bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organophosphorus compounds XI: Stereochemistry of grignard displacement reactions at phosphorus in isopropyl methylphosphonohalogenates
Authors: van den Berg G. R. , Platenburg D. H. J. M. , Benschop H. P. 
Published: September 2010

AbstractA series of stereospecific reactions, starting from (−)‐(isoPrO)MeP(O)H (I) (see Reaction Scheme), establishes that the absolute configuration of (+)‐(isoPrO)‐MeP(O)SMe(II) (R′=Me) is (R), and not (S) as previously suggested. The reassigned configuration is confirmed by X‐ray analysis. It follows that the displacement of X by Ph in isoPrO(Me)P(O)X proceeds with complete retention of configuration when X = SMe, but proceeds with complete inversion when X = F. In the case of X = Cl, the reaction proceeds at least predominantly with inversion of configuration.
The reduction of alkylnaphthalenes with lithium in liquid ammonia
Authors: Nieuwstad Th. J. , van Bekkum H. 
Published: September 2010

AbstractThe reduction of naphthalene and alkylnaphthalenes with lithium in liquid ammonia has been studied. With excess of alkali metal and in the absence of a proton donor the reaction yields tetralins. The reduction of 1, 4‐dideuteronaphthalene shows that the first proton addition at an α‐position is irreversible and that the amide‐catalyzed isomerization of the initially formed 1, 4‐ into the 1, 2‐dihydronaphthalene is mainly a one step process. This isomerization is the rate‐determining step in the reduction to tetralin. Reduction of 1‐alkyl‐ and 1, 4‐dialkyl‐naphthalenes occurs mainly in the unsubstituted ring. With 2‐alkyl‐naphthalenes the selectivity of ring reduction depends on the alkyl group; in 2‐methylnaphthalene the substituted ring is about twice as reactive as the unsubstituted ring whereas the reverse is true for 2‐t‐butylnaphthalene.
Vibrational spectra and structure(s) of some X(SR)4 molecules with X  C, Si, Ge, Sn and R = methyl, ethyl, isopropyl
Authors: Ypenburg J. W. , Gerding H. 
Published: September 2010

AbstractThe vibrational spectra (Raman and infrared) of tetrakis (methylthio) methane, tetrakis (ethylthio) methane, tetrakis (methylthio) silane, tetrakis (methylthio) germane and tetrakis (methylthio) stannane have been recorded and analyzed with an assignment of the frequencies observed. The vibrational spectrum of tetrakis‐ (isopropylthio) methane has been obtained also.The liquid states of tetrakis (methylthio) methane (TMC), – silane (TMSi) and ‐ germane (TMGe) contain probably two rotamers; liquid and solid tetrakis‐(methylthio) stannane (TMSn) contain probably one configuration in which internal rotation is nearly free.Solid TMC shows a remarkable behaviour concerning the rotamers: modification 1, which is stable at temperatures below 23°, contains only the D2d configuration; modification 2, stable between 23° and 46°, contains only the S4 configuration and modification 3, stable between 46° and the melting point, consists of a mixture of both configurations.Rotamers present in solid and liquid tetrakis (ethylthio) methane (TEC) are at least partly different. Raman spectra of solid TEC at temperatures above and below the transition point at ‐ 94° are identical within errors of measurement.Solid TMSi and TMGe consist in all probability of one of the rotamers present in the liquid.
Pyrazoles IX. Nitration of 1‐methyl‐4‐phenylpyrazole
Authors: Cohen‐Fernandes Pauline , Habraken Clarisse L. 
Published: September 2010

AbstractIn contrast to nitration with nitric acid in sulfuric acid giving 4‐(o,p‐dinitrophenyl)‐l‐methylpyrazole 2, both the phenyl and the pyrazole ring are substituted on nitration with acetyl nitrate. With the latter method also a predominant ortho substitution in the phenyl ring is observed. It is concluded, that the pyrazole ring is quite susceptible to nitration at positions other than the, hitherto favoured, 4‐position.
Activity coefficients of single ions (V) in acetone and acetone‐water mixtures
Authors: Bax D. , de Ligny C. L. , Remijnse A. G. 
Published: September 2010

