- Oxidative Dehomologation of Aldehydes with Oxygen as a Terminal Oxidant
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A mild, efficient protocol for oxidative cleavage of C-C bonds in aldehydes has been developed that employs alkali metal hydrides as reagents and oxygen from air as a terminal oxidant. The method is applicable to a broad substrate range.
- Shipilovskikh, Sergei A.,Rubtsov, Aleksandr E.,Malkov, Andrei V.
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supporting information
p. 6760 - 6762
(2017/12/26)
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- Synthesis, spectral investigation of Ni(II) schiff base complexes: Antimicrobial activities and catalytic oxidation of alcohols
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Air stable Ni(II) Schiff base complexes viz. [Ni(L1)(PPh3)] and [Ni(L2)(PPh3)] [where L1 and L2 are dianions of Schiff base ligands, respectively] have been synthesized and characterized by analytical and spectral (electronic, FT-IR, 1H, 13C and 31P NMR) methods. The assignment of all the aromatic carbon-hydrogen resonances is made on the basis of 1H-13C HSQC spectrum of the complexes. The Schiff base ligands behave as a bibasic tridentate ligands and bonded through ONO and ONS mode. A square planar structure has been proposed on the basis of spectral data. Novel Ni(II) Schiff base complexes exhibited good antimicrobial activity towards the strains Staphylococcus epidermidis and Escherichia coli. Thermal and air stability of the complexes offer the advantage of oxidation of alcohols.
- Madaselvi,Padma Priya,Jeyaraj,Arun Paul,Kalaivani,Shahul Meeran,Arunachalam
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p. 1682 - 1686
(2016/07/06)
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- Copper(I)/ABNO-catalyzed aerobic alcohol oxidation: Alleviating steric and electronic constraints of Cu/TEMPO catalyst systems
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Cu/TEMPO catalyst systems promote efficient aerobic oxidation of sterically unhindered primary alcohols and electronically activated substrates, but they show reduced reactivity with aliphatic and secondary alcohols. Here, we report a catalyst system, consisting of (MeObpy)CuI(OTf) and ABNO (MeObpy =4,4′-dimethoxy-2,2′-bipyridine; ABNO = 9-azabicyclo[3.3.1]nonane N-oxyl), that mediates aerobic oxidation of all classes of alcohols, including primary and secondary allylic, benzylic, and aliphatic alcohols with nearly equal efficiency. The catalyst exhibits broad functional group compatibility, and most reactions are complete within 1 h at room temperature using ambient air as the source of oxidant.
- Steves, Janelle E.,Stahl, Shannon S.
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supporting information
p. 15742 - 15745
(2013/11/06)
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- 2-Iodoxybenzoic acid organosulfonates: Preparation, X-ray structure and reactivity of new, powerful hypervalent iodine(v) oxidants
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New powerful hypervalent iodine(v) oxidants, tosylate and mesylate derivatives of 2-iodoxybenzoic acid (IBX), were prepared by the reaction of IBX with the corresponding sulfonic acids. Single crystal X-ray crystallography of the diacetate derivative of IBX-tosylate revealed an unusual heptacoordinated iodine geometry without any significant intermolecular secondary interactions.
- Yusubov, Mekhman S.,Svitich, Dmitrii Yu.,Yoshimura, Akira,Nemykin, Victor N.,Zhdankin, Viktor V.
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supporting information
p. 11269 - 11271
(2013/12/04)
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- Facile preparation and reactivity of bifunctional ionic liquid-supported hypervalent iodine reagent: A convenient recyclable reagent for catalytic oxidation
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Novel, efficient, and recyclable bifunctional catalysts bearing ionic liquid supported (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and iodoarene moieties were developed and used for environmentally benign catalytic oxidation of alcohols. The reactions using peracetic acid as a green and practical co-oxidant afforded the corresponding carbonyl compounds in high yields under mild conditions and convenient work-up. Furthermore, these ionic liquid supported bifunctional catalysts could be simply recovered and reused.
- Zhu, Chenjie,Yoshimura, Akira,Wei, Yunyang,Nemykin, Victor N.,Zhdankin, Viktor V.
