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Enantioselective and Enantiospecific Transition-Metal-Catalyzed Cross-Coupling Reactions of Organometallic Reagents To Construct C-C Bonds.

Cherney AH, Kadunce NT, Reisman SE - Chem. Rev. (2015)

View Article: PubMed Central - PubMed

Affiliation: The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.

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reagents in asymmetric alkyl cross-coupling reactions, with Hayashi, a single example of an asymmetric cross-coupling between sec-alkyl organic halides and organosilicon reagents has been reported stereoconvergent cross-coupling reactions between sec-alkyl electrophiles and either C(sp)- or C(sp)-hybridized organometallic reagents, Sestelo, Sarandeses, (Scheme 9a)... This result and π-allylmetal complex... Unselective reductive selectivity for the (Z)-alkene in most cases; MeMgBr resulted in decreased regioselectivity... increasing the C1–C1′ separation and disfavoring 1,1′ reductive elimination... use in asymmetric allylic alkylation reactions: any successful transformations the allenylmetal and its isomeric propargylmetal species prior to reductive elimination... the analogous asymmetric cross-coupling reactions of tert-alkyl partners represent a largely undeveloped area of great synthetic

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AsymmetricNegishi cross-coupling of α-halo ketones.
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fig18: AsymmetricNegishi cross-coupling of α-halo ketones.

Mentions: Prior to their disclosure of theenantioselective cross-couplingbetween α-bromo ketones and aryl Grignard reagents (see Figure 13), the Fu laboratorydeveloped a Ni/L42-catalyzed asymmetric cross-couplingof α-bromo ketones and arylzinc reagents (Figure 18a).70 The low basicity of the organozinc reagent, as well as a reducedreaction temperature, accounts for the configurational stability ofthe potentially sensitive tertiary stereocenter in 42. The synthesis of dialkyl ketones proceeded with lower enantioinduction;however, this substrate limitation is addressed by their subsequentlydeveloped Kumada–Corriu conditions.69 A recent modification of the reaction conditions has permitted theuse of α-halo-α-fluoro ketones, enabling the asymmetricformation of tertiary fluorides (Figure 18b).86


Enantioselective and Enantiospecific Transition-Metal-Catalyzed Cross-Coupling Reactions of Organometallic Reagents To Construct C-C Bonds.

Cherney AH, Kadunce NT, Reisman SE - Chem. Rev. (2015)

AsymmetricNegishi cross-coupling of α-halo ketones.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4566132&req=5

fig18: AsymmetricNegishi cross-coupling of α-halo ketones.
Mentions: Prior to their disclosure of theenantioselective cross-couplingbetween α-bromo ketones and aryl Grignard reagents (see Figure 13), the Fu laboratorydeveloped a Ni/L42-catalyzed asymmetric cross-couplingof α-bromo ketones and arylzinc reagents (Figure 18a).70 The low basicity of the organozinc reagent, as well as a reducedreaction temperature, accounts for the configurational stability ofthe potentially sensitive tertiary stereocenter in 42. The synthesis of dialkyl ketones proceeded with lower enantioinduction;however, this substrate limitation is addressed by their subsequentlydeveloped Kumada–Corriu conditions.69 A recent modification of the reaction conditions has permitted theuse of α-halo-α-fluoro ketones, enabling the asymmetricformation of tertiary fluorides (Figure 18b).86

View Article: PubMed Central - PubMed

Affiliation: The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States.

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

reagents in asymmetric alkyl cross-coupling reactions, with Hayashi, a single example of an asymmetric cross-coupling between sec-alkyl organic halides and organosilicon reagents has been reported stereoconvergent cross-coupling reactions between sec-alkyl electrophiles and either C(sp)- or C(sp)-hybridized organometallic reagents, Sestelo, Sarandeses, (Scheme 9a)... This result and π-allylmetal complex... Unselective reductive selectivity for the (Z)-alkene in most cases; MeMgBr resulted in decreased regioselectivity... increasing the C1–C1′ separation and disfavoring 1,1′ reductive elimination... use in asymmetric allylic alkylation reactions: any successful transformations the allenylmetal and its isomeric propargylmetal species prior to reductive elimination... the analogous asymmetric cross-coupling reactions of tert-alkyl partners represent a largely undeveloped area of great synthetic

No MeSH data available.


Related in: MedlinePlus