- Mechanism of dye bleaching upon laser excitation of crystal violet bound to bovine serum albumin
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The laser induced photobleaching of crystal violet non-covalently bound to bovine serum albumin yields leuco crystal violet and Michler's ketone as reaction products. The first step of the bleaching process is postulated to be an electron or hydrogen atom transfer from the protein to the dye moiety.
- Indig, Guilherme L.
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- Spectrofluorimetric Hydrodynamic Voltammetry: The Investigation of Electrode Reaction Mechanisms
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Spectrofluorimetric hydrodynamic voltammetry (SFV) is used to study the electroreduction of crystal violet in acetonitrile solution.The SFV technique is shown to have high sensitivity and to complement conventional electrochemical experiments through its identification of leucocrystal violet as an electrolysis product generated in low concentration in addition to the radical species formed as a one-electron adduct of the parent compound and previously thought to be produced exclusively.Mechanistic SFV studies show that the leucocrystal violet is formed via an EC process for which kinetic parameters are reported.
- Compton, Richard G.,Wllington, R. Geoffrey
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- PHOTOREDUCTION OF CRYSTAL VIOLET IN ISOPROPYL ALCOHOL. MECHANISMS INVOLVING A LEUCO ETHER DERIVATIVE AND DYE ION PAIRS
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The photoreduction of crystal violet (CV+) has been studied as a function of excitation wavelenght and the nature of halide counterions in 90 percent isopropyl alcohol (IPA).The dye photobleaches upon excitation in the UV (283 nm) (but not in the visible) and on the selection of chloride and bromide (but not iodide) counterions.Leuco dye (CVH), acetone, and hydrogen ion are the products of photolysis.The presence of a leuco ether (CVOR) in equilibrium with CV+ in alcohol solution was confirmed by equilibration studies.The leuco ether and CV+ (with excess halide) werre subjected to laser flash photolysis (283-nm excitatiom).The transient radical, CV., was observed, consistent with homolytic cleavage of the leuco ether or with photoinduced electron transfer within a CV+X- ion pair involving an upper excited singlet state of CV+.The ion pair of CV+I- gave rise to a new absorption band on addition band of excess iodide; an ion-pair formation constant could be calculated (Kip= 30 M-1).Photoinduced (reversible) electron transfer for CV+I- was observed by flash photolysis (355-nm excitation), and the decay rates for recombination of CV. and I2.- radicals were obtained.Mechanisms of dye photoreduction-alcohol oxidation are propsed to involve hydrogen abstraction from solvent by halogen atoms (photogenerated from ion pairs) or indirectly via homolytic ether cleavage.The pathways of homolytic vs. heterolytic cleavage of CVOR in IPA were inspected by using the laser flash technique.Relevance of the mechanisms of leuco ether cleavage and ion-pair eklectron transfer to the general problem of dye photodegradation is emphasized.
- Jones, Guilford,Goswami, Kisholoy
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- Synthesis of symmetric triarylmethane derivatives catalyzed by AIL ionic liquid
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Abstract: An efficient, eco-friendly ionic liquid was described for the synthesis of symmetric triarylmethane derivatives via Baeyer condensation of N,N-dimethylaniline with different active aromatic aldehyde compounds using amide ionic liquid as a catalyst. The syntheses were achieved for the first time using amide ionic liquid as a catalyst eliminating the need for a volatile organic solvent. The advantages of this ionic liquid are low cost and operational simplicity.
- Kang, Li Q.,Gao, Han,Cai, Yue Q.
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- Organic ligands incorporated hypercrosslinked microporous organic nanotube frameworks for accelerating mass transfer in efficient heterogeneous catalysis
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Microporous organic polymers (MOP) usually have dominated micropores smaller than 2?nm, which may restrict their performance in the mass transfer processes. Adding mesopores into microporous materials to form hierarchical structure has been recognized as a promising route to eliminate their transport limitations and further improve their value in applications. Here we report a straightforward method for the synthesis of organic ligands incorporated hypercrosslinked microporous organic nanotube frameworks (O-HMONFs) via Friedel-Crafts hyper-crosslinking reaction of small aromatic organic ligands with core-shell bottlebrush copolymers as platforms for heterogeneous catalysts. In particular, because of the mesopores produced by the core degradation, O-HMONFs-based catalysts showed more comparable activities than the corresponding disordered MOP-based catalyst and homogeneous molecular catalyst under similar conditions. More importantly, this method might be suitable for various aromatic organic ligands and could be used as a general approach to produce a variety of functional microporous organic nanotube frameworks.