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supporting information; experimental part
p. 1438 - 1444
(2012/04/04)
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- Facile preparation and reactivity of polystyrene-supported (dichloroiodo)benzene: A convenient recyclable reagent for chlorination and oxidation
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A facile one-pot preparation of polystyrene-supported (dichloroiodo)benzene (loading of -ICl2 up to 1.35 mmol/g) from polystyrene, iodine, and bleach has been developed. This recyclable reagent is useful for efficient chlorination of organic substrates and selective oxidation of various alcohols to the corresponding carbonyl compounds in high yields under mild conditions. The final products are conveniently separated from the polymeric byproduct by simple filtration and isolated in good purity after evaporation of solvent.
- Chen, Jiang-Min,Zeng, Xiao-Mei,Middleton, Kyle,Zhdankin, Viktor V.
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supporting information; experimental part
p. 1952 - 1955
(2011/04/25)
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- Fe (III) complexes of a bis-benzimidazolyl diamide ligand: Spectral and Catalytic studies
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A new tetradentate bis benzimidaozlyl diamide ligand N,N′-Bis (benzimidazol-2-yl-methyl)-hexane-1,6-dicarboxamide (GBSA) has been synthesized and utilized to prepare new Fe(III) complexes with exogenous anionic ligand X = Cl- and NO3-. Isomer shift values are in the range found for Iron in the +3 oxidation state while Quadrupole Splitting indicates large distortion from a six coordinate geometry, a finding supported by low temperature EPR work. The E1/2 values are found to be quite cathodic indicating stability of the Iron (III) complexes. The oxidation of alcohols was investigated using [Fe(GBSA)Cl3] as the catalyst with TBHP as an alternate source of oxygen. The respective carbonyl products have been isolated and characterized by 1H NMR, electronic spectroscopy, mass and IR spectral studies.
- Ahuja, Gauri,Mathur, Pavan
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body text
p. 180 - 186
(2011/12/22)
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- Synthesis, characterization, redox, catalytic, and antibacterial activities of binuclear ruthenium(III) schiff base complexes containing triphenylphosphine as co-ligand
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New hexa-coordinated binuclear Ru(III) Schiff base complexes of the type [(PPh3)2X2Ru]2L (where, X = Cl or Br; L = binucleating N2O2 Schiff bases) have been synthesized and characterized by elemental analysis, magnetic susceptibility measurement, FT-IR, UV-vis, 13C1H-NMR, ESR, cyclic voltammetric, SEM and powder X-ray diffraction pattern. The new complexes have been used as catalyst in C C coupling reaction and the oxidation of alcohols to their corresponding carbonyl compounds by using molecular oxygen atmosphere at ambient temperature. Further, the new Schiff base ligands and their Ru(III) complexes were also screened for their antibacterial activity against K. pneumoniae, Shigella sp., M. luteus, E. coli and S. typhi. From this study, it was found out that the activity of the ruthenium(III) Schiff base complexes almost reaches the effectiveness of the conventional bacteriocide standards. Copyright Taylor & Francis Group, LLC.
- Manimaran, Arumugam,Jayabalakrishnan, Chinnasamy
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experimental part
p. 116 - 128
(2010/08/13)
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- Efficient solvent-free synthesis of thiazolidin-4-ones from phenylhydrazine and 2,4-dinitrophenylhydrazine
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An efficient solvent-free synthesis of thiazolidinones from reaction of mercaptoacetic acid, aldehydes (benzaldehyde and valeraldehyde) or ketones (cyclopentanone and cyclohexanone), and hydrazines (phenylhydrazine and 2,4-dinitrophenylhydrazine) is reported. The compounds were generally characterized by spectroscopic techniques and specifically for 2-cyclohexanyl-3-(N-phenyl)-1,3-thiazolidin-4-one by X-ray crystallography.
- Neuenfeldt, Patrícia D.,Drawanz, Bruna B.,Siqueira, Geonir M.,Gomes, Claudia R.B.,Wardell, Solange M.S.V.,Flores, Alex F.C.,Cunico, Wilson
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supporting information; experimental part
p. 3106 - 3108
(2010/07/18)
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- Biocidal and catalytic efficiency of ruthenium(III) complexes with tridentate Schiff base ligands
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The reaction of the Schiff bases (obtained by condensing isatin with o-aminophenol/o-aminothiophenol/o-aminobenzoic acid) with [RuX 3(EPh3)3] (where X = Cl/Br; E = P/As) in benzene afforded new, air-stable Ru(III) complexes of the general formula [Ru(L)X(EPh3)2] (L = dianion of tridentate Schiff bases). In all these reactions, the Schiff base ligand replaces one triphenylphosphine/ triphenylarsine and two chlorides/bromides from the ruthenium precursors. The complexes were characterized by elemental analyses, spectral (FT-IR, UV-vis,1H and 13C NMR for the ligands, and EPR) and electrochemical studies. All the metal complexes exhibit characteristic LMCT absorption bands in the visible region. The catalytic reactivity proved these complexes to be efficient catalysts in the oxidation of alcohols and C-C coupling. All the complexes were screened for their biocidal efficiency against bacteria such as Staphylococcus epidermidis and Escherichia coli and fungi such as Botrytis cinerea and Aspergillus niger at 0.25,0.50 and 1 % concentrations.
