Iron(III) Chloride Catalyzed Oxidative Coupling of Aromatic Nuclei

Abstract

Easily available and nontoxic FeCl(3) catalyzes intramolecular oxidative coupling for the direct construction of the phenanthrene ring using meta-chloroperbenzoic acid as sole oxidant at room temperature in excellent yields. The mechanistic investigations show that FeCl(3)-catalyzed coupling proceeds through the heterolytic coupling (A(+) + B). The catalytic approach has been applied to intermolecular biaryl coupling of 2-naphthols and phenol ether.

Configuration of stilbene derivatives by 1H NMR and theoretical calculation of chemical shifts

“…Calculated chemical shifts for H 3 and H 10 differ, in opposite directions, by about 1.0 ppm between E and Z-isomers. Although we have experimental values for only one of the isomers, a similar case reported in the literature [24] suggests that a difference in chemical shifts of this magnitude could be expected.…”

Synthesis, complexation behavior and application of a new diphosphite ligand in rhodium-catalyzed hydroformylation

“…In the literature several heterogeneous oxidants such as (tert-BuO) 2 [11], FeCl 3 /H 2 O/O 2 [12], H 2 O 2 /Cucomplexes [13], Fe-salts [14], FeSO 4 /Na 2 S 2 O 8 [15] or K 2 S 2 O 8 [16] are recommended. As oxidants for the homogeneous phenol coupling Fe-or Cu-salts/O 2 , m-chloroperbenzoic acid/FeCl 3 [17] Highest yield was achieved by employment of a modified procedure of Wang and co-workers [17] using benzoyl peroxide as oxidants (Run 2) or m-chloroperbenzoic acid (¼MCPBA)/FeCl 3 (Run 3), which hitherto was used only for the para-coupling of phenols. MCPBA alone did not work.…”

Bireticulol, a bioactive isocoumarin dimer from Streptomyces sp. BCC24731

“…for 3 h to elute out all substances. The crude acetone extract was dried in vacuo to yield a dark brown substance (10.9 g), which was partitioned by Diaion HP20SS (Supelco, Bellefonte, PA, USA) column chromatography (3.5Â25 cm, acetone:water) to yield nine fractions (20,30,40, 50, 60, 70, 80, 90 and 100% acetone mixtures).…”