AbstractA method for the estimation of standard chemical potential differences (Δμ°) of single ions for the transfer from one solvent to another, described previously, is further improved and applied to the transfer from water to acetone and acetone‐water mixtures.With some reservation a value of the surface potential χ of acetone is derived.
Folded conformations. Part III: An NMR study of the conformations of aryl N‐arylsulfonylmethyl)‐N‐methylcarbamates
Authors: van Est‐Stammer Renee , Engberts Jan B. F. N. 
Published: September 2010

AbstractIntramolecular shielding effects observed in the NMR spectra of the aryl N‐(arylsulfonylmethyl)‐N‐methylcarbamates 1‐7 and of phenyl N‐hydroxy‐N‐(p‐tolylsulfonylmethyl)carbamate 8 are interpreted in terms of the occurrence of folded conformations in which the aryl rings are in proximity of each other. The 2′,6′‐protons of the ester aryl group are more upfield shifted than the 3′,5′‐protons, whereas the protons of the aromatic ring attached to the sulfonyl moiety experience no significant shifts. These results indicate that the planes of the aryl rings make an angle with each other. In one case (3) the long wave‐length UV absorption was indicative for weak intramolecular CT interaction between the aromatic rings. Stereochemical information concerning the equilibrium conformation around the NCH2 bond was provided by the ESR spectra of the nitroxide 19 (derived from 8) at variable temperatures using the magnitude of the β‐H hyperfine splitting constant as a probe for conformational preferences.
Preparation and properties of Ni(IV), Pd(IV) and Pt(IV) trisdithiocarbamato complexes
Authors: Willemse J. , Cras J. A. 
Published: September 2010

AbstractOxidation of N,N‐dialkyldithiocarbamato (R2dtc) complexes of Ni(II), Pd(II) and Pt(II) with 3,5‐bis(N,N‐dialkyliminium)‐1,2,4‐trithiolane ion (R4bitt)2+ containing compounds and with M(R2dtc)X2 (M = Cu, Au; X = Cl, Br) is reported. From the oxidation of Ni(R2dtc)2 the componds Ni(R2dtc)3X (X = Cl, Br, FeCl4) were obtained. The oxidation of Pd(R2dtc)2 with R4bitt2+Cu2X2−6 (X = Cl, Br) resulted in the new compounds [Pd(R2dtc)3]2Cu2X6.The new compound Pt(R2dtc)3CuBr2 could be obtained by the oxidation of Pt(R2dtc)2 with either (R4bitt)2+Cu2Br2−6 or Cu(R2dtc)Br2, or by the reaction of Pt(R2dtc)3Br with CuBr2. The analogous copper chloride compound was prepared from (R4bitt)2+Cu2Cl2−6 with Pt(R2dtc)2. The compound Pt(R2dtc)3AuBr2 was prepared from Pt(R2dtc)2 and Au(R2dtc)Br2. The metal‐sulfur infrared stretching frequencies are in accord with the assumption that in all these compounds the metal atoms Ni(IV), Pd(IV) and Pt(IV) have a D3 symmetry. Conductivity measurements showed the platinum complexes to be 1:1 electrolytes.
Concentration and distribution of nucleic acids in normal and atherosclerotic human aortas
Authors: Klynstra F. B. , Rothuis‐ ter Haar H. A. M. 
Published: September 2010

AbstractQuantitative determinations of the nucleic acids in normal and atherosclerotic human aortic tissues were carried out. Intima (lesions removed), media (lesions removed), fatty streaks and spots, plaques and atheromas of the thoracic aorta at the various stages of atherosclerosis were separately analysed.A marked decrease was found in the deoxynucleic acid (DNA) level in the intima and the media from stage 0 to stage I. The DNA level in the more advanced lesions was significantly lower than that in the surrounding apparently unaffected tissue.From the observed RNA/DNA ratios it is concluded that the RNA content of the tissue‐cells gradually increases in the course of the disease.
The formation of 2‐(dimethylamino)‐3‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one from chlorokojic acid and dimethylamine. The preparation of 2,3,5‐trioxohexanoic acid N,N‐dimethylamide
Authors: Dekker W. H. 
Published: September 2010

AbstractThe reaction of chlorokojic acid with dimethylamine yields 2‐(dimethylamino)‐3‐hydroxy‐6‐methyl‐4H‐pyran‐4‐one in addition to the expected 2‐[(dimethylamino)methyl]‐5‐hydroxy‐4H‐pyran‐4‐one. Upon oxidation the former could be converted into 2,3,5‐trioxohexanoic acid N,N‐dimethylamide.
Photopyro‐ and photoisopyro‐calciferol: Photochemical formation and thermal decomposition
Authors: Bloothoofd‐Kruisbeek A. M. , Lugtenburg J. 
Published: September 2010