- Arunachalam,Priya, N. Padma,Boopathi,Jayabalakrishnan,Chinnusamy
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experimental part
p. 491 - 498
(2010/10/18)
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- COMPOSITIONS CAPABLE OF INHIBITING REACTIVE OXYGEN AND CARBONYL SPECIES
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Therapeutic compositions are provided. The compositions include a single molecule that can display both antioxidant and carbonyl trapping properties. This can effectively reduce inflammation, oxidative stress and carbonyl stress, such as to prevent and/or treat cardiovascular disease and inflammatory diseases in kidney disease patients.
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Page/Page column 25
(2010/10/20)
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- Ferric(III) nitrate supported on kieselguhr: A new reagent for selective oxidation of alcohols
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A selective and effective oxidation of alcohols into the corresponding aldehydes and ketones, respectively, with a new reagent, ferric(III) nitrate supported on kieselguhr, under heterogeneous conditions is reported. Copyright Taylor & Francis Group, LLC.
- Lou, Ji-Dong,Zhu, Long-Hua,Ma, Yi-Chun,Li, Li
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p. 3061 - 3064
(2007/10/03)
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- Synthesis and properties of 4,9-methanoundecafulvenes and their transformation to 3-substituted 7,12-methanocycloundeca[4,5]furo[2,3-d] pyrimidine-2,4(1H,3H)-diones: Photo-induced autorecycling oxidizing reaction toward amines
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The synthesis and properties of 4,9-methanoundecafulvene [5-(4,9-methanocycloundeca-2′,4′,6′,8′, 10′-pentaenylidene)pyrimidine-2,4,6(1,3,5H)-trione] derivatives 8a,b were studied. Their structural characteristics were investigated on the basis of the 1H and 13C NMR and UV-vis spectra. The rotational barrier (ΔG?) around the exocyclic double bond of 8a was found to be 12.55 kcal mol-1 by the variable temperature 1H NMR measurement. The electrochemical properties of 8a,b were also studied by CV measurement. Furthermore, the transformation of 8a,b to 3-substituted 7,12-methanocycloundeca[4,5]furo[2,3-d]pyrimidine-2,4(1H,3H)-diones 16a,b was accomplished by oxidative cyclization using DDQ and subsequent ring-opening and ring-closure. The structural details and chemical properties of 16a,b were clarified. Reaction of 16a with deuteride afforded C13-adduct 19 as the single product, and thus, the methano-bridge controls the nucleophilic attack to prefer endo-selectivity. The photo-induced oxidation reaction of 16a and a vinylogous compound, 3-methylcyclohepta[4,5]furo[2,3-d]pyrimidine-2,4(3H)-dione 2a, toward some amines under aerobic conditions were carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) with the recycling number of 6.1-64.0 (for 16a) and 2.7-17.2 (for 2a), respectively.
- Naya, Shin-Ichi,Yamaguchi, Yohei,Nitta, Makoto
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p. 7384 - 7391
(2007/10/03)
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- Dowex polymer-mediated protection of carbonyl groups
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Dowex (strongly acidic cationic exchange resin) polymer is employed as solid acid catalyst for the clean and less hazardous protection of carbonyl compounds as phenylhydrazones and 2,4-dintrophenylhydrazones in ethanol under reflux conditions. The reactions proceed very smoothly and the yields of the derivatives are excellent. Copyright Taylor & Francis, Inc.
- Niknam, Khodabakhsh,Kiasat, Ali Reza,Karimi, Sadegh
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p. 2231 - 2236
(2007/10/03)
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- In situ alcohol oxidation-protection reactions
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The one-pot conversion of primary and secondary alcohols into phenylhydrazones and 2,4-dintrophenylhydrazones is reported using chromium trioxide supported on silica gel and phenylhydrazines or 2,4- dintrophenylhydrazines under solvent-free conditions. This oxidation arylhydrazone formation reaction has been applied to a range of aliphatic and benzylic alcohols. Copyright Taylor & Francis, Inc.