- Xu, Yang,Wang, Tianqi,He, Zidong,Zhou, Minghong,Yu, Wei,Shi, Buying,Huang, Kun
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p. 112 - 119
(2017/05/18)
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- Redox inactive metal ion triggered N-dealkylation by an iron catalyst with dioxygen activation: A lesson from lipoxygenases
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Utilization of dioxygen as the terminal oxidant at ambient temperature is always a challenge in redox chemistry, because it is hard to oxidize a stable redox metal ion like iron(iii) to its high oxidation state to initialize the catalytic cycle. Inspired by the dioxygenation and co-oxidase activity of lipoxygenases, herein, we introduce an alternative protocol to activate the sluggish iron(iii) species with non-redox metal ions, which can promote its oxidizing power to facilitate substrate oxidation with dioxygen, thus initializing the catalytic cycle. In oxidations of N,N-dimethylaniline and its analogues, adding Zn(OTf)2 to the [Fe(TPA)Cl2]Cl catalyst can trigger the amine oxidation with dioxygen, whereas [Fe(TPA)Cl2]Cl alone is very sluggish. In stoichiometric oxidations, it has also been confirmed that the presence of Zn(OTf)2 can apparently improve the electron transfer capability of the [Fe(TPA)Cl2]Cl complex. Experiments using different types of substrates as trapping reagents disclosed that the iron(iv) species does not occur in the catalytic cycle, suggesting that oxidation of amines is initialized by electron transfer rather than hydrogen abstraction. Combined experiments from UV-Vis, high resolution mass spectrometry, electrochemistry, EPR and oxidation kinetics support that the improved electron transfer ability of iron(iii) species originates from its interaction with added Lewis acids like Zn2+ through a plausible chloride or OTf- bridge, which has promoted the redox potential of iron(iii) species. The amine oxidation mechanism was also discussed based on the available data, which resembles the co-oxidase activity of lipoxygenases in oxidative dealkylation of xenobiotic metabolisms where an external electron donor is not essential for dioxygen activation.
- Zhang, Jisheng,Wang, Yujuan,Luo, Nengchao,Chen, Zhuqi,Wu, Kangbing,Yin, Guochuan
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p. 9847 - 9859
(2015/06/08)
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- Solvent-free synthesis of 4,4-diaminotriarylmethanes-leuco malachite materials in the presence of FePO4
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A fast, efficient and versatile route for the synthesis of 4,4-diaminotriarylmethanes is reported using N,N-dimethyl aniline and aryl aldehydes in presence of FePO4 under solvent-free condition at 100°C.
- Behbahani, Farahnaz K.,Khademloo, Elham
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p. 1507 - 1510
(2015/02/05)
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- Towards a comprehensive hydride donor ability scale
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Rates of hydride transfer from several hydride donors to benzhydrylium ions have been measured at 20 °C and used for the determination of empirical nucleophilicity parameters N and sN according to the linear free energy relationship log k20 °C=sN(N+E). Comparison of the rate constants of hydride abstraction by tritylium ions with those calculated from the reactivity parameters sN, N, and E showed fair agreement. Therefore, it was possible to convert the large number of literature data on hydride abstraction by tritylium ions into N and sN parameters for the corresponding hydride donors, and construct a reactivity scale for hydride donors covering more than 20 orders of magnitude.
- Horn, Markus,Schappele, Ludwig H.,Lang-Wittkowski, Gabriele,Mayr, Herbert,Ofial, Armin R.
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supporting information
p. 249 - 263
(2013/02/25)
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- Halogen-free room-temperature bronsted acidic ionic liquid [Hmim]+ HSO4- as a recyclable green "dual reagent" catalysis for the synthesis of triarylmethanes (TRAM s) ;
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The halogen-free Brnsted acidic ionic liquid methylimidazolium hydrogen sulfate ([Hmim]+ HSO4-) acts as a very efficient catalyst for the one-pot, two-component Baeyer condensation of a variety of aromatic aldehydes with dimethyl or diethyl aniline at room temperature. This green reagent behaves as both catalyst and solvent; that is, it exhibits dual-reagent catalysis. The room-temperature acidic ionic liquid could be recycled several times with almost no loss in the yield of the reaction. This is the first report of the Baeyer synthesis with a halogen-free ionic liquid.