AbstractThe thermal “Woodward‐Hoffmann forbidden” reactions of photopyro‐ and photoisopyro‐calciferol and their photochemical formation reactions have been studied.
Synthesis of 1,2‐disubstituted imidazole‐5‐carboxaldehydes and ‐4,5‐dicarboxaldehydes
Authors: Godefroi E. F. , Loozen H. J. J. , Luderer‐Platje J. Th. J. 
Published: September 2010

Abstract1,2‐Disubstituted imidazoles are shown to react with refluxing 37% formaldehyde in acetic acid‐sodium acetate buffer. Both 5‐hydroxymethyl‐ and 4,5‐bishydroxymethyl‐imidazole derivatives may be formed in 25–50% yields. Bis‐hydroxymethylation is favoured by prolonged reaction times and is dependent upon the nature of the C(2) substituent. Oxidation of the mono‐ and dihydroxymethylimidazoles by means of lead tetra‐acetate in pyridine affords the imidazole‐mono‐ and ‐di‐carboxaldehydes. A few reactions of the readily accessible 1‐benzyl‐2‐isopropylimidazole‐4,5‐dicarboxaldehyde with certain ketones and hydrazine, respectively, are described.
Infrared spectra of tetragonal and monoclinic zirconia: (Short communication)
Authors: Erkelens J. , Rijnten H. Th. , Eggink‐ Du Burck S. H. 
Published: September 2010

AbstractDifferent infrared spectra are obtained from samples of monoclinic and tetragonal zirconia. The various infrared bands are assigned to freely vibrating and to interacting surface hydroxyl groups.By exchanging the samples with deuterium gas, acidic sites could be demonstrated on the surface.
Synthesis of guaipyridine and some related sesquiterpene alkaloids
Authors: van Der Gen A. , van Der Linde L. M. , Witteveen J. G. 
Published: September 2010

AbstractSyntheses are described of guaipyridine (8) from guaiol (3) and of epiguaipyridine (2) from α‐gurjunene (10).The alkaloid isolated from Pogostemon patchouli Pellet, possesses structure 8 of guaipyridine.The configuration at C(10) was confirmed by proton magnetic resonance studies on the conformationally rigid tricyclic structures 14 and 15. Natural α‐gurjunene was shown to be a mixture of the C(10)‐epimers 10 and 11.
The oxidation of alkanes to stable carbonium ions by antimony pentafluoride
Authors: Lukas J. , Kramer P. A. , Kouwenhoven A. P. 
Published: September 2010

AbstractAntimony pentafluoride is a unique reagent for the formation of stable carbonium ions by oxidation of saturated hydrocarbons. The kinetic parameters for the abstraction of hydride ion from ethane and neopentane have been determined. Compared to the reactions with mixed Brönsted‐Lewis acid systems (HF‐SbF5, molar ratio ⩾5/1, and FSO3H‐SbF5, molar ratio 1/1), the analogous reactions with pure SbF5 show considerably enhanced reaction rates. Moreover, neat SbF5 is capable of removing the aldehydic proton from aldehydes to yield oxocarbonium ions. It is concluded that for hydride abstraction in the so‐called “magic acid” (FSO3H‐SbF5, molar ratio 1/1) a mechanism involving protonation to alkanonium ions is not the main reaction pathway.
Chiroptical properties of (+)‐ and (−)‐2,6‐dimethyl‐1‐nitrosopiperidine in connection with the sector rule for N‐nitrosoamines
Authors: Maat L. , Beyerman H. C. 
Published: September 2010

AbstractThe sector rule for N‐nitrosoamines predicts a positive Cotton effect for (−)‐(R,R)‐2,6‐dimethyl‐1‐nitrosopiperidine at about 350 nm. The applicability of this rule is doubted in recent publications. We found the chiroptical properties of the title compounds in agreement with the sector rule.
Acid catalyzed hydrolysis of ethoxypropadiene
Authors: de Jonge I. , Drenth W. 
Published: September 2010

