7025-95-8Relevant academic research and scientific papers
PHOTODIMERIZATION OF THIOCHROMONE IN AROMATIC SOLVENTS
Still, Ian W. J.,Leong, Toong Sang
, p. 1183 - 1186 (1981)
Photolysis of thiochromone 1a in several aromatic solvents of widely differing ionization potentials leads to the formation of mixtures of all four possible cyclobutane photodimers.In sharp contrast to the photochemical behavior of the analogous sulfone, no evidence for , or for substitutive, photoaddition reactions was found.
High power organic cathodes using thin films of electropolymerized benzidine polymers
Truong, Thanh-Tam,Coates, Geoffrey W.,Abru?a, Héctor D.
supporting information, p. 14674 - 14677 (2015/09/28)
Thin films of benzidine polymers were electrochemically deposited directly onto conductive substrates by oxidative coupling of di- and trianilinoalkane monomers. The electropolymerization and electrochemical properties of the polymers were optimized by varying the alkyl linker. Polymer films exhibited two reversible one-electron transfers at high potentials (>3.3 V vs. Li/Li+) and maintained discharge capacities in excess of 150 mA h g-1 even when discharged in under 4 seconds.
A general catalytic methylation of amines using carbon dioxide
Li, Yuehui,Fang, Xianjie,Junge, Kathrin,Beller, Matthias
supporting information, p. 9568 - 9571 (2013/09/23)
Putting CO2 to work: Carbon dioxide is shown to be a general and selective methylating reagent for secondary and primary, aromatic and aliphatic amines under reductive conditions. A variety of tertiary amines are obtained from CO2 and commercially available silanes in high yields with good tolerance to nitrile, olefin, ether, ester, and hydroxy groups. Copyright
Dynamics of anilinium radical α-heterolytic fragmentation processes. Electrofugal group, substituent, and medium effects on desilylation, decarboxylation, and retro-aldol cleavage pathways
Su, Zhuoyi,Mariano, Patrick S.,Falvey, Daniel E.,Yoon, Ung Chan,Oh, Sun Wha
, p. 10676 - 10686 (2007/10/03)
A single electron transfer (SET) photosensitization technique in conjunction with time-resolved, laser spectroscopy has been employed to generate and kinetically analyze decay processes of anilinium radicals derived by one-electron oxidation of α-anilinocarboxylates, β- anilinoalcohols, and α-anilinosilanes. In this manner, the rates of unimolecular decarboxylation of aniliniumcarboxylate radicals were determined to be in the range 106 - 107 s-1 and dependent upon solvent polarity, the nature of the metal cation, and substituents on the aniline ring, nitrogen, and α-carbon. In addition, kinetic analysis of base-induced retro-aldol fragmentations of cation radicals arising by SET oxidation of β- anilinoalcohols has shown that they occur with bimolecular rate constants which vary from 104 to 105 M-1 s1. These values are close to those for α-deprotonation reactions of related N,N-dialkylanilinium radicals. The retro-aldol fragmentation rates, like those for α-decarboxylation, also vary in a patterned way with changes in arene ring, nitrogen, and α- and β- carbon substituents. An investigation of the dynamics of methanol-promoted reactions of α-(trimethylsilyl)methyl-substituted anilinium radicals, has demonstrated that a change in the nitrogen substituent from alkyl to acyl causes an ca. 10-fold increase in the desilylation rate. Parallel photochemical studies have been conducted to gain chemical evidence to support assignment of the anilinium radical decay pathways in the LFP experiments and to demonstrate the preparative consequences of the kinetic results. First, clean formation of products derived by coupling of the (N- methylanilino)methyl radical in photochemical reactions of 1,4- dicyanobenzene with either tetra-n-butylammonium N-methyl-N-phenylglycinate or β-(N-methyl-N-phenyl)aminoethanol shows that the respective decarboxylation and retro-aldol cleavage processes occur with exceptionally high efficiencies. Second, in accord with the high rates observed for aminium radical decarboxylation and base-induced retro-aldol fragmentation, tethered cyclohexenone - α-aminocarboxylates and - β-aminoethanols undergo high- yielding SET-promoted photocyclization reactions under both direct and SET- sensitized conditions. Last, results which depict how the rates of aminium radical α-fragmentation correlate with quantum efficiencies of SET-promoted reactions of tertiary amines and amides have come from a study of photocyclization reactions of N-(aminoethyl)- and (amidoethyl)phthalimides. The quantum yields for these SET-promoted processes are observed to vary with the electrofugal group and nitrogen substituent in the manner predicted on the basis of the LFP-determined fragmentation rates.
A convenient one-pot synthesis of symmetric secondary and tertiary vicinal diamines
Nutaitis
, p. 1081 - 1085 (2007/10/02)
A convenient one-pot synthesis of symmetric vicinal diamines utilizing sodium borohydride/trifluoroacetic acid reduction methodology is described.
Photoreduction of Triplet Thioxanthone by Amines: Charge Transfer Generates Radicals That Initiate Polymerization of Olefins
Yates, Stephen F.,Schuster, Gary B.
, p. 3349 - 3356 (2007/10/02)
Thioxanthone triplet is photoreduced by amines via a charge-transfer or exciplex intermediate to thioxanthyl ketyl radical.This ion pair can be observed by nanosecond laser spectroscopy in polar solvents with easily oxidized dimethylaniline as reductant.The intermediacy of this species in benzene was indicated by the correlation of triplet quenching rates with amine ionization potential and by the absence of a significant isotope effect in triplet quenching by tert-butylamine-d2.In contrast, tri-n-butylstannane reacts more rapidly than its ionization potential would dictate and exhibits a larger isotope effect.Addition of methyl methacrylate does not significantly alter the rates of decay for the ion pair of ketyl radikal.Product studies show that the aminomethyl radical PhN(CH3)CH2* is the principal initiator of olefin polymerization.
