Chemoselective nitration of aromatic sulfonamides with tert-butyl nitrite

tert-Butyl nitrite mediated nitrogen transfer reactions: synthesis of benzotriazoles and azides at room temperature

A conversion of o-phenylenediamines into benzotriazoles is reported with tert-butyl nitrite at room temperature. The optimized condition is also well suited for the transformation of sulfonyl and acyl hydrazines into corresponding azides.

Regioselective nitration of anilines with Fe(NO3)3·9H2O as a promoter and a nitro source

A novel and efficient ortho-nitration reaction of aniline derivatives using the inexpensive and nontoxic Fe(NO₃)₃·9H₂O as a promoter and a nitro source has been developed.

Regiocontrolled Synthesis of α-Sulfonylmethyl o-Nitrostyrenes via ZnI2-Mediated Sulfonylation and AgNO2/Pd(PPh3)4-Promoted o-Nitration

We report herein the AgNO₂/Pd(PPh₃)₄-promoted regiocontrolled o-nitration of α-sulfonylmethylstyrenes in MeNO₂ with good yields. The o-nitration process provides a series of sulfonyl o-nitrostyrenes. Substituted α-sulfonylmethylstyrenes were synthesized from ZnI₂-mediated sulfonylation of substituted α-methylstyrenes and sodium sulfinates (RSO₂Na) in MeCN with good to excellent yields. The structures of the key products were confirmed by X-ray crystallography. A plausible mechanism has been proposed herein.

tert-Butyl nitrite (TBN) as the N atom source for the synthesis of substituted cinnolines with 2-vinylanilines and a relevant mechanism was studied

A green method to synthesize cinnolines by 6π electrocyclic reaction with alkenyl amines and TBN has been developed.

Co-catalyzed highly selective C(sp3)–H nitration

A Co-catalyzed highly selective C(sp³)–H nitration via a radical pathway was disclosed, overcoming the strong coordination effect of pyrimidine by suppressing C(sp²)–H functionalization as well as proximity C(sp³)–H functionalization.

A FRET-based ratiometric redox probe for detecting oxidative stress by confocal microscopy, FLIM and flow cytometry

Understanding the role of oxidative stress in disease requires real time monitoring of redox status within a cell. We report a FRET-based, ratiometric redox probe which can be applied to monitor cellular oxidative capacity using three different modalities – confocal microscopy, fluorescence lifetime imaging and flow cytometry.

In situ formation of bromobenzene diazonium ions and their spontaneous reaction with carbon-coated LiFePO4 in organic media

In this study, the diazotization of bromoaniline in the presence of carbon-coated LiFePO₄ and the grafting of bromobenzene moieties are investigated.

Mild hypervalent iodine mediated oxidative nitration of N-aryl sulfonamides

An oxidative and acid-free method for the nitration of N-aryl sulfonamides has been developed using a combination of sodium nitrite as cheap and easy to handle NO2-source and the hypervalent iodine reagent PIFA as stoichiometric oxidant. Under very mild reaction conditions, the desired mononitrated aryl sulfonamides were isolated in up to 87% yield. This is the first example of an iodane-mediated oxidative nitration.

Palladium-catalyzed oxidative 6-exo-trig cyclization of 1,6-enynes: facile synthesis of bicyclo[4.1.0]heptan-5-ones

We here describe a new palladium-catalyzed oxidative 6-exo-trig cyclization of 1,6-enynes at room temperature using tBuONO as an oxidant for the synthesis of 3-bicyclo[4.1.0]heptan-5-ones.

Metal-free nitro-carbocyclization of 1,6-enynes with tBuONO and TEMPO

A novel and convenient metal-free nitration and cyclization of 1,6-enynes has been developed.

Metal-free regioselective C-3 nitration of quinoline N-oxides with tert-butyl nitrite

A direct, regioselective and eco-friendly C3-nitration of quinoline N-oxides using tert-butyl nitrite as both the nitro source and oxidant has been developed. This reaction undergoes a free radical process and can be smoothly scaled up to gram scale.

A novel transition metal free [bis-(trifluoroacetoxy)iodo]benzene (PIFA) mediated oxidative ipso nitration of organoboronic acids

A mild, convenient and transition metal free methodology for oxidative ipso nitration of organoboronic acids, including heteroaryl- and alkylboronic acids, has been developed using a combination of [bis-(trifluoroacetoxy)]iodobenzene (PIFA) – N-bromosuccinimide (NBS) and sodium nitrite as the nitro source.

Regioselective synthesis of nitrosoimidazoheterocycles using tert-butyl nitrite

A simple and practical method has been developed for the regioselective nitrosylation of imidazopyridines via C(sp²)–H bond functionalization using tert-butyl nitrite under mild reaction conditions.

Metal-free nitrative cyclization of N-aryl imines with tert-butyl nitrite: dehydrogenative access to 3-nitroindoles

A novel metal-free oxidative C–H functionalization and nitrative cyclization access to 3-nitroindoles from N-aryl imines is described.

Stereoselective intermolecular nitroaminoxylation of terminal aromatic alkynes: trapping alkenyl radicals by TEMPO

The vinyl radical is one of the most unstable organic radicals. It is demonstrated that a nitro radical attacks phenylacetylene and makes the phenyl ring deconjugated with a double bond so that the resulting vinyl radical may be stabilized by delocalization to the phenyl ring's π orbital and easily trapped by TEMPO. It is noteworthy that all desired products were obtained in moderate to good yields in an (E)-configuration.