Palladium-catalyzed C(sp)–H arylation of lactic acid: efficient synthesis of chiral β-aryl-α-hydroxy acids†
نویسندگان
چکیده
A Pd-catalyzed arylation of lactic acid employing 8-aminoquinoline as the directing group has been reported. The protocol is found to be compatible with a broad range of synthetically useful functional groups, thus providing a practical route to chiral β-aryl-α-hydroxy acids. Further, the new reaction has also been applied to the synthesis of pharmaceutically important α-hydroxy acids, such as LY519818 and tesaglitazar.
منابع مشابه
Synthesis of chiral α-hydroxy acids via palladium-catalyzed C(sp(3))-H alkylation of lactic acid.
Herein we report a Pd-catalyzed alkylation of lactic acid with the assistance of 8-aminoquinoline auxiliary. A wide range of alkyl iodides bearing β-hydrogen atoms are compatible with the reaction conditions, providing a practical and straightforward alternative to access chiral α-hydroxy acids (AHAs). The new reactions have been applied for the synthesis of isotope-labeled AHAs and a sugar-con...
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Significance: A novel general β-arylation of protected alanine esters to yield synthetically useful (hetero)aryl alanine building blocks has been disclosed. The protocol utilizes a lithium amide to form an enolate that undergoes a palladium-catalyzed C–C coupling with various aromatic bromides. Comment: Interestingly, the reaction could be extended to α-amino acids bearing other linear alkyl ch...
متن کاملSynthesis of chiral a-hydroxy acids via palladium- catalyzed C(sp)–H alkylation of lactic acid†
Herein we report a Pd-catalyzed alkylation of lactic acid with the assistance of 8-aminoquinoline auxiliary. A wide range of alkyl iodides bearing b-hydrogen atoms are compatible with the reaction conditions, providing a practical and straightforward alternative to access chiral a-hydroxy acids (AHAs). The new reactions have been applied for the synthesis of isotope-labeled AHAs and a sugarcont...
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