- Mukhopadhyay, Chhanda,Datta, Arup,Tapaswi, Pradip Kumar
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experimental part
p. 2453 - 2463
(2012/06/29)
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- SbCl3-catalyzed one-pot synthesis of 4,4′-diamino- triarylmethanes under solvent-free conditions: Synthesis, characterization, and DFT studies
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A simple, efficient, and mild procedure for a solvent-free one-step synthesis of various 4,4′-diaminotriarylmethane derivatives in the presence of antimony trichloride as catalyst is described. Triarylmethane derivatives were prepared in good to excellent yields and characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopic techniques. The structural and vibrational analysis were investigated by performing theoretical calculations at the HF and DFT levels of theory by standard 6-31Gs *, 6-31G*/B3LYP, and B3LYP/cc-pVDZ methods and good agreement was obtained between experimental and theoretical results.
- Bardajee, Ghasem Rezanejade
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experimental part
p. 135 - 144
(2011/05/16)
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- ZrOCl2 catalyzed Baeyer condensation: A facile and efficient synthesis of triarylmethanes under solvent-free conditions
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A facile and efficient synthesis of an array of triarylmethanes by the Baeyer condensation of different arylaldehydes carrying activated and deactivated groups and N,N-dimethyIaniline using a catalytic amount of ZrOCI2 under solvent-free microwave irradiation conditions is described. Further, the catalytic activity of ZrOCI2 is compared with traditional Lewis acid catalysts and found that this synthetic method has the advantages of excellent yields (70-96%), shorter reaction time (few minutes) and solvent-free conditions.
- Reddy, Ch Sanjeeva,Nagaraj,Srinivas,Reddy
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experimental part
p. 248 - 254
(2009/12/03)
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- Doping of an organic molecular semiconductor by substitutional cocrystallization with a molecular n-dopant
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Dopants for organic molecular semiconductors that yield immobile dopant ions are necessary for the creation of stable molecular semiconductor p-n junctions, the basis for almost all traditional inorganic semiconductor devices. We present evidence for the substitutional cocrystallization of tris(4-nitrophenyl)methyl radical (1) with small amounts of tris[4- (dimethylamino)phenyl]methyl radical (2), resulting in n-doped 1 with immobile 2+ counterions. Cyclic voltammetry indicates that electron transfer from 2 to 1 is favored by 0.51 eV. The powder X-ray diffraction patterns of pure 1 and 1 doped with 2 are very similar, indicating substitutional cocrystallization. The electrical conductivity of doped 1 increases with increasing concentration of 2, and the conductivity is constant over time. Variable-temperature conductivity measurements of 1 doped with 2% and 5% 2 indicate that the activation energy of conduction is 0.32 eV at both dopant concentrations. The Royal Society of Chemistry 2007.
- Porter Jr., William W.,Vaid, Thomas P.
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p. 469 - 475
(2008/02/03)
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- Novel reaction of dimethylaniline with tetrabromomethane producing 4,4′-methylenebis(N,N-dimethylaniline)
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Reaction of N,N-dimethylaniline (1) with tetrahalomethanes such as tetrabromomethane and tetrachloromethane in acetonitrile was found to give 4,4′-methylenebis(N,N-dimethylaniline) (2) in considerable yield. The reaction is considered to be initiated by t
- Matsubara, Yoshio,Matsuda, Takuya,Kato, Atsuhisa,Kakedai, Yoshikatsu,Yamaguchi, Yoshihiro
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p. 1885 - 1889
(2007/10/03)
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- Baeyer condensation in chloroaluminate ionic liquid
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1-n-butylpyridinium chloroaluminate serves the dual purpose of a reaction medium and a Lewis acid catalyst for condensation of substituted benzaldehydes with N, N-dimethylaniline to obtain triarylmethanes (leuco bases) in good yields with significant reduction in reaction time and simplification of the workup process.
- Paul, Aniruddha M.,Khandekar, Amit C.,Khadilkar, Bhushan M.
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p. 168 - 169
(2007/10/03)
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- Unexpected products from the formylation of N,N-dimethylanilines with 2-formamidopyridine in POCl3
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The formation of unexpected products from the formylation of N,N-dimethylanilines with 2-formamidopyridine in POCl3 was discussed. The reaction led to the formation of a product derived from two units of the t-aniline and one of the pyridine with less four protons. The formation of these products was due to the oxidation of one of the methyl groups of an N,N-dimethyl-aniline moiety, a process which is initiated by a 't-amino effect' interaction.