- Kiasat,Kazemi,Nourbakhsh
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p. 1555 - 1558
(2007/10/03)
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- Novel synthesis, properties, and NAD+-NADH type redox ability of 1,3-dimethylcyclohepta[4,5]pyrrolo[2,3-d]pyrimidine-2,4(1,3H)-dionylium ions annulated with additional pyrrolo[2,3-d]pyrimidine-1,3(2,4H)-dione and furan analogue, and their hydride adducts
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A convenient preparation of novel cations 11a,b+·BF 4- and 12a,b+·BF4 -, which are derived from annulation of the 1,3-dimethylcyclohepta[4, 5]pyrrolo[2,3-d]pyrimidine-2,4(1,3H)-dionylium ion with additional pyrrolo[2,3-d]pyrimidine-1,3(2,4ii)-dione and a furan analogue, was accomplished by a novel oxidative cyclization of 1,7-dihydro-7-[1′,3′-dimethyl- 2′,4′(1′,3′H)-dioxo-6′-(phenylamino) -pyrimidin-5′-yl]-1,3-dimethyl-10-phenylcyclohepta[4,5]pyrrolo[2,3-d] pyrimidine-2,4(1,3H)-dione 9 and its furan-analogue by using DDQ or photoirradiation under aerobic conditions. Structural characteristics of 11a,b+ and 12a,b+ were clarified on inspection of the UV-vis and NMR spectral data as well as X-ray crystal analyses. The stability of cations 11a,b+ and 12a,b+ is expressed by the pK R+ values that were determined spectrophotometrically to be 10.7-12.6. The electrochemical reduction of 11a,b+·BF 4 and 12a,b+·BF4- exhibited reduction potential at -0.93 to -1.00 (V vs Ag/AgNO3). The first reduction potential of 11a+ was reversible due to steric hindrance of two phenyl groups. The photoinduced oxidation reaction of 11a,b +·BF4- and 12a,b+· BF4- toward some amines under aerobic conditions was carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) with the recycling numbers of 0.6-30.3. Furthermore, as an example of the NAD+-NADH models, the reduction of a pyruvate analogue and some carbonyl compounds with the hydride-adduct of 11a+-BF4- was accomplished for the first time to give the corresponding alcohol derivatives.
- Naya, Shin-Ichi,Nishimura, Junya,Nitta, Makoto
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p. 9780 - 9788
(2007/10/03)
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- Novel Synthesis and Properties of 1,6-Methanocycloundeca[b]pyrimido[5,4-d]pyrrole-12,14-dione Derivatives: Autorecycling Oxidation of Some Amines and Alcohols
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Novel 1,6-methanocycloundeca[b]pyrimido[5,4-d]pyrrole-12,14-dione derivatives 6a,b and 7a-c were synthesized in moderate to good yields by the enamine alkylation and dehydrating condensation reactions of 11-chloro-3,8-methano [11] annulenone (8) with 6-amino-3-substituted uracil derivatives and subsequent elimination of HCl. The 1H NMR spectra clarified that compounds 6a,b and 7a-c are aromatic molecules having a diatropic π-system, which is suggested by the chemical shifts of the bridge methylene protons and peripheral protons. The electrochemical reduction exhibited more positive reduction potentials as compared with those of the vinylogous compounds of cyclohepta-[b]pyrimido[5,4-d]pyrrole derivatives. In a search for the oxidizing function of 6a,b and 7a-c, compounds 6a and 7b were demonstrated to oxidize benzylamines, cyclohexylamine, and benzyl alcohol to give the corresponding carbonyl compounds in more than 100% yield under aerobic and photoirradiation conditions, while only benzylamine was oxidized under aerobic and thermal conditions at 100 °C. Thus, compounds 6a and 7b oxidize amines and alcohols in an autorecyling process, and the efficiency is higher under photoirradiation as compared with the thermal process, suggesting the oxidation reaction probably proceeds via electron transfer from amine and alcohol to the excited and ground states of compounds 6a and 7b.
