67113-14-8

Upstream product

• 24401-39-6 2-methyl-2-phenyl-pentenal 
• 591-50-4 iodobenzene 
• 509323-88-0 1-methyl-2-(S)-(2-methyl-cyclopent-1-enyloxymethyl)-pyrrolidine 
• 4413-14-3 1-phenyl-1-ethylidenecyclobutane 
• 1120-72-5 2-Methylcyclopentanone 
• 1198-34-1 2-Phenylcyclopentanone 
• 76430-23-4 2-methylcyclopentanone dimethyl acetal 

Relevant academic research and scientific papers

High stereoselectivity in chelation-controlled intermolecular Heck reactions with aryl chlorides, vinyl chlorides and vinyl triflates

Highly stereoselective chelation-controlled Pd(0)-catalyzed β-arylations and β-vinylations of a five-membered chiral, pyrrolidine-based vinyl ether were achieved using aryl- and vinyl chlorides as substrates, yielding quaternary 2-aryl/vinyl-2-methyl cyclopentanones in 89-96% ee under neutral reaction conditions. This journal is The Royal Society of Chemistry.

Enantiopure 2-aryl-2-methyl cyclopentanones by an asymmetric chelation-controlled Heck reaction using aryl bromides: increased preparative scope and effect of ring size on reactivity and selectivity

Quaternary 2-aryl-2-methyl cyclopentanones were obtained in 85-94% ee via Pd(0)-catalyzed chelation-controlled asymmetric arylation of a cyclopentenyl ether with aryl bromides and subsequent hydrolysis. Two new cyclohexenyl ethers were synthesized and evaluated as Heck substrates with both aryl iodides and bromides under different reaction conditions. Arylations of the six-membered vinyl ether 1-methyl-2-(S)-(cyclohex-1-enyloxymethyl)-pyrrolidine with aryl bromides were achieved with t-Bu3P-promoted palladium catalysis using either classical or microwave heating. Isolated Heck products were also obtained in high diastereoselectivities (94-98% de).

Enantioselective synthesis of 2-alkyl-2-aryl cyclopentanones by asymmetric epoxidation of tetrasubstituted cyclobutylidene olefins and epoxide rearrangement

This letter describes a highly enantioselective epoxidation of tetrasubstituted benzylidenecyclobutanes using glucose-derived ketone as catalyst and oxone as oxidant. The Et2AlCl promoted rearrangement of the resulting epoxides provides 2-alkyl

A new highly asymmetric chelation-controlled heck arylation

This communication describes the development of a new highly asymmetric chelation-controlled Heck arylation. The methodology permits formation of 2-aryl-2-methyl cyclopentanones in good to very good two-step yields (45-78%) with excellent chiral enrichmen

Enantioselective Synthesis of Polyfunctional Small Building Blocks with a Quaternary Stereogenic Center

Application of the SAMP-/RAMP-hydrazone method offers an efficient and flexible access to compounds with a quaternary stereogenic center.Examples bearning silyl, thio, phenyl, aldo, keto, ester, and alkyl functionalities are described.The 2-phenylaldehydes and -ketones and the β-keto esters 4 were obtained in good overall yields and with variable enantiomeric excesses.The synthesis of the thiolated 2-formyl and 3-formyl carboxylic esters 12 was achieved in high overall yields and with high enantiomeric excesses.The silylated carboxylic ester and acids 16 were produced in moderate to high overall yields and with moderate to excellent enantiomeric excesses, depending on the electrophile used for the quaternization.The absolute configurations of the compounds 12 and 16 were determined by X-ray structure analyses, and the mechanism of the quaternization is postulated. - Key Words: Asymmetric synthesis / SAMP,RAMP-Hydrazones

CATALYTIC DECARBONYLATION, HYDROACYLATION, AND RESOLUTION OF RACEMIC PENT-4-ENALS USING CHIRAL BIS(DITERTIARY-PHOSPHINE) COMPLEXES OF RHODIUM(I)

Attempts to decarbonylate racemic aldehydes catalytically using rhodium(I) complexes containing chiral di-tertiary-phosphine ligands are described.Incorporation of an alkenic moiety into the aldehyde, for subsequent probing of induced asymmetry by chiral shift reagents, leads instead to formation of optically active hydroacylated products via kinetic resolution of the precursor racemic aldehyde.For example, (RS)-2-methyl-2-phenylpent-4-enal (1a) yields, on treatment with Cl, 2-methyl-2-phenylcyclopentanone with up to 69percent e.e of the (-)-(S) optical isomer and remaining unreacted aldehyde which is possibly the enantiomerically pure (-)-(R) form.Extension of this cyclization reaction to a 3,3-disubstituted pent-4-enal similarly provides a synthesis for an optically active 3,3-disubstituted cyclopentanone.Decarbonylation by-products are also observed; those from 1a appear as E- and Z-2-phenylpent-2-ene.The cyclization of 1a is catalyzed also by Rh(chiraphos)(solvent)2+ but with lower e.e.