AbstractThe acid catalyzed hydrolysis of ethoxypropadiene has been studied in aqueous solution. The reaction is general acid catalyzed and catalytic constants for carboxylic acids conform to the Brønsted relation with an exponent α = 0.62. The average value of the solvent isotope effect k(H3⊕)/k(D3⊕) is 3.05 ± 0.11. These values are similar to corresponding values for vinyl ethers. Proton transfer from acid to substrate is rate‐determining. Zucker‐Hammett and Bunnett parameters suggest, that water is not covalently bound in the transition state of the rate‐determining step.
On the occurrence of the anrorc mechanism in aminations of substituted halogenoaza‐aromatics with potassium amide in liquid ammonia On the mechanism of the reaction of 4‐halogeno‐2,6‐diphenylpyrimidines and of 5‐bromo‐4‐chloro‐2,6‐diphenylpyrimidine with potassium amide in liquid ammonia
Authors: de Valk J. , van der Plas H. C. , de Bode J. W. A. 
Published: September 2010

AbstractEvidence is presented that the amination of 4‐chloro‐2,6‐diphenylpyrimidine with potassium amide in liquid ammonia into the corresponding 4‐amino compound occurs to the extent of about 45% by the ANRORC mechanism. In the amination of the 4‐iodo‐ and 4‐fluoro derivatives of 2,6‐diphenylpyrimidine, however, the ANRORC mechanism is not operative at all. The amination of 5‐bromo‐4‐chloro‐2,6‐diphenylpyrimidine into 4‐amino‐5‐bromo‐2,6‐diphenylpyrimidine occurs to the extent of about 18% by the ANRORC mechanism. The synthesis of 5‐bromo‐4‐chloro‐2,6‐diphenyl‐[1(3)‐15N]pyrimidine and of the 4‐fluoro, 4‐chloro and 4‐iodo derivatives of 2,6‐diphenyl‐[1(3)‐15N]pyrimidine is described.
The wittig rearrangement of (diarylmethoxy)acetamides
Authors: van Der Stelt C. , Heus W.J. , Haasjes A. 
Published: September 2010

AbstractN,N‐Dialkyl‐2‐(arylmethoxy)‐ or N,N‐dialkyl‐2‐(diarylmethoxy)acetamides were found to undergo a Wittig rearrangement under the influence of bases such as sodium hydride to form either N,N‐dialkyl‐3‐aryl‐ or 3,3‐diaryllactamides. When the diarylmethoxy group was asymmetric, the rearrangement resulted in diastereoisomeric reaction products. Ortho substitution in one or both aryl rings altered the course of rearrangement with the result that additionally, or even exclusively, p‐benzylmandelic amide derivatives were formed. Not only rearrangement products but also byproducts like diaryl ketone, diarylmethane and tetraarylethane were formed. The formation of the latter compound would indicate that radicals are somehow involved in the reaction mechanism. To date, attempts to obtain more than circumstantial evidence for such a mechanism have failed. In several cases byproducts with the structure of a substituted p‐benzylbenzoic acid were isolated. These acids were found to arise from the above “para rearrangement” products by further decomposition under the influence of the basic catalyst. The scope of the reaction was explored by studying the rearrangement of some thirty ethers.
Enolization and oxidation: II. Oxidation of ferrocene by molecular oxygen and hydrogen peroxide in acidic media
Authors: Lubach J. , Drenth W. 
Published: September 2010

AbstractFerrocene can be oxidized by molecular oxygen in acidic aqueous ethanol. The rate is first order in oxygen and second order in ferrocene and in acid. Probably, hydrogen peroxide is an intermediate. This hydrogen peroxide is able to oxidize ferrocene and ferricenium ions, but the rates of these reactions are relatively slow. Hydrogen peroxide is removed mainly by reaction with the solvent ethanol. The latter reaction is catalyzed by small amounts of iron ions which originate from decomposition of ferrocene. The presence of this catalytic effect of iron ions in the reaction between hydrogen peroxide and solvent was shown in separate experiments.
A NMR study of N,N,N′,N′‐tetraethylthiuram disulfide and its complexes with ZnI2, CdI2 and HgI2
Authors: Grotens A. M. , Pijpers F. W. 
Published: September 2010

AbstractThe thermodynamic constants of the hindered rotation around the S2CNR2 bond of N,N,N′,N′‐tetraethylthiuram disulfide and its complexes with Zn, Cd and Hg(II) halides have been obtained by NMR.It is shown that the effect of the solvent on the rotation rate is small.At low temperatures the NMR patterns reveal the existence of a second process that interchanges inequivalent ethyl groups. This process is due to the nonequivalence of the ligand sulfur atoms as can be seen from the crystallographic structure of HgI2 (Me4tds). The thermodynamic constants of the interconversion between these two inequivalent configurations are also presented.
Synthesis of substituted 6H‐1,3‐thiazines
Authors: Hoff S. , Blok A. P. 
Published: September 2010

