[reaction: see text] The scope and generality of a new reaction of indoles with MTAD is discussed. In most cases the ene-type reaction proceeds within seconds or minutes at 0 degrees C to provide the urazole adducts in high yield. This reaction provides the first method for protecting the indole 2,3-double bond since the urazole adducts can be reconverted to the starting indole (retro-ene) simp...

A novel synthesis of triazolo[1,2-a]indazole-1,3,8-trione derivatives by reaction of urazole, dimedone and aromatic aldehydes under conventional heating and microwave irradiation and solvent-free conditions using silica nanoparticles prepared from rice husk ash as catalyst is described. The new method features high yields, multicomponent reactions and environmental friendliness.

Axially chiral compounds play an important role in areas such as asymmetric catalysis. The tyrosine click-like reaction is an efficient approach for synthesis of urazoles with potential applications in pharmaceutical and asymmetric catalysis. Here we discover a class of urazole with axial chirality by restricted rotation around an N-Ar bond. By using bifunctional organocatalyst, we successfully...

The functionalization of substrates with radical species has been shown to be a promising strategy confer novel physical and chemical properties surface. Urazole radicals are persistent nitrogen-centered that insensitive oxygen, making them desirable targets for the surfaces. Here, we succeed in preparation self-assembled monolayers (SAMs) 1-arylurazole on Au surfaces using two different approa...

The relative free aldehyde content of eight hexoses and four pentoses has been estimated within about 10% from the rate constants for their reaction with urazole (1,2,4-triazole-3,5-dione). These values of the percent free aldehyde are in agreement with those estimated from CD measurements, but are more accurate. The relative free aldehyde contents for the aldoses were then correlated to variou...

An unprecedented catalytic asymmetric ring-opening of easily accessible 2,3-heterosubstituted norbornenes with hard alkyl metals (R-M), is able to give a practical regioand stereoselective access to hetero-functionalized alkyl cyclopentenes in an enantioenriched form. The copper-catalyzed desymmetrization reaction with trialkylaluminums of sterically hindered and rigid, trior tetracyclic Diels–...

Appropriately substituted N-centered urazolyl radicals are capable of generating interesting cage-like structures upon forming N-N bonds. The generated by the oxidation corresponding NH urazole precursors. We synthesized a triurazole precursor that we hoped would dimerize through formation three bonds to afford large molecular cage. Unfortunately, attempts at urazoles form instead only lead ran...