- Mitsumoto, Yuhki,Nitta, Makoto
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p. 1256 - 1261
(2007/10/03)
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- Novel synthesis and oxidizing ability of tropylium ions annulated with two 2,4-dimethylfuro[2,3-d]pyrimidine-1(2H),3(4H)-diones
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Convenient preparation of novel tropylium ions annulated with two 2,4-dimethylfuro[2,3-d]pyrimidine-1(2H),3(4H)-diones, 12a+· BF4- and 12b+·BF4 -, consists of a reaction of 2-methoxytropone with dimethylbarbituric acid to give 7,9-dimethyl-3-[1′,3′-dimethyl-2′(1′H), 4′(3′H),6′(5′H)-trioxopyrimidin-5′-ylidene] cyclohepta[b]pyrimido[5,4-d]furan-8(7H),10(9H)-dione 8 and the following oxidative cyclization by using DDQ or photoirradiation under aerobic conditions. On the basis of the MO calculations, the selectivity of two types of oxidative cyclization reactions of 8 was rationalized. X-ray crystal analyses and MO calculations were carried out to clarify the structural characteristics of 12a+·BF4- and 12b+· BF4-. The stability of cations 12a+ and 12b+ is expressed by the pKR+ values which were determined spectrophotometrically as 8.8 and 8.6. The electrochemical reduction of 12a+ and 12b+ exhibited reduction potential at -0.63 and -0.62 (V vs Ag/AgNO3), respectively. Reactions of 12 a+·BF4- and 12b+· BF4- with some nucleophiles, hydride and diethylamine, were carried out to clarify that the reactivity of 12a+· BF4- and 12b+·BF4- was substantially dependent on the annulating position. The oxidizing ability of 12a+·BF4- and 12b+-BF 4- toward alcohols and amines in the autorecycling process was demonstrated as well.
- Naya, Shin-Ichi,Tokunaka, Takeshi,Nitta, Makoto
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p. 4732 - 4740
(2007/10/03)
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- H2SO4/SiO2 as an efficient catalyst for the preparation of phenylhydrazones and 2,4-dinitrophenylhydrazones under solvent-free conditions
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H2SO4 mixed with silica gel (1:1) by weight produces a white powder which is an effective catalyst for the conversion of carbonyl compounds to their corresponding phenylhydrazones and 2,4-dintrophenylhydrazones under solvent-free conditions.
- Kiasat, Ali Reza,Kazemi, Foad,Nourbakhsh, Kazem
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p. 569 - 573
(2007/10/03)
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- New synthesis, properties, and oxidizing ability of 1,3-dimethyl-5,10- methanocycloundeca[4,5]furo[2,3-d]pyrimidin-2,4(1,3H)-dionylium tetrafluoroborate
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A novel synthesis of 1,3-dimethyl-5,10-methanocycloundeca[4,5]furo[2,3-d] pyrimidin-2,4(1,3H)-dionylium tetrafluoroborate (10+·BF 4-) was accomplished by the reaction of 3,8-methano[11]-annulenone with dimethylbarbituric acid and following acidic cyclization, albeit in low yield. Remarkable structural characteristics were suggested on inspection of the spectral data and MO calculation, and it was clarified that the positive charge is largely localized at the C11. The pK R+ value of cation 10+ was determined spectrophotometrically to be 4.6, which is much smaller by 4.1 pH unit than that of 1,3-dimethyl-7,12-methanocycloundeca[4,5]furo[2,3-d]pyrimidin-2,4(1,3H)- dionylium tetrafluoroborate (pKR+ = 8.7). This value is also smaller by 1.6 pH unit than that of the parent 1,6-methano[11]annulenylium ion (pK R+ = 6.2). The feature is rationalized on the basis of the perturbation derived from the bond fixation of the parent cation. The electrochemical reduction of 10+ exhibited less negative reduction potential at -0.39 (V vs Ag/AgNO3) upon cyclic voltammetry (CV). In a search for reactivity, reactions of 10+ with some nucleophiles, hydride and diethylamine, were carried out to give mixtures of C11- and C13-adducts. In both reactions, the methano-bridge controls the nucleophilic attacks to the C13 to favor exo selectivity. The photoinduced autorecycling oxidation reactions of 10+·BF4- toward some amines under aerobic conditions were carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) in 719-3286% yield (recycling number of 10+·BF 4-: 7.2-32.9).
