97971-80-7

Upstream product

• 879-18-5 naphthalene-1-carbonic acid chloride 
• 123-30-8 4-amino-phenol 
• 87503-49-9 N-(1-naphthoyl)-O-(p-toluoyl)-N-phenylhydroxylamine 
• 874-60-2 4-methyl-benzoyl chloride 
• 223272-49-9 N-(4-hydroxy-phenyl)-1-naphthamide 

Relevant academic research and scientific papers

Mechanism of the Direct and Triplet-sensitized Photolysis of N-(1-Naphthoyl)-O-(p-toluoyl)-N-phenylhydroxylamine

Quantum yields (Φ) were determined for benzophenone-sensitized and direct photolysis of the title hydroxylamine (NT).Analysis of linear Stern-Volmer plots of the reciprocal of Φ against the reciprocal of NT concentration reveals that the sensitized decomposition of NT takes place via its first triplet excited state (T1) produced by triplet-triplet energy transfer from benzophenone to NT.The fact that the quantum yields for the direct photolysis are independent of NT concentration indicates no occurence of both self-quenching and induced decomposition of NT by the photochemically generated radicals.Closer examination of the micellar and solvent viscostity effects on the quantum yields for the direct photolysis with 313-nm light shows the existence of at least two spin-correlated (singlet) radical pairs: One is a contact radical pair whose recombination eventually yields 1,3-toluoyloxyl-migrated product and the other a solvent-separated radical pair from which 1,5-toluoyloxyl-migrated product is derived in competition with diffusive escape from the solvent or micelle cage.Exclusive occurence of the direct photolysis from the first singlet excited state (S1) was explained on the basis of the large energy gap between S1 and T1 (31 kcal mol-1) which is likely to make intersystem crossing from S1 to T1 very inefficient.

Mechanism of the Pyrene-Sensitized Photolysis of N-(1-Naphthoyl)-O-(p-toluoyl)-N-phenylhydroxylamine

The title hydroxylamine (NT) undergoes pyrene-sensitized photodecomposition to give rearrangement and fragmentation products.An analysis of linear Stern-Volmer plots, both for the sensitized photolysis of NT and for the fluorescence quenching of pyrene by NT, indicates the involvement of singlet pyrene in this photolysis.The observation of negligible effects of 1,3-cyclohexadiene and trans-stilbene as a triplet quencher on the reaction provides further supporting evidence for a singlet-pathway mechanism.A comparison of the relative state energies of NT and the sensitizer suggests the existence of a reactive singlet-exciplex intermediate formed between the singlet-state sensitizer and the ground-state NT.The results of solvent and micellar effects on the sensitized photolysis establish that electron transfer in the exciplex predominates in a polar solvent, and that in a nonpolar solvent energy transfer in this exciplex plays a major role in the reaction.

The Photolysis of N,O-Diacyl-N-phenylhydroxylamines

The photochemical decomposition of the title compounds yielded the rearrangement products derived from 1,3- and 1,5-aroyloxyl migrations in addition to the fragmentation products typical of the aroyloxyl and amido radicals, while only 1,3-aroyloxyl migration was observed on thermolysis.The results of crossover experiments indicate an intramolecular rearrangement, probably involving homolysis of the N-O bond in the excited states.Triplet quenching studies demonstrate that the rearrangement and fragmentation proceed exclusively via the first excited singlet state.No formation of the rearrangement products on triplet sensitization was expl ained on the basis of the spin multiplicity effects on a radical-radical recombination process within a solvent cage.

HTE PHOTOLYSIS OF N,O-DIACYL-N-PHENYLHYDROXYLAMINES

The photodecomposition of the title compounds yielded the rearrangement products derived from 1,3- and 1,5-aroyloxy migrations in addition to the fragmentation products typical of the aroyloxyl and amido free radicals.Crossover experiments indicate an int