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Qualitative Identification of Carboxylic Acids, Boronic Acids, and Amines Using Cruciform Fluorophores
Published on: August 19, 2013
Acoplamiento asimétrico carbono-carbono de fenoles o anilinas con triacetatos de arilplomo
Taichi Kano1, Yuki Ohyabu, Susumu Saito
1Contribution from the Graduate School of Engineering, Nagoya University, SORST, Japan.
Journal of the American Chemical Society
|May 9, 2002
Resumen
Este estudio detalla el acoplamiento asimétrico de fenoles y anilinas utilizando aminas quirales y reactivos organometálicos. Los métodos desarrollados producen eficientemente compuestos de poliarilo axialmente quirales a bajas temperaturas con alta selectividad.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis asimétrica de síntesis.
- La catálisis de la catálisis.
Sus antecedentes:
- Los compuestos biarílicos axialmente quirales son bloques de construcción cruciales en varios campos.
- Desarrollar métodos eficientes y selectivos para su síntesis sigue siendo un desafío.
Objetivo del estudio:
- Para investigar el acoplamiento asimétrico de derivados de fenol y anilina con triacetatos de arilplomo.
- Desarrollar métodos eficientes para la síntesis de diversos compuestos de poliarilo axialmente quirales.
Principales métodos:
- Utilizó aminas ópticamente activas (estricnina, brucina) como auxiliares quirales.
- Se emplean aminas terciarias conformacionalmente restringidas, aryloxuros de litio y tamices moleculares para el acoplamiento de fenol.
- Magnesio aplicado para el acoplamiento de anilina con triacetatos de arilplomo.
Principales resultados:
- Se logra una alta diastereoselectividad y enantioselectividad en el acoplamiento de fenol a bajas temperaturas (-40 a -20 °C).
- Magnesio establecido como una técnica clave para el acoplamiento de anilina.
- Sintetizó con éxito una amplia gama de compuestos di-, tri- y poliariles con quiralidad axial.
Conclusiones:
- Desarrolló métodos robustos y selectivos para la síntesis asimétrica de compuestos de poliarilo axialmente quirales.
- Los compuestos sintetizados son valiosos precursores para ligandos metálicos, productos naturales y polímeros helicoidales.
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01:28Structures of Carboxylic Acid Derivatives
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The three sp2 orbitals of the carbonyl carbon form three σ bonds, one each with the carbonyl oxygen, the α carbon, and the heteroatom, whereas the other two sp2 orbitals of the carbonyl oxygen are occupied by the lone pairs. Further, the unhybridized p...
Carboxylic acid derivatives contain an acyl group attached to a heteroatom such as chlorine, oxygen, or nitrogen. The carbonyl carbon and oxygen are both sp2-hybridized with an unhybridized p orbital.
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01:19Reactions of Acid Anhydrides
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01:19Structure of Amines
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The IUPAC and common names of amides are derived from the parent carboxylic acid, by replacing the suffix “oic acid” and “ic acid,” respectively, with “amide.” In the following example, the IUPAC name ethanamide is derived from ethanoic acid, and the common name, acetamide, is obtained from acetic acid.
01:10Nomenclature of Aryl and Heterocyclic Amines
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