- Cheng, Ying,Jiao, Peng,Williams, David J.,Cohn, Otto-Meth
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- Orthoamides. LIII. A New Synthesis for Aromatic Aldehydes of Wide Scope
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Diformamide (1) reacts with activated aromatic compounds like toluene, anisole, m-xylene, 1,2-dimethoxybenzene in the presence of AlCl3 to give N-(diarylmethyl)-formamides 2a-d, the corresponding aromatic aldehydes 3-6 are formed as by-products in low yields. From N,N-dimethylaniline and 1/AlCl3 the triphenylmethane derivative 7 can be obtained. The reaction of anisole with N-methyl-diformamide (9) affords the formamide 10. The mixture of formamide, P4O10 and AlCl3 reveals to be a reagent which is capable to formylate toluene and anisole, resp. Triformamide (14)/AlCl3 is an effective formylating system which allows the preparation of aromatic aldehydes (e.g. 3,4,17-32) from the corresponding aromatic hydrocarbons. Aluminiumchloride can be replaced by borontrichloride. The yields of the formylation reactions depend strongly from the reaction conditions (molar ratio: aromatic hydrocarbon/ AlCl3/14; solvent, reaction temperature). The scope of the reaction covers nearly complete those of the Gattermann-Koch-, Gattermann- and Vilsmeier-Haack-reaction.
- Kantlehner, Willi,Vettel, Markus,Gissel, Alexander,Haug, Erwin,Ziegler, Georg,Ciesielski, Michael,Scherr, Oliver,Haas, Richard
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p. 297 - 310
(2007/10/03)
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- Effect of BSA binding on photophysical and photochemical properties of triarylmethane dyes
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We have employed a combination of steady-state and time-resolved spectroscopic techniques to explore the effect of protein binding on the photophysical and photochemical properties of three triarylmethane dyes: ethyl violet, crystal violet, and malachite green. Our results indicate that the binding sites of bovine serum albumin (BSA) are very efficient in preventing fast nonradiative relaxation processes that occur via rotational motion of the aromatic rings of these triarylmethanes. As a result, remarkable enhancements in fluorescence quantum yield and lifetime, intersystem crossing efficiency, and photoreactivity are observed upon protein binding. The 532 nm laser-induced photobleaching of ethyl violet noncovalently bound to BSA yields leuco ethyl violet and 4,4a?2-bis(diethylamino)benzophenone as reaction products. The former was more prominent in nitrogen-purged samples and the latter in air-equilibrated samples. The time-resolved transient spectra of the ethyl violet complex show superimposed elements of the spectroscopic signatures of both ethyl violet triplet and the semireduced dye radical. Based on the nature of the reaction photoproducts and transient intermediates, the first step of the bleaching process is postulated to be an electron or hydrogen atom transfer from the protein to the dye moiety. An analogous reaction mechanism was observed for protein-bound crystal violet.
- Baptista, Mauricio S.,Indig, Guilherme L.
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p. 4678 - 4688
(2007/10/03)
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- Montmorillonite clay catalysis VI: Synthesis of triarylmethanes via Baeyer condensation of aromatic aldehydes with N,N-dimethylaniline catalysed by montmorillonite K-10
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Triarylmethanes are synthesized in good to excellent yield via Baeyer condensation of aromatic aldehydes with N,N-dimethylaniline catalysed by montmorillonite K 10 at 100°C in the absence of solvent.
- Zhang, Zhan-Hui,Yang, Feng,Li, Tong-Shuang,Fu, Cheng-Guang
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p. 3823 - 3828
(2007/10/03)
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- The incremental approach to noncovalent interactions: Coulomb and van der waals effects in organic ion pairs
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The equilibria of 10 ion pairs with aromatic units in one or both ions are determined in water by UV/vis and partially by NMR and conductivity experiments, showing in most cases satisfactory agreement. UV/vis measurements at different wavelengths usually exhibit weaker 1:2, in addition to 1:1, complexes. On the basis of a generalized principle of additive binding increments, the results from about 40 ion pairs - many from the literature - show a surprisingly constant Coulomb increment of ΔG = 5 ± 1 kJ/mol per single salt bridge. The van der Waals forces in the aromatic ion pairs also lead to a linear increase of the complexation strength with the number of aryl groups in the complexes. A corresponding two-term correlation yields, in agreement with other studies, a vdW increment of 1-2 kJ/mol per aryl unit, which is shown to be due to ion-induced dipoles in the π-system. Conformations were partially modeled with force field calculations (CHARMm); they are in qualitative agreement with complexation-induced shifts obtained from NMR titrations. The CIS-NMR values explain deviations from the correlations for three ion pairs due to steric hindrance and contradict edge-to-face arrangements of benzene rings. Charge-transfer (CT) interactions, although visible in typical UV/vis absorptions, do not contribute significantly (0.5 kJ/mol) to the associations. Selected measurements with less polar solvents added show the expected binding increase but no correlation with the bulk dielectric constant.
