Different chiral diphosphine ligands were successfully applied to the rhodium catalyzed asymmetric conjugate addition of differently substituted boronic acids to 3-azaarylpropenones containing both pyridinyl and imidazolyl cores. Atropoisomeric (S)-TetraMe-BITIANP (L1) and (S)-BITIANP (L2), together with ligands bearing a mixed chirality as (S,S,Sax)-DIOPHEP (L3), (R,Rax)-ISAPHOS C1 (L4) and (S,Rax,Rax)-ISAPHOS C2 (L5), and the ones containing a stereogenic sp3 carbon ((R,R)-ZEDPHOS L6, (R,R)-EPHOS L8 and their derivatives L7 and L9) have been employed as source of chirality in rhodium complexes. Among this last class of diphosphines, the new phosphorus-based ligand called (R,R)-EPHOS (L8) has been synthesized and employed for the first time as a chiral ligand in rhodium complex for its catalytic activity. Computational studies suggested a cis coordination with a wide bite angle. When applied to the asymmetric conjugate addition of phenyl boronic acid to 3-azaarylpropenone 1, the catalytic system bearing L8 afforded the product 1a in a remarkable 94% e.e. in THF.
New sp3 diphosphine-based rhodium catalysts for the asymmetric conjugate addition of aryl boronic acids to 3-azaarylpropenones / G. Facchetti, M. Fusè, T. Pecoraro, D. Nava, I. Rimoldi. - In: NEW JOURNAL OF CHEMISTRY. - ISSN 1144-0546. - (2021), pp. 1-7. [Epub ahead of print] [10.1039/D1NJ03634C]
New sp3 diphosphine-based rhodium catalysts for the asymmetric conjugate addition of aryl boronic acids to 3-azaarylpropenones
G. Facchetti
Primo
;D. NavaPenultimo
;I. RimoldiUltimo
2021
Abstract
Different chiral diphosphine ligands were successfully applied to the rhodium catalyzed asymmetric conjugate addition of differently substituted boronic acids to 3-azaarylpropenones containing both pyridinyl and imidazolyl cores. Atropoisomeric (S)-TetraMe-BITIANP (L1) and (S)-BITIANP (L2), together with ligands bearing a mixed chirality as (S,S,Sax)-DIOPHEP (L3), (R,Rax)-ISAPHOS C1 (L4) and (S,Rax,Rax)-ISAPHOS C2 (L5), and the ones containing a stereogenic sp3 carbon ((R,R)-ZEDPHOS L6, (R,R)-EPHOS L8 and their derivatives L7 and L9) have been employed as source of chirality in rhodium complexes. Among this last class of diphosphines, the new phosphorus-based ligand called (R,R)-EPHOS (L8) has been synthesized and employed for the first time as a chiral ligand in rhodium complex for its catalytic activity. Computational studies suggested a cis coordination with a wide bite angle. When applied to the asymmetric conjugate addition of phenyl boronic acid to 3-azaarylpropenone 1, the catalytic system bearing L8 afforded the product 1a in a remarkable 94% e.e. in THF.File | Dimensione | Formato | |
---|---|---|---|
Article_submitted.pdf
accesso aperto
Tipologia:
Pre-print (manoscritto inviato all'editore)
Dimensione
717.41 kB
Formato
Adobe PDF
|
717.41 kB | Adobe PDF | Visualizza/Apri |
d1nj03634c.pdf
accesso riservato
Tipologia:
Publisher's version/PDF
Dimensione
2.16 MB
Formato
Adobe PDF
|
2.16 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
Pubblicazioni consigliate
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.