AbstractSubstituted 4,5‐dihydro‐4‐hydroxy‐6H‐1,3‐thiazines II can be prepared in high yields from the BF3 etherate‐catalysed reaction between α,β‐unsaturated aldehydes, ketones and ketols on the one hand and thioamides, thioureas and dithiocarbamates on the other.In some instances these dihydrohydroxythiazines can be converted into the corresponding 6H‐1,3‐thiazines III with POCl3 in pyridine or with acid in aprotic solvents. The conditions of this elimination reaction are discussed.
Conformational preference of cis‐1‐aryl‐2‐(2‐benzo[C]phenanthryl)‐and cis‐1‐aryl‐2‐(3‐phenanthryl)‐ethenes
Authors: de Jong M. H. , Laarhoven W. H. 
Published: September 2010

AbstractNMR measurements under different conditions (temperature, solvents used, presence of a shift‐reagent) of cis‐ and trans‐1‐aryl‐2‐(2‐benzo[c]phenanthryl)‐ethenes reveal that an overcrowded conformation predominates in cis isomers. In the analogous 1‐aryl‐2‐(3‐phenanthryl)ethenes no clear conformational preference is found.
Derivatives of NPCl2(NSOCl)2 and (NPCl2)2NSOCl. Part I: The preparation of a monophenyl and a difluoro derivative of cis‐NPCl2(NSOCl)2
Authors: Baalmann H. H. , van De Grampel J. C. 
Published: September 2010

AbstractReaction of NPCl2(NSOCl)2* and Ph2Hg in tetrachloroethane at room temperature yields the monophenyl derivative NPCl2NSOClNSOPh. Treatment of NPCl2(NSOCl)2 with AgF2 in carbon tetrachloride leads to the formation of NPCl2(NSOF)2. From IR spectra it was determined that the phenyl and fluorine substituents are bonded to sulfur ring atoms.The IR and mass spectra of the two new compounds are discussed.
Preparation of some derivatives of meta‐di‐tert‐butylbenzene and tert‐butylbenzene
Authors: de Koning A.J. 
Published: September 2010

AbstractThe preparation of a number of mono‐brominated derivatives of meta‐di‐tert‐butylbenzene and tert‐butylbenzene from 3,5‐di‐tert‐butylacetanilide is described.
Alcohols as ligands: Part IV. Complexes of ethylene glycol with some metal(II) sulfates and nitrates
Authors: Knetsch D. , Groeneveld W.L. 
Published: September 2010

AbstractA number of complexes are reported of some metal(II) nitrates and sulfates containing ethylene glycol as the ligand. The general formula is M(EG)xAn, where M = Mn, Co, Ni, Cu, Zn, Mg, Ca and Cd; A = NOand SO; x = 1 ‐ 4; n = 1 ‐ 2.The compounds were characterized by means of physical measurements and chemical analyses.Ligand field parameters were calculated for the Co, Ni and Cu compounds, and the ligand is placed in the spectrochemical series.The infrared spectra indicate coordination of NOand SO. A considerable amount of hydrogen‐bonding is present in the complexes.In most of the compounds, the coordination of ethylene glycol is probably monodentate.
Conformational analysis of some (hydroxy)alkyl groups on benzene: Part II: The barriers to rotation of the hydroxyalkyl groups in 1,3,5‐tri(1‐hydroxy‐2,2‐dimethylpropyl)benzene and 1,3,5‐tri(1‐hydroxy‐1,2,2‐trimethylpropyl)benzene
Authors: Baas J.M.A. , Sinnema A. 
Published: September 2010

AbstractThe 100 MHz PMR spectra of the diastereoisomers of 1,3,5‐tri(1‐hydroxy‐2,2‐dimethylpropyl)benzene (2) and 1,3,5‐tri(1‐hydroxy‐1,2,2‐trimethylpropyl)‐benzene (1) are discussed. The high barrier to rotation reported in the literature for the hydroxyalkyl groups of 1 is probably in error. A value of 9.5 kcal/mole at −77° has been determined for 1‐(1‐hydroxy‐1,2,2‐trimethylpropyl)‐3,4,5‐trimethoxybenzene (3) and the low temperature spectra of 1 indicate a value in the same range. The barrier to rotation for the hydroxyalkyl groups in 2 or in the 3,4,5‐trimethoxybenzene derivative (4) could not be determined.
Reactivity of derivatives of 3‐bromo‐l, 5‐naphthyridine and 3‐bromoquinoline towards potassium amide in liquid ammonia
Authors: Pomorski J. , den Hertog H. J. , Buurman D. J. , Bakker N. H. 
Published: September 2010