- Schneider, Hans-J?rg,Schiestel, Thomas,Zimmermann, Patrick
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p. 7698 - 7703
(2007/10/02)
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- First Reactions of Dialkoxycarbenium Tetrafluoroborates with Pyrroles, 5H-Dibenzazepines, and Electron-Rich Arenes
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Pyrrole (2a) and 2,5-dimethylpyrrole (2b) react with the dialkoxycarbenium tetrafluoroborates 1a-1c under kinetic control to yield the corresponding acylpyrrole derivatives. 5H-Dibenzazepine (9a) and the 10,11-dihydro derivative 9b react only with the most elecrophilic of the series of electrophiles tested, namely, diethoxycarbenium tetrafluoroborate (1a), to furnish the corresponding formyl derivatives.Similarly, in arene chemistry, the highly electron-rich N,N-dimethylaniline (13a) and 1,3,5-trimethoxybenzene (13b) are formylated by reaction with 1a.
- Pindur, U.,Flo, C.
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p. 1563 - 1568
(2007/10/02)
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- PHOSPHORUS-NITROGEN COMPOUNDS. PART 48. THE REACTIONS OF N,N-DIMETHYLTOLUIDINES WITH PHOSPHORUS(V) CHLORIDES. FORMATION OF A NOVEL HETEROCYCLIC SYSTEM.
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The reactions of phosphorus oxychloride, P(O)Cl3, with the three N,N-dimethyltoluidines have been studied.O-toluidine gave after suitable work-up only a "nitrogen-substituted" derivative, P(O)(NMeC6H4Me-2)(OEt)2, whilst the m-analogue gave both "nitrogen-substituted", P(O)(NMeC6H4Me-3)(OEt)2, and "carbon-substituted" products, P(O)(C6H3Me-2-NMe2-4)2(OEt), as well as two purely organic compounds, CH2(C6H3Me-2-NMe2-4)2 and CH(C6H3Me-2-NMe2-4)3.With N,N-dimethyl-p-toluidine in addition to two acyclic 'nitrogen-substituted' products, P(O)(NMeC6H4Me-4)(OEt)2 and P(O)(NMeC6H4Me-4)2(OEt), the chloro- and ethoxy-derivative of a novel eight-membered heterocyclic system, P(O)X (X = Cl or OEt), as well as two organic products, CH2(C6H3Me-5-NHMe-2)2 and CH2(C6H3Me-5-NMe2-2)-(C6H3Me-5-NHMe-2) were isolated.The reaction of thiophosphoryl chloride, P(S)Cl3, with N,N-dimethyl-p-toluidine also gave a similar heterocycle, P(S)Cl.The 1H NMR spectra are discussed and related to the X-ray crystal structures.
- Cheng, Ching Yee,Shaw, Robert A.
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p. 185 - 192
(2007/10/02)
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- Reduction of Crystal Violet by Diphenylketyl Radicals
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Crystal violet (CV+) is stable to direct photolysis in acetonitrile at λirr >/= 366 nm even in the presence of hydrogen donors (benzhydrol and 2-propanol).However, when benzophenone (K) is present in samples containing hydrogen donor and λirr + by diphenylketyl (KH.) followed by hydrogen transfer to the intermediate CV. with formation of the leuco dye (CVH) is proposed.The rate constant (k6) for the electron transfer reaction CV+ + KH. -> CV. + K + H+, k6 = 6 +/- 2 x 105 M-1 s-1 (6) has been determined by two methods both of which rely on the competition between reactions 5 and 6 2KH. -> K2H2, k5 = 1.05 +/- 0.02 x 108 M-1 s-1 (5) In the first the quantum yield of sensitized fading is determined as a function of CV+ concentration.In the second the rates of benzpinacol formation in the absence and presence of CV+ are followed.