- Naya, Shin-Ichi,Warita, Masato,Mitsumoto, Yuhki,Nitta, Makoto
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p. 9184 - 9190
(2007/10/03)
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- Oxidation of unactivated primary aliphatic amines catalyzed by an electrogenerated 3,4-azaquinone species: A small-molecule mimic of amine oxidases
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High catalytic performance of the electrogenerated amine oxidase mimic 3,4-iminoquinone 1ox is observed under metal-free conditions in the chemoselective oxidation reaction of unactivated primary aliphatic amines.
- Largeron, Martine,Neudorffer, Anne,Fleury, Maurice-Bernard
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p. 1026 - 1029
(2007/10/03)
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- The application of intramolecular radical cyclizations of acylsilanes in the regiospecific formation of cyclic silyl enol ethers
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Acylsilanes with terminal α-stannyl bromide or xanthate functionalities are prepared, α-Stannyl radicals generated from these acylsilanes undergo intramolecular cyclizations to give cyclic silyl enol ethers regiospecifically. The radical processes involve radical cyclization, Brook rearrangement, and β-fragmentation in sequence. A tributylstannyl group serves as the radical leaving group. The newly formed σ-bond and π-bond are located between the same two carbon atoms. This approach is limited to the formation of five-membered rings. In another route, ω-bromo-α-phenylsulfonylacylsilanes are synthesized. The radical cyclizations of these α-sulfonylacylsilanes also give cyclic silyl enol ethers. The phenylsulfonyl moiety is the radical leaving group in this system. Furthermore, the newly formed σ-bond and π-bond are located at adjacent positions sharing a single carbon atom. The latter approach is effective for both five- and six-membered ring formation.
- Huang,Chang,Wang,Tsai
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p. 8983 - 8991
(2007/10/03)
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- A Novel Cleavage of Five-Membered Cyclic Acetals Using Sodium Hydrogen Telluride
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Under mild conditions, a variety of 1,3-dioxolanes are easily cleaved in high yields by treatment with sodium hydrogen telluride in ethanol.
- Lue, Ping,Fan, Wei-Qiang,Zhou, Xun-Jun
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p. 692 - 693
(2007/10/02)
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- The Reactivity of Silyl Ethers to the Swern Reagent
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The activated Me2SO reagent , 'Swern reagent'> oxidises the trimethylsilyl ethers of primary and secondary alcohols directly to the corresponding carbonyl compound.Useful selectivity is possible where competing ether groups possess large differences of steric hindrance.Dimethyl-t-butylsilyl ethers are unaffected by this reagent.
- Afonso, Carlos M.,Barros, M. Teresa,Maycock, Christopher D.
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p. 1221 - 1224
(2007/10/02)
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- A Convenient and Mild Dethioacetalization Method Using Fe(bpy)3(ClO4)3*3H2O
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Reactions of 1,3-dithianes, 1,3-dithiolanes, and benzenethioacetals with tris(2,2'-bipyridyl)iron(III) perchlorate, Fe(bpy)3(ClO4)3*3H2O, gave the parent carbonyl compounds in high yields, immediately.These reactions may proceed by one-electron abstraction from the sulfur atom of acetals by the iron(III) complex, and they provide a new convenient and mild dethioacetalization method.Keywords - dethioacetalization; 1,3-dithiane; 1,3-dithiolane; benzenethioacetal; tris(2,2'-bipyridyl)iron(III) perchlorate; one-elcetron abstraction
- Murase, Masayuki,Kotani, Eiichi,Tobinaga, Seisho
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p. 3595 - 3598
(2007/10/02)
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- o-Nitrophenylethylene glycol as photoremovable protective group for aldehydes and ketones: syntheses, scope, and limitations
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The preparation of o-nitophenylethylene glycol is described along with its application as a photolabile protective group for aldehydes and ketones.Formation of the acetals and ketals is achieved in good to high yields in the usual manner and deprotection is carried out in fair to high yield, by photolysis at 350 nm in an inert solvent such as benzene.Because of the particular nature of the present protective group, its stability to basic and acidic conditions has been examined and is reported to complete the scope and limitations aspect.From a mechanistic point of view, the isolation and characterisation of o-nitroso-α-hydroxyacetophenone as the spent reagent demonstrates a mechanistic link with the known o-nitrobenzaeldehyde to o-nitrobenzoic acid photorearrangement.
- Gravel, D.,Herbert, J.,Thoraval, D.
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p. 400 - 410
(2007/10/02)
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