Synthesis of 3-Borylated Pyrrolidines by 1,3-Dipolar Cycloaddition of Alkenyl Boronates and Azomethine Ylide.
Chemistry
; 28(54): e202202117, 2022 Sep 27.
Article
en En
| MEDLINE
| ID: mdl-35938353
ABSTRACT
A scalable and efficient process for the preparation of 3-borylated pyrrolidines by 1,3-dipolar cycloaddition of N-benzyl azomethine ylide generated inâ
situ has been developed. The optimized method included the use of LiF in DMSO at 110 °C and was suitable for α-mono-, α,ß-di-, and α,ß,ß-trialkyl-, ß,ß-(hetera)cycloalkylidene-, CO2 Et-, as well as most ß-(het)aryl-substituted alkenyl boropinacolates. The 1,3-dipolar reaction proceeded on a multigram scale providing 3-borylated pyrrolidines with diverse substitution patterns (including fused and spirocyclic ones) in a diastereoselective manner. The Pd(OH)2 -mediated N-debenzylation of pyrrolidine hydrochlorides was successfully performed to give the corresponding bifunctional building blocks on an up to 130â
g scale, thus providing a substantial expansion of the synthetic and medicinal chemist's toolbox. Other reactions included the preparation of trifluoroborates, Zweifel-Aggarwal sp3 -sp2 coupling, and oxidative deborylation as an example of C-heteroatom bond formation.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Dióxido de Carbono
/
Dimetilsulfóxido
Idioma:
En
Revista:
Chemistry
Asunto de la revista:
QUIMICA
Año:
2022
Tipo del documento:
Article
País de afiliación:
Ucrania
Pais de publicación:
ALEMANHA
/
ALEMANIA
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DE
/
DEUSTCHLAND
/
GERMANY