An Excellent Method for the Mild and Safe Oxidation of N‐Heteroaromatic Compounds and Tertiary Amines

Abstract

Selective, mild and safe N‐oxidation of N‐heteroaromatic compounds and tertiary amines affording high product yields was achieved by using the H2O2‐urea/phthalic anhydride system.

Supramolecular Metallacycles and Their Binding of Fullerenes

“…The synthesis of N ‐oxide ( 3 ) requires standard protection and deprotection procedures for the aldehyde moiety. The oxidation of the pyridine nitrogen can be realized under mild conditions by using urea hydrogen peroxide with phthalic anhydride in acetonitrile . Triaminoguanidinium salts ( 4 ‐X) are obtained by the amination of guanidinium salts with hydrazine hydrate .…”

“…The synthesis of N-oxide (3)r equires standard protection and deprotection procedures for the aldehyde moiety.T he oxidation of the pyridine nitrogen can be realized under mild conditions by using urea hydrogen peroxide with phthalic an-hydridei na cetonitrile. [16] Triaminoguanidiniums alts (4-X) are obtained by the amination of guanidinium salts with hydrazine hydrate. [17] The resulting compounds (5-X) serve as an excellent ligandsf or Zn II .T he reactiono f[ H 3 (pyO) 3 L]Cl with Zn(O 2 CH) 2 in N,N-dimethylformamide resultsi nt he formation of as upramolecularc oordination compound [Zn 24 Cl 24 {(pyO) 3 L} 12 ]( 6,F igure1C) next to ac oordination polymer of unknown composition.…”

Novel Chiral Oxazoline Ligands for Potential Charge-Transfer Effects in the Rh(I)-Catalysed Enantioselective Hydrosilylation

“…Scheme 5 4,4Ј-Bipyridine N,NЈ-dioxide 12 as a single product was obtained in excellent yield (95%) by oxidation of 4,4Ј-bipyridine 4 with excess H 2 O 2 /urea adduct and phthalic anhydride in CH 2 Cl 2 (80% yield were reported by using smaller amounts of oxidising agent [31] ). Condensation of 14 with 2 equivalents of (R)-α-phenylglycinol yielded 15 as the first example of a chiral C 2 -symmetrical 4,4Ј-bipyridine derivative, which is able to coordinate to two metal centres.…”

“…, 1 H, H-6), 9.11 (AAЈBBЈ, 2 H, H-2Ј, H-6Ј). [31] : 80%]) of 4,4Ј-bipyridine N,NЈ-dioxide as the yellow dihydrate, m.p. > 250°C (ref.…”

“…> 250°C (ref. : 305°C [31] , 305Ϫ306°C [36] , 335°C [21] 4,4Ј-Bipyridine-2,2Ј-dicarbonitrile (13): 12 (1.7 g, 7.6 mmol) and dimethyl sulfate (15 ml, 157.7 mmol) were heated at 140°C for 30 min. The cooled solution was treated with ethanol (30 ml) and 70% HClO 4 (10 ml).…”