reaction incorporates a weakly coordinating pyridine ring into a TADDOL-derived phosphoramidite (TADDOL=α,α,α,α-tetraaryl-1,3-dioxolane-4,5-dimethanol). The reaction leads to the formation of cyclopentenones as single diastereoisomers that incorporate two contiguous asymmetric centers, one tertiary and one an all-carbon-atom quaternary stereocenter, in high yield and optical purity. It is noteworthy that the reaction does not require that substrates should be activated by aryl substituents.

Neutral nazarov-type cyclization catalyzed by palladium(0)

Joining the circle: The first Pd0 catalyzed Nazarov-type cyclization of diketoesters (see scheme) proceeds in 70 % to 95 % yield under strictly neutral pH conditions. Aryl substitution of the diketoesters is not required, so the reaction shows great versatility and can also proceed with aliphatic substrates. Copyright

An organocatalytic asymmetric nazarov cyclization

An organocatalytic asymmetric Nazarov cyclization of diketoesters that proceeds by means of a dual activation mechanism has been developed. Screening of a number of catalysts led to a new thiourea that incorporates a primary amino group. The method gives rise to cyclic products with two adjacent quaternary asymmetric carbon atoms, one of which is an all-carbon stereocenter, with complete or nearly complete diastereoselectivity and in high or very high enantiomeric excess. A brief and very convenient synthesis of the acyclic diketoester starting materials through nucleophilic addition to a ketene is also described.