Highly selective oxidative cross-coupling of 2-naphthol derivatives with chiral copper(I)-bisoxazoline catalysts
The asymmetric oxidative coupling reaction of 3-hydroxy-2-naphthoate and 2-naphthol derivatives with the CuCl-(S)-(-)-2,2′-isopropylidenebis(4- phenyl-2-oxazoline) catalyst under an O2 atmosphere was carried out. The reaction proceeded in a highly cross-coupling selective manner (≤99.7%) with a moderate enantioselectivity of up to 65%.
Temma, Tomohisa,Habaue, Shigeki
p. 5655 - 5657
(2007/10/03)
The oxidative cross-coupling of substituted 2-naphthols. Part I: The scope and limitations
Highly selective oxidative cross-coupling of differently substituted 2-naphthols mediated by Cu(II)-tert-butyl amine complexes is described. The 'cross'-products are obtained in good to excellent yields and the selectivity up to >90% is observed depending on the substitution of naphthol nuclei. The alternative procedures - the cross-coupling of free naphthols with CuCl(OMe) as well as the coupling of sodium naphtholates with anhydrous copper(II) chloride - were also studied. All these methods enable a simple and high-yield access to the unsymmetrically substituted binaphthols. A successful optical resolution of methyl 2,2'-dihydroxy-1,1'-binaphthalene-3-carboxylate by means of liquid chromatography on triacetylcellulose and the subsequent configurational correlation with a binaphthol derivative of known absolute configuration is reported.
Hovorka,Scigel,Gunterova,Tichy,Zavada
p. 9503 - 9516
(2007/10/02)
HIGHLY SELECTIVE OXIDATIVE CROSS-COUPLING OF SUBSTITUTED 2-NAPHTHOLS: A CONVIENT APPROACH TO UNSYMMETRICAL 1,1'-BINAPHTHALENE-2,2'-DIOLS
Oxidative cross-coupling of several differently substituted 2-naphthols mediated by Cu(II)-amine complexes is described.The influence of substituents was examined and possible mechanism explaining the observed selectivity has been proposed.
Hovorka, Martin,Guenterova, Jana,Zavada, Jiri
p. 413 - 416
(2007/10/02)
More Articles about upstream products of 128702-28-3