- Naguib, Yousry M. A.,Cohen, Saul G.,Steel, Colin
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p. 128 - 133
(2007/10/02)
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- Process for the preparation of triarylmethane compounds
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A process for the preparation of triarylmethane compounds which comprises reacting a benzene or naphthalene compound with a formylating agent for such compounds in the presence of an acid catalyst to form an aromatic aldehyde compound; adding water to the reaction mixture and thereby hydrolyzing the acid catalyst without isolating the aromatic aldehyde compound from the reaction mixture; and uninterruptedly condensing the aromatic aldehyde compound with an aromatic compound in the resulting mixture.
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- KINETIC ISOTOPE AND PRESSURE EFFECTS IN THE REACTION OF LEUCOCRYSTAL VIOLET WITH TETRACYANOETHYLENE AND CHLORANIL.
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The rates of reaction of Leucocrystal Violet (LCV) with chloranil (CA) and tetracyanoethylene (TCNE) were measured, and the kinetic isotope and pressure effects were examined. In the LCV-CA system, a very large isotope effect was observed, while in the LCV-TCNE system, it was not so large (k//H/k//D equals 5-6) suggesting the tunnel effect is not substantial. For both systems, the formation of a CT complex in equilibrium with the reactants was observed at low temperatures ( less than minus 50 degree C). From the rate law, the isotope effect, the electronic and ESR spectra observed during the reaction, and their time dependence, possible reaction processes are proposed.
- Nishimura,Motoyama
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- Photooxidation of Leuco Dyes. VIII. Time Resolved Investigations of the Mechanism of the Photooxidation of Leucocrystal Violet
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The photooxidation of leucocrystal violet has been reexamined by means of conventional and laser flash photolysis as well as spin trap experiments.Three radical transients have been observed and assigned to the caton radical (λmax ca. 490, 530 nm), the neutral radical with one -NCH3-CH2 moiety (λmax ca. 480 nm) and the triphenyl methyl radical derivative (λmax ca. 400 nm).
- Hinzmann, G.,Grummt, U.-W.,Paetzold, R.
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p. 899 - 909
(2007/10/02)
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- THE INTERVENTION OF OXYGEN IN THE OXIDATION OF N,N-DIMETHYLANILINES WITH FENTON'S REAGENT
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N-Dealkylation and nuclear hydroxylation are observed in the treatment of N,N-dimethylanilines with iron(II) and hydrogen peroxide.Oxygen is consumed during the oxidation.Although oxygen activation depends upon pH and concentration of both substrate and hydrogen peroxide, deuterium labelling of substrates and measurements of oxygen consumption provide some information on the mechanism of its activation.
- Galliani, Guido,Rindone, Bruno
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p. 207 - 212
(2007/10/02)
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- Photochemical Reactions of Bromoanthracenes with N,N-Dimethylaniline in Solution
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Major products of the photolysis of 9-bromoanthracene and 9,10-dibromoanthracene in benzene and acetonitrile as well as photochemical reaction products of the two bromoanthracenes with N,N-dimethylaniline in these solvents have been isolated and identified.The mechanisms of partial reactions are discussed and attention is paid to the medium effect on the photochemical transformations. - Keywords: Photochemical Reactions, Bromoanthracenes
- Fulara, Jan,Latowski, Tadeusz
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p. 846 - 851
(2007/10/02)
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- SYNTHESIS OF AROMATIC ALDEHYDES VIA 2-ARYL-N,N'-DIACYL-4-IMIDAZOLINES
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Diacylimidazolium ions yield adducts with aromatic compounds.Thus the N,N'-diacetylimidazolium ion and indole gives 1,3-diacetyl-2-(3-indolyl)-4-imidazoline.Less reactive substrates such as thiophene, anisole and 1,3-dimethylbenzene fail to react with this reagent but do form adducts (e.g. 1,3-bis-(trifluoroacetyl)-2-(2-thienyl)-4-imidazoline) with an imidazole/trifluoroacetic anhydride reagent.All of the adducts could be converted to the corresponding aldehyde under mild conditions.The synthetic scope of the new synthesis is similar to that of the Vilsmeier-Haack reaction.
- Bergman, Jan,Renstroem, Lars,Sjoeberg, Birger
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p. 2505 - 2512
(2007/10/02)
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