The application of novel boron complexes in asymmetric transfer hydrogenation of aromatic ketones
[ X ]
Tarih
2015
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Pergamon-Elsevier Science Ltd
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Asymmetric transfer hydrogenation using iso-PrOH as a hydrogen source offers an attractive route for reducing simple unsymmetrical functionalized ketones to chiral alcohols. The combined use of organometallic and coordination chemistry has produced a number of new and powerful synthetic methods for important classes of compounds in general and for optically active substances in particular. For this aim, the (S,Z)-1-((1-hydroxy butane-2-yl imino)methyl)naphthalene-2-ol chiral ligand was chosen to obtain boron complexes. Boronic derivative compounds such as phenylboronic acid, 6-methoxynaphthalen-2-ylboronic acid, 4-methyl-3-nitrophenylboronic acid and 1,4-phenylenediboronic acid were applied to obtain complexation with chiral based ligands. The structures of these ligands and their complexes have been elucidated by a combination of multinuclear NMR spectroscopy, LC MS/MS, TGA/DTA, UV Vis., elemental analysis, XRD, SEM, and FTIR. These boron complexes have also been tested as catalysts in the enantioselective transfer hydrogenation of acetophenone derivatives to afford the corresponding product, (S)-1-phenylethanol with high conversions (up to 99%) and modest enantioselectivities (up to 70% ee). The substituents on the backbone of the ligands had a significant effect on both the activity and % ee. (C) 2015 Elsevier Ltd. All rights reserved.
Açıklama
Anahtar Kelimeler
[No Keyword]
Kaynak
Tetrahedron-Asymmetry
WoS Q Değeri
Q2
Scopus Q Değeri
N/A
Cilt
26
Sayı
18-19
