137117-08-9

Upstream product

• 4096-21-3 N-phenylpyrrolidine 
• 93-97-0 benzoic acid anhydride 
• 98-88-4 benzoyl chloride 
• 137116-94-0 1,3-diphenyl-4,5,6,7-tetrahydro-1H-1,2-diazepine 

Relevant academic research and scientific papers

Metal-Free α-C(sp3)-H Aroylation of Amines via a Photoredox Catalytic Radical-Radical Cross-Coupling Process

Here we describe an unprecedented metal-free C(sp3)-H aroylation of amines via visible-light photoredox catalysis, which provides a straightforward route for the construction of a useful α-amino aryl ketone skeleton. Additionally, a number of selected products exhibit good biological activity for protecting PC12 cell damage, which shows that this skeleton has the potential to become a new neuroprotective agent. Finally, a series of mechanism experiments indicate that this transformation undergoes a photoredox catalytic radical-radical cross-coupling pathway.

Direct Acylation of C(sp3)-H Bonds Enabled by Nickel and Photoredox Catalysis

Using nickel and photoredox catalysis, the direct functionalization of C(sp3)-H bonds of N-aryl amines by acyl electrophiles is described. The method affords a diverse range of α-amino ketones at room temperature and is amenable to late-stage coupling of complex and biologically relevant groups. C(sp3)-H activation occurs by photoredox-mediated oxidation to generate α-amino radicals which are intercepted by nickel in catalytic C(sp3)-C coupling. The merger of these two modes of catalysis leverages nickel's unique properties in alkyl cross-coupling while avoiding limitations commonly associated with transition-metal-mediated C(sp3)-H activation, including requirements for chelating directing groups and high reaction temperatures. Teamwork: The direct functionalization of C(sp3)-H bonds of N-aryl amines by acyl electrophiles is achieved, thus affording a diverse range of α-amino ketones at room temperature. C(sp3)-H activation occurs by photoredox-mediated oxidation to generate α-amino radicals which are intercepted by nickel in catalytic C(sp3)-C coupling.

Studies on the Fischer Indole Synthesis: Rearrangements of Five-, Six- and Seven-membered Cyclic Hydrazones of Pyrazoline, Tetrahydropyridazine and Tetrahydro-1,2-diazepine Series in Polyphosphoric Acid

The rearrangements of a few cyclic phenylhydrazones structurally related to 1-phenyl-Δ2-pyrazoline, 1-phenyl-1,4,5,6-tetrahydropyridazine, and 1-phenyl-4,5,6,7-tetrahydro-1,2-diazepine in hot polyphosphoric acid (PPA) are described.The five-membered-ring substrates (the pyrazolines) did not undergo the sigmatropic rearrangement typical of the Fischer indolization, the main reaction course being homolytic N-N bond cleavage, leading to benzidine and its 4-(2-benzoylethyl)-4'-(3-phenyl-Δ2-pyrazolin-1-yl) derivative.The six-membered heterocycles underwent two different reactions, both involving the tautomeric enehydrazine form: the first one is the sigmatropic rearrangement, expected for open-chain hydrazones, affording 4-acyl-1,2,3,4-tetrahydroquinoline derivatives; the second one is a retro-Diels-Alder reaction producing methyleneaniline and α,β-unsaturated carbonyl compounds.The seven-membered-ring substrate gave a 5-acyltetrahydrobenzazepine, resulting from the rearrangement, together with both a pyrrolidine and a pyrazine by-product; their formation involves homolytic N-N bond cleavage of the ring, a δ hydrogen abstraction, followed by intramolecular or intermolecular ring closure.Chemical proofs are given for the new structures.