AbstractReactions of some 2‐substituted derivatives of 3‐bromo‐l, 5‐naphthyridine and 3‐bromoquinoline with potassium amide in liquid ammonia were investigated. The course of these aminations is compared with that of corresponding processes studied previously.
Vilsmeier formylation of vinylcyclopropanes: 1. Formylation of thujopsene
Authors: Traas P. C. , Boelens H. 
Published: September 2010

AbstractThujopsene(1) can be formylated in the 3‐position in 80% yield by use of one equivalent of the Vilsmeier reagent. The resulting 3‐formylthujopsene(4) is useful for the synthesis of other 3‐substituted derivatives (CH2OH, COOH, COCH3). With an excess of the reagent higher formylation products are formed. Two such products have been isolated and characterized and a mechanism for their formation is put forward.
A spectroscopic study of zinc(II), cadmium(II) and mercury(II) complexes with tricyclohexylphosphine as ligand
Authors: Moers F. G. , Langhout J. P. 
Published: September 2010

AbstractThe preparations of the complexes M(PCy3)2X2 and M(PCy3)X2 with M = Zn, Cd or Hg, X = Cl, Br, I or SCN, PCy3 = tricyclohexylphosphine and some of their adducts with acetone, methanol or carbon disulfide are reported. Their infrared spectra in the range 4000‐200 cm−1 and their Raman spectra between 4000‐100 cm−1 have been investigated. From these data we conclude for the dimeric complexes M(PCy3)X2 with M = Cd or Hg and X = Cl, Br or I, a distorted tetrahedral coordination around mercury or cadmium. For the complex Hg(PCy3)(SCN)2 we suggest a trigonal coordination around mercury. Assignments are proposed for the metal‐halogen and metal‐phosphorus frequencies.
Thermal rearrangement of 2‐alkynyl alkanedithioates
Authors: Meijer J. , Vermeer P. , Bos H. J. T. , Brandsma L. 
Published: September 2010

Abstract2‐Alkynyl alkanedithioates R1R2CHC(S)‐S‐CH(R3)CCR4 (R1‐R4=H or alkyl) rearrange at 130‐140° in the presence of catalytic amounts of C2H5N(i‐C3H7)2 to 1,3‐dithiole derivatives (5) possibly via allenyl alkanedithioates R1R2CHC(S)SC(R4)CCHR3 although these intermediates have not been isolated. Traces of acids can cause dimerisation of the 1,3‐dithioles.
The crystal and molecular structure of the p‐iodobenzoate of 23‐demethylgorgosterol
Authors: Hsu I‐Nan , van der Helm Dick 
Published: September 2010

AbstractThe crystal and molecular structure of a cyclopropane containing marine steroid, 23‐demethylgorgosterol, and its absolute configuration have been determined on the p‐iodobenzoate derivative. The compound crystallizes in the space group P21212,1 with cell dimensions a = 14.076, b = 39.15 and c = 5.987 Å. There are four formula units (C36 H51 O2 I) per unit cell. The structure was determined and refined using 1872 counter data. The final R‐value is 7.4%. The structure determination confirms the presence of a cyclopropane ring in the side chain. An explanation is given for the two additonal highfield protons observed in the NMR spectrum.
Photodecomposition of some carboxylic acids and the properties of the radicals formed
Authors: van Beek H. C. A. , Heertjes P. M. , Schaafsma K. 
Published: September 2010

AbstractIrradiation of dl‐mandelic, phenylacetic, formic, malonic or dl‐tartaric acid in aqueous or ethanolic solutions with U. V. light results in the photodecomposition of these acids into ·COOH and the respective residual radicals. The ·COOH radical has strong reducing properties and can reduce azo dyes, if they are added to the solution prior to irradiation, to amines. The residual radicals formed together with ·COOH upon photodecomposition of the carboxylic acids, can cause fading of the dyes either by reduction or by addition to the chromophoric system.