Methode zur Konstitutionsaufklärung der Reaktionsprodukte der Umsetzung von Cellulose mit Formaldehyd. 18. Mitteilung über textilchemische Untersuchungen [1]

(1) A method is described which allows the elucidation of the structure of cotton cross-linked with formaldehyde. It consists of a permethylation process (5 methylations with dimethyl sulphate and sodium hydroxide in dimethyl sulphoxide, followed by two exchange methylations of the formalised sodium cellulosate with methyl iodide in n-butanol), hydrolysis of the product in 72% sulphuric acid to the respective methylated glucoses, reduction of the mixture of glucoses to the respective sorbitols, blocking of all free hydroxyl groups by acetylation, trifluoroacetylation or formation of trimethylsilyl ethers, and vapour phase chromatographic separation of the derivatives. (2) It is shown that after permethylation practically no free hydroxyl groups can be detected and that scarcely any replacement of methylene or oxymethylene cross-links by methyl groups has taken place. With the exception of losses in filtration of the permethylation product, all stages of the process proceed on an almost quantitative basis.     

Über die chemische Konstitution der mit Divinylsulfon vernetzten Cellulose. 12. Mitteilung über textilchemische Untersuchungen

Cotton and viscose fibres treated with divinyl sulphone under alkaline conditions were degraded in sulphuric acid. By column chromatography degradation products have been identified which contain two glucose units on mono- and dimeric sulphone derivatives, i.e. glucose ethers of 2,2′-dihydroxyethylsulphone and of 2,2′-bis-(hydroxyethylsulphonyl)-diethylether. This is the first direct chemical proof of the existence of cross-linkages in cellulose treated with bifunctional reagents.     

Notiz über eine regiospezifische Methode zur Herstellung von konjugierten Cyclohexadienen Über synthetische Methoden, 11. Mitteilung

β,γ-unsaturated δ-hydroxy-cyclohexene carboxylic acids undergo a smooth decarboxylative elimination when treated with DMF-dineopentylacetal in an unpolar solvent. The reaction provides a method for the regiospecific preparation of 1,3-cyclohexadiene derivatives under non-isomerizing conditions, starting from easily accessible and structurally variable intermediates.     

Selbstorganisation von Chinodimethanen über kovalente Bindungen,Mitteilung III,Untersuchungen zur Herstellung von Nanostrukturen

Self‐Assembly of Quinodimethanes through Covalent Bonds. Part III. Investigations on the Preparation of Nanostructures As part of our studies on the tetramerization of quinodimethane 1 to the macrocyclic compound 2 , the influence of substituents on this reaction was investigated. It was found that a large range of substituents such as 2‐phenylethyl, 2‐(4‐methoxyphenyl)ethyl, 2‐(4‐fluorophenyl)ethyl, 2‐[4‐(tert‐butyl)phenyl]ethyl, and 2‐[4‐(2‐phenylethyl)phenyl]ethyl, attached at positions 2 and 7 of 9H‐fluorene, do not prevent the tetramerization. The key step in the formation of the macrocylic compounds 13a – e is the debromination of 12a – e with mercury to the corresponding quinodimethanes which undergo a self‐assembly forming 13a – e in high yields. To study the conjugative influence of substituents on tetramerization, the effect of the hex‐1‐ynyl groups at positions 3 and 6 of the 9H‐fluorene rings was investigated. In this case, the corresponding macrocycle 17 was generated by the reaction of diol 16a with SnCl₂. Although the expected tetramerization to 17 occurred, the yield was lower than in the case of 13a – e , due to the sensitivity of the product.     

Beitrag zur massenspektrometrischen retro-Diels-Alder-Reaktion: 1,2,3,4-Tetrahydrophenanthren. 35. Mitteilung über massenspektrometrische Untersuchungen

Contribution to the Mass Spectral retro-Diels-Alder Reaction: 1,2,3,4-Tetrahydrophenanthrene [1,4-¹³C]-1,2,3,4-Tetrahydrophenanthrene (1) was synthesized starting from [1,4-¹³C]-succinic acid. The mass spectral behavior (EI./MS., 70eV) of 1 is very similar to that of tetraline [2] concerning its loss of ethylene from the molecular ion. Similarly the fragmentation reaction of the synthetic precursors, ketones 7 and 8 , seems to partly undergo a carbon rearrangement reaction prior to the elimination of ethylene which is unlike to the behavior of α-tetralone.     

Beitrag zur Massenspektrometrie substituierter α, ω-Alkandiamine. 29. Mitteilung über massenspektrometrische Untersuchungen

Contribution to the mass spectrometry of substituted α,ω-alkane diamines The main mass spectral fragmentation pattern of compounds of types 1 to 4 is discussed. After loss of C₆H₅ · CH₂ · from the molecular ion the acid correspondin to the N,N-disubstituted residue is splitted off. The mechanism of this fragmentation reaction depends on the member of CH₂-groups between the two nitrogen atoms (Schemes 1 and 3) and on the substitution pattern of both nitrogens (Scheme 2).     

Zur Berechnung der Aciditätskonstante von Sorbit aus der Sorbitolysenkinetik von Reaktivfarbstoffen. 4. Mitteilung über reaktionsmechanistische Untersuchungen an Reaktivfarbstoffen

The first acid dissociation constant of sorbitol is redetermined (PK_a = 13.00; 60°).     

Zur Photochemie von Allylaryläthern. 55. Mitteilung über Photoreaktionen

The photochemical reactions of different allyl aryl ethers (Scheme 3) were investigated in hydrocarbons (Chap. 3.1) and in alcoholic solvents (Chap. 3.2). The composition of the photoproducts depended very much on the nature of the solvent. Irradiation (3–95 h) of different methyl substituted allyl aryl ethers ( 1, 3, 5, 7 and 11 ) with a low pressure mercury lamp (λ_Emiss. = 254 nm; 6 or 15 Watt) under argon (quartz vessel) resulted in the formation of 2-, 3– and 4-substituted phenols, dienones and products of consