- Synthesis of imines from nitrobenzene and TiO2 particles suspended in alcohols via semiconductor photocatalysis type B
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UV irradiation on a non-aqueous suspension of titanium dioxide with nitrobenzene and different alcohols in deaerated conditions produces imines and aniline as main products. The conversion of nitrobenzene and the corresponding selectivity of imines or aniline depend on the type of alcohol used. A low conversion (3-12%) and selectivity close to 100% to imines were obtained with methyl, ethyl, or propyl alcohol. Otherwise, using i-propanol only aniline was detected with a conversion of 13%. Finally, a mixture of aniline and imines was formed employing n-butyl, n-amyl, and i-amyl alcohols with the higher conversion (~50%).
- Rios-Bern?, Omar,Flores, Sergio O.,Córdova, Iván,Valenzuela, Miguel A.
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- Synthesis of 3-Formylindoles via Electrochemical Decarboxylation of Glyoxylic Acid with an Amine as a Dual Function Organocatalyst
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A new method for 3-formalytion of indoles has been developed through electrochemical decarboxylation of glyoxylic acid with the amine as a dual function organocatalyst. The amine facilitated both the electrochemical decarboxylation and the nucleophilic reaction efficiently, whose loading can be as low as 1 mol %. This protocol has a broad range of functional group tolerance under ambient conditions. The gram-scale experiment has shown great potential in the synthetic application of this strategy.
- Lin, Dian-Zhao,Huang, Jing-Mei
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- Cyclocondensation of lower aliphatic aldehydes with arylamines and cyclopentadiene
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Three-component condensation of lower aliphatic aldehydes (C 1-C3) with arylamines and cyclopentadiene (the Povarov reaction) gave 3a,4,5,9b-tetrahydro-3H-cyclopenta[c]-quinolines. Ozonization of their N-trifluoroacetyl derivatives a
- Tolstikov,Savchenko,Lukina,Afon'Kina,Nedopekin,Khalilov,Odinokov
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- Photocatalytic reaction of arylamines/alcohols on TiO2 nano-particles
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In this article, the photocatalytic reaction of aniline and 4-amino N,N-dimethyl aniline with methanol, ethanol and isopropanol on anatase TiO 2 nano-particles under UV (365-nm wavelength) irradiation was examined. The concentration of unreacted arylamines and products was measured by gas chromatography picks integration, and then the products were identified by mass spectroscopy analysis. By making a comparison within the rates of photocatalysis of each arylamine in different alcohols under various irradiation times, it was revealed that, in all cases, the sequence of photocatalysis rate was methanol > ethanol > isopropanol. In reactions where the concentrations of arylamine were lower than 10 mmol/l, imines were the main products and the alkylation of amines was not observed. In the higher concentration of arylamines, oxidation and dimerization was occurred. Springer Science+Business Media B.V. 2010.
- Hosseinnia, Azarmidokht,Pazouki, Mohammad,Karimian, Ketauon
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- Carbonylation of nitrobenzene in methanol with palladium bidentate phosphane complexes: An unexpectedly complex network of catalytic reactions, centred around a Pd-imido intermediate
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The reactivity of palladium complexes of bidentate diaryl phosphane ligands (P2) was studied in the reaction of nitrobenzene with CO in methanol. Careful analysis of the reaction mixtures revealed that, besides the frequently reported reduction products of nitrobenzene [methyl phenyl carbamate (MPC), N,N′-diphenylurea (DPU), aniline, azobenzene (Azo) and azoxybenzene (Azoxy)], large quantities of oxidation products of methanol were co-produced (dimethyl carbonate (DMC), dimethyl oxalate (DMO), methyl formate (MF), H 2O, and CO). From these observations, it is concluded that several catalytic processes operate simultaneously, and are coupled via common catalytic intermediates. Starting from a P2Pd0 compound formed in situ, oxidation to a palladium imido compound P2PdII=NPh, can be achieved by de-oxygenation of nitrobenzene 1) with two molecules of CO, 2) with two molecules of CO and the acidic protons of two methanol molecules, or 3) with all four hydrogen atoms of one methanol molecule. Reduction of P 2PdII=NPh to P2Pd0 makes the overall process catalytic, while at the same time forming Azo(xy), MPC, DPU and aniline. It is proposed that the Pd-imido species is the central key intermediate that can link together all reduction products of nitrobenzene and all oxidation products of methanol in one unified mechanistic scheme. The relative occurrence of the various catalytic processes is shown to be dependent on the characteristics of the catalysts, as imposed by the ligand structure.
- Mooibroek, Tiddo J.,Schoon, Lodi,Bouwman, Elisabeth,Drent, Eite
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- Copper(i)-catalysed intramolecular hydroarylation-redox cross-dehydrogenative coupling ofN-propargylanilines with phosphites
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Intramolecular hydroarylation-redox cross-dehydrogenative coupling ofN-propargylanilines with phosphite diesters proceeded in the presence of Cu(i)-catalysts (20 mol%) to selectively give 2-phosphono-1,2,3,4-tetrahydroquinolines in good yields with 100% atomic utilization. P-H and two C-H bonds are activated at once and these hydrogen atoms are trapped by a propargylic triple bond in the molecule.
- Li, Guangzhe,Yu, Guo,Wang, Chengdong,Morita, Taiki,Zhang, Xuhai,Nakamura, Hiroyuki
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supporting information
p. 113 - 116
(2021/12/29)
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- [3+1+1+1] Annulation to the Pyridine Structure in Quinoline Molecules Based on DMSO as a Nonadjacent Dual-Methine Synthon: Simple Synthesis of 3-Arylquinolines from Arylaldehydes, Arylamines, and DMSO
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A [3+1+1+1] annulation of arylamines, arylaldehydes, and dimethyl sulfoxide (DMSO) to the pyridine structure in quinolines using DMSO as a nonadjacent dual-methine (═CH?) synthon is disclosed. In this annulation, arylamines provide two carbon atoms and one nitrogen atom, arylaldehydes furnish one carbon atom, and DMSO provides two nonadjacent methines (═CH?) to the pyridine ring in quinoline molecules. This annulation provides a simple approach for the synthesis of 3-arylquinolines from readily available substrates in useful yields. On the basis of the control experiments and the literature, a plausible mechanism is proposed.
- Guo, Can-Cheng,Li, Hui,Liu, Qiang,Luo, Wei-Ping,Nie, Zhiwen,Su, Miao-Dong,Yang, Tonglin
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- Sulfated polyborate: A dual catalyst for the reductive amination of aldehydes and ketones by NaBH4
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An efficient, quick, and environment-friendly one-pot reductive amination of aldehydes or ketones was developed. In ethanol at 70 °C, a imination catalyzed by sulfated polyborate and further reduced by sodium borohydride yields various amines. The present method has many significant benefits, including a shorter reaction time, excellent yields, and a hassle-free, straightforward experimental process. The reaction has a wide range of applications due to its flexibility, including secondary amine for reductive amination.
- Ganwir, Prerna,Chaturbhuj, Ganesh
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supporting information
(2021/05/19)
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- Iron-Catalyzed Regioselective α-C-H Alkylation of N-Methylanilines: Cross-Dehydrogenative Coupling between Unactivated C(sp3)-H and C(sp3)-H Bonds via a Radical Process
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The iron-catalyzed α-C-H alkylation of N-methylanilines without any directing group by cross-dehydrogenative coupling between unactivated C(sp3)-H and C(sp3)-H bonds has been established for the first time, which provides a good complement to C(sp3)-H activation reactions and expands the field of Fe-catalyzed C-H functionalizations. Many different C(sp3)-H bonds in cyclic alkanes, cyclic ethers, and toluene derivatives can be used as coupling partners. Mechanistic investigations including the radical reaction process, the main role of various reagents, and the kinetic isotope effect experiment were also described.
- Li, Ze-Lin,Sun, Kang-Kang,Wu, Peng-Yu,Cai, Chun
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p. 6830 - 6839
(2019/06/14)
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- Precise regulation of the selectivity of supported nano-Pd catalysts using polysiloxane coatings with tunable surface wettability
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A facile method was developed for surface modification of supported nano-Pd catalysts with tailorable wettability. The obtained Pd/TiO2@POS catalytic materials could be used in the controllable synthesis of styrene and ethylbenzene obtained from hydrogenation of phenylacetylene and the selective synthesis of imine and N-methylanilines via a reductive amination reaction. The precise modification of the hydrophilicity/hydrophobicity of the catalyst surface is crucial to realize this targeted transformation.
- Wang, Hongli,Gao, Ziqian,Wang, Xinzhi,Wei, Ruiping,Zhang, Junping,Shi, Feng
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supporting information
p. 8305 - 8308
(2019/07/16)
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- Expedient stereospecific Co-catalyzed tandem C-N and C-O bond formation of: N -methylanilines with styrene oxides
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Cobalt(ii)-catalyzed stereospecific coupling of N-methylanilines with styrene oxides is developed via tandem C-N and C-O bond formation using tert-butyl hydroperoxide (TBHP) as an oxidant. Optically active epoxide can be reacted with high optical purity.
- Satheesh, Vanaparthi,Vivek Kumar, Sundaravel,Punniyamurthy, Tharmalingam
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supporting information
p. 11813 - 11816
(2018/12/01)
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- Highly Selective N-Monomethylanilines Synthesis from Nitroarene and Formaldehyde via Kinetically Excluding of the Thermodynamically Favorable N,N-Dimethylation Reaction
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The synthesis of N-monomethylamine remains a challenging topic because the N,N-dimethylation reaction is thermodynamically favorable. In this work, the kinetically controlled N-monomethylamine synthesis from nitroarene and paraformaldehyde/H2 is reported to have superhigh N-monomethylamine selectivity in the presence of a Pd/TiO2 catalyst. The superior selectivity should be attributed to the preferential adsorption of the primary amine over N-monomethylamine on the Pd/TiO2 surface, as elucidated by NH3/Me2NH-TPD, while the excellent catalytic activity could be associated with the good H2 activation ability and high amine adsorbing capacity of the catalyst, as elucidated by NH3-TPD and H2-TPR tests. Good results were obtained with a variety of nitroarenes containing methyl, methoxyl, hydroxyl, fluoride, trifluoromethyl, ester, and amide substituents as starting materials, and the potential synthetic utility of this protocol in pharmaceutical is illustrated by N-monomethylation of drug molecules, such as clinidipine, nimesulide, procaine, and methyl aminosalicylate.
- Wang, Hongli,Yuan, Hangkong,Yang, Benqun,Dai, Xingchao,Xu, Shan,Shi, Feng
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p. 3943 - 3949
(2018/05/23)
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- N -Monomethylation of amines using paraformaldehyde and H2
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The selective N-monomethylation of amines is an important topic in fine chemical synthesis. Herein, for the first time, we described a selective N-monomethylation reaction of amines with paraformaldehyde and H2 in the presence of a CuAlOx catalyst. A variety of amines, including primary aromatic amines, benzylamine and cyclohexylamine, as well as secondary amines, have been shown to be compatible with this reaction.
- Wang, Hongli,Huang, Yongji,Dai, Xingchao,Shi, Feng
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supporting information
p. 5542 - 5545
(2017/07/06)
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- Stereospecific copper-catalyzed domino ring opening and sp3 C-H functionalization of activated aziridines with N-alkylanilines
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Copper efficiently catalyzed nucleophilic ring opening, sp3 C-H functionalization, and C-N bond formation in the presence of tert-butyl hydroperoxide to afford functionalized imidazolidines starting from N-sulfonylaziridines and Nalkylanilines. The products were obtained in high optical purities (95 → 99% ee) with excellent functional group tolerance.
- Sengoden, Mani,Bhowmick, Abhisikta,Punniyamurthy, Tharmalingam
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supporting information
p. 158 - 161
(2017/11/27)
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- Method for implementing amine compound N-methylation by photocatalysis
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The invention belongs to the technical field of photocatalysis synthesis, and particularly relates to a method for implementing amine compound N-methylation by photocatalysis. The method includes the steps: 1) adding photocatalyst TiO2 and N-methylation carbon sources into a photocatalysis reactor to form a reaction system, and stirring the reaction system under ultraviolet irradiation; 2) adding reducing agents and amine compounds into the reaction system obtained in the step 1), and continually stirring mixture under ultraviolet irradiation to obtain N-methylation products. Compared with the prior art, the preparation method has the main advantages that selected raw materials are low in cost and toxicity, reaction conditions are mild, energy consumption is less, used catalysts are low in cost and easy to obtain, reaction operations are simple, and products are high in yield and good in selectivity.
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Paragraph 0034; 0035
(2017/09/01)
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- Two consecutive palladium(II)-promoted C-H alkenylation reactions for the synthesis of 3-alkenylquinolones
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Highly substituted quinolones are obtained through an efficient and atom economical procedure that involves two consecutive palladium(II)-catalyzed C-H alkenylation reactions. A selective 6-endo intramolecular C-H alkenylation leads to 4-substituted quinolones that have been further functionalized at C-3 through a second intermolecular C-H alkenylation reaction.
- Ortiz-de-Elguea, Vernica,Sotomayor, Nuria,Lete, Esther
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supporting information
p. 463 - 473
(2015/03/05)
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- Mn(III)-based oxidative cyclization of N-aryl-3-oxobutanamides. facile synthesis and transformation of substituted oxindoles
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The oxidation of 3-oxo-N-phenylbutanamides 1 with manganese(III) acetate in ethanol afforded dimeric 3,3'-biindoline-2,2'-dione derivatives 3-5. A similar reaction of N,2-disubstituted N-aryl-3-oxobutanamides 6 in acetic acid produced 3-acetylindolin-2-ones 7 bearing various substituents in good to excellent yields. The acetylindolinones 7 were easily deacetylated by treatment using neutral alumina in diethyl ether. Both the acetylindolinones 7 and deacetylated indolinones 8 were transformed by reduction into the substituted 1H-indoles.
- Kikue, Nobutaka,Takahashi, Tetsuya,Nishino, Hiroshi
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p. 540 - 562
(2015/03/04)
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- Synthesis of 2-unsubstituted 1-arylimidazoles
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A method has been developed for the synthesis of 1-arylimidazoles lacking a substituent at position 2, featuring the preparation of 1-arylimidazole N-oxides stabilized as boron trifluoride derivatives, with subsequent reduction to the desired imidazoles. This method permits broad variation of the substituents in the aryl part of these molecules.
- Mityanov,Perevalov,Tkach
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p. 1793 - 1800
(2013/07/26)
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- New approaches to photocatalytic reaction of low concentrations of arylamines in alcohols
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Photocatalytic interactions of a series of arylamines, for example 1,4- phenylenediamine, 1,2-phenylenediamine, 4-aminophenol, and 2-aminophenol, at low concentrations in typical primary alcohols have been investigated in the presence of anatase TiO2 nanopowder. GC-MS analysis of the irradiated solutions showed that, except for 1,2-phenylenediamine, 10 mmol/l alcoholic solutions of the arylamines gave predominately the corresponding imines. Irradiation of 2-aminophenol under these conditions, led to oxidation and dimerization to 2-amino-3Hphenoxazin- 3-one. Springer Science+Business Media B.V. 2012.
- Hosseinnia, Azarmidokht,Keyanpour-Rad, Mansoor
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p. 1411 - 1420
(2012/11/07)
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- Method of preparing electron deficient olefins
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This invention relates to a process for producing electron deficient olefins, such as 2-cyanoacrylates, using an iminium salt.
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Page/Page column 7
(2010/06/11)
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- Direct asymmetric aza Diels-Alder reaction catalyzed by chiral 2-pyrrolidinecarboxylic acid ionic liquid
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The utility of [EMIm][Pro] as an efficient catalyst for the one-pot direct asymmetric aza Diels-Alder reaction has been developed. A set of cyclic α,β-unsaturated ketones have been explored in up to 93% yield with up to >99/1 dr and >99% ee. Moreover, the catalytic system can be recycled and reused for six times without any significant loss of catalytic activity.
- Zheng, Xin,Qian, Yunbo,Wang, Yongmei
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experimental part
p. 567 - 570
(2010/08/05)
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- Photocatalytic reaction of aryl amines/alcohols on TiO2 nanoparticles
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In this article, the photocatalytic reaction of aniline and 4-amino N, N dimethyl aniline with methanol, ethanol and isopropanol on anatase TiO 2 nano-particles under UV (365 nm wavelength) irradiation was examined. The concentration of unreacted aryl amines and products was measured by gas chromatography picks integration, and then the products were identified by mass spectroscopy analysis. By making a comparison within the rates of photocatalysis of each aryl amine in different alcohols under various irradiation times, it was revealed that, in all cases, the sequence of photocatalysis rate was methanol > ethanol > isopropanol. In reactions where the concentrations of aryl amine were lower than 10 mmol/L, imines were the main products and alkylation of amines was not observed. In the higher concentration of aryl amines, oxidation and dimerization occurred.
- Hosseinnia, Azarmidokht,Pazouki, Mohammad,Karimian, Ketauon
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experimental part
p. 937 - 945
(2011/12/15)
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- A simple method for the preparation of propargylamines using molecular sieve modified with copper(II)
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A new, heterogeneous, 4 A molecular sieve-supported copper(ii) catalyst was developed and was used successfully in the A3 coupling of alkynes, aldehydes and amines under simple reaction conditions.
- Fodor, Anna,Kiss, Arpad,Debreczeni, Nora,Hell, Zoltan,Gresits, Ivan
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experimental part
p. 4575 - 4581
(2010/11/19)
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- Water-improved heterogeneous transfer hydrogenation using methanol as hydrogen donor over Pd-based catalyst
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The heterogeneous catalytic transfer hydrogenation (CTH) of styrene and nitrobenzene over Pd-based catalyst using methanol as hydrogen donor was investigated in a fixed-bed reactor. With the increase of the molar ratio of water to methanol from 0 to 1, the conversions of styrene and nitrobenzene are increased from 26.3% and 7.1% to 100% and 31.9%, respectively, and the selectivity of aniline is increased from 22.0 to 94.5 mol%. The presence of water improves the hydrogen transfer from methanol to styrene or nitrobenzene through the quick reaction of water with formaldehyde, formed from the dehydrogenation of methanol, into formic acid, which is an excellent hydrogen donor for the CTH of unsaturated organics. In the presence of water, methanol is a better hydrogen donor than isopropanol, n-propanol and ethanol, because water cannot easily react with acetone, propionaldehyde, and acetaldehyde formed from isopropanol, n-propanol, and ethanol, respectively. Additionally, the hydrogen atom utilization of the methanol donor in the presence of water is higher than the other donors, hydrogen atom in a part of water can also be utilized for the reduction of unsaturated organics.
- Xiang, Yizhi,Li, Xiaonian,Lu, Chunshan,Ma, Lei,Zhang, Qunfeng
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scheme or table
p. 289 - 294
(2010/11/18)
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- Method of preparing electron deficient olefins
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This invention relates to processes for producing electron deficient olefins, such as 2-cyanoacrylates, using an iminium salt, and if desired contacting the reaction byproduct with alkali to generate an amine and separating that amine therefrom.
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Page/Page column 10
(2009/08/14)
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- One-pot synthesis of N,N-dimethylaniline from nitrobenzene and methanol
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A route for the direct synthesis of N,N-dimethylaniline from nitrobenzene and methanol was developed through the sequential coupling of the hydrogen production from methanol, hydrogenation of nitrobenzene to produce aniline, and N-methylation of aniline over a pretreated Raney-Ni catalyst (at 443 K in methanol). A high yield of N,N-dimethylaniline up to 98% was obtained by the proposed methodology. In this process, aniline was produced from in-situ hydrogenation of nitrobenzene with hydrogen generated from methanol, or transfer hydrogenation of nitrobenzene with methanol as donor, while methanol acted as a hydrogen source, alkylating reagent and solvent, simultaneously. Additionally, a plausible mechanism of this one-pot reaction process has been described.
- Xu, Long,Li, Xiaonian,Zhu, Yifeng,Xiang, Yizhi
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experimental part
p. 2051 - 2054
(2009/12/25)
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- Synthesis of functionalized carbamates through a palladium-catalyzed reductive carbonylation of substituted nitrobenzenes
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The palladium-catalyzed reductive carbonylation of ortho and para-substituted nitrobenzenes has proven to be an attractive route for the synthesis of functionalized carbamates. For the Pd(1,10-phenanthroline)2(triilate}2 catalyst system, the scope of the reaction has been studied. Substrates with electron-donating substituents at the para position were found to decrease the catalytic activity, most probably as a result of their relatively low oxidizing capacity. The selectivity towards the desired carbamate, however, was increased for these substrates. Under the influence of electron-withdrawing substituents the azoxybenzene and azobenzene derivatives became important side products. Introduction of large steric hindrance at the ortho position of the nitro substrates gave rise to an interesting side reaction, viz. methoxylation of the aromatic ring. The methoxylation reaction appeared to occur on an intermediate species in the catalytic cycle. Several functionalities have shown to be resistant to the reaction conditions required for the conversion of the nitro group. Especially with 4-nitrobenzoic acid, an extremely high activity and selectivity was found, thus yielding a very convenient synthesis for N-protected amines containing carboxylic acid functions. VCH Verlagsgesellschaft mbH.
- Wchman, Petra,Borst, Leo,Kamer, Paul C. J.,Van Leeuwen, Piet W. N. M.
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- Substituted Bicyclic and Tricyclic Oxazolo-1,2,3-Triazole Systems: Ring Expansions to 1,3,4,5-Oxatriazines and Ring Contractions to 1,2,3-Triazaspiroalkane Derivatives
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Synthesis of a range of new bicyclic and tricyclic fused oxazolo-1,2,3-triazole systems is described.Treatment of these with acid caused transformations to substituted 1,3,4,5-oxatriazine and new 1,2,3-triazaspiroalkane systems which were isolated in high yields.Kinetic studies of the ring transformations indicated the presence of a delocalised carbocation intermediate and the mechanism of the ring expansion and contraction is discussed.
- Butler, Richard N.,O'Shea, Donal F.
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p. 2797 - 2800
(2007/10/02)
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- Photochemical Reactions of Primary Aromatic Amines with Chloromethanes in Solution. II. The Products and Mechanisms of Partial Reactions of Aniline in Tetrachloromethane, Chloroform and Dichloromethane
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Major products of photochemical reactions of aniline in tetrachloromethane, chloroform and dichloromethane have been isolated and identified.The mechanisms of partial reactions have been discussed. - Keywords: Photochemical Reactions, Primary Aromatic Amines, Chloromethanes
- Boszczyk, Wojciech,Latowski, Tadeusz
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p. 1589 - 1592
(2007/10/02)
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- Revisitation of Formaldehyde Aniline Condensation. VII. 1,3,5-Triarylhexahydro-sym-triazines and 1,3,5,7-Tetraaryl-1,3,5,7-tetrazocines from Aromatic Amines and Paraformaldehyde
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A product study of the reaction between a number of aromatic amines substituted with widely different groups and paraformaldehyde in inert solvents was performed and found to yield 1,3,5-triaryl-1,3,5-hexahydrotriazines, 1,3,5,7-tetraaryl-1,3,5,7-tetrazocines and formaminals.It was not possible to correlate the product outcomes with the actual structure of the amine substrate.The X-ray diffraction structural determination of 1,3,5-tri-(t-butylphenyl)- (1b) and 1,3,5-tri-(m-fluorophenyl)-1,3,5-hexahydrotriazine (1c) showed the diaxial arrangement of the N-substituents.
- Giumanini, Angelo G.,Verardo, Giancarlo,Zangrando, Ennio,Lassiani, Lucia
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p. 1087 - 1103
(2007/10/02)
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- Cationic Carbon-to-Nitrogen Rearrangements in N-(Arylsulfonoxy)amines
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A series of N-alkyl-O-(arylsulfonyl)hydroxylamines was prepared by the reaction of amines with bis(arylsulfonyl)peroxides.In the absence of base, these amine derivatives underwent rearrangement involving the migration of groups from carbon to nitrogen.The migratory tendencies of the groups which rearranged were found to be in the order Ph>H>alkyl>Me.The migratory aptitudes Ph/Me>72 and n-hexyl/Me=4.2 suggest that these rearrangements are polar in nature and involve electron-deficient nitrogen species.Furthermore the migration of groups was found to be sensitive to the substitution pattern at the migration origin and subject to stereoelectronic control.
- Hoffman, Robert V.,Kumar, Anil
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p. 1859 - 1863
(2007/10/02)
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- Revisitation of Formaldehyde Aniline Condensation. I. High Yield Synthesis of 1,3,5-Triphenylhexahydro-sym-triazine and its X-Ray Crystal Structure Determination
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A rapid and efficient preparation of 1,3,5-triphenylhexahydro-sym-triazine (10) using paraformaldehyde is reported.The trimeric nature of the compound and its structure in solid state, where a biaxial chair conformation is favoured, are conclusively shown by X-ray diffraction analysis.A recent report on a preparation of 1,3-diphenyl-1,3-diazetidine is invalidated.
- Giumanini, Angelo G.,Verardo, Giancarlo,Randaccio, Lucio,Bresciani-Pahor, Nevenka,Traldi, Pietro
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p. 739 - 748
(2007/10/02)
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- Monoalkylation of Primary Aromatic Amines via N-(Alkoxymethyl)aryl Amines. Evidence for the Formation of Stable Monomeric Methyleneamines
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Monomeric methyleneamines (1), formed from N-(alkoxymethyl)arylamines (3), are stable at -60 deg C and may be trapped with organometallic reagents to provide the N-alkylarylamines (7).
- Barluenga, Jose,Bayon, Ana M.,Asensio, Gregorio
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p. 1109 - 1110
(2007/10/02)
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- The Zinc Tetraphenylporphin-sensitized Photoredox Reaction between N-Phenylglycine and p-Benzoquinone in Polar Solvents
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The photoredox reaction between N-phenylglycine (NPG) and p-benzoquinone (BQ) sensitized by zinc tetraphenylporphin (ZnTPP) has been studied in various solvents under nitrogen at 25 deg C.Decarboxylation of NPG and reduction of BQ occurred equimolecularly to give N-methylideneaniline (NMA), carbon dioxide, and hydroquinone (BQH2) when an acetonitrile solution of NPG and BQ was irradiated at λex.>500 nm in the presence of a catalic amount of ZnTPP.ZnTPP was recovered almost quantitatively after the photoreaction.The conversion of NPG increased linearly with increasing the molar ratio of ZnTPP to NPG up to ca. 2E-3.The quantum yield for the ZnTPP-sensitized decarboxylation of NPG(ΦCO2) in nitrogen-purged acetonitrile solution was evaluated as 0.20.The sensitizing activity of ZnTPP was remarkably enhanced upon increasing the solvent polarity.
- Nishimoto, Sei-ichi,Tada, Hiroaki,Kagiya, Tsutomu
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p. 873 - 878
(2007/10/02)
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- The Pyrolysis of N-Allyl Compounds: Free-radical and Retro-ene Mechanisms
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Flash vacuum pyrolysis of N-alkyl-N-allylanilines gives imines by free radical cleavage of the allyl group followed by loss of an atom (or group of atoms) from the α-carbon atom of the alkyl group.The corresponding N-propargyl derivatives also give imines on pyrolysis, but the mechanism is a concerted retro-ene process which may lead to different products from the corresponding N-allyl compound.N-Allyl-N,N-dialkylamines also decompose thermally by a retro-ene process
- Cadogan, J. I. G.,Hickson, Clare L.,McNab, Hamish
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p. 2247 - 2273
(2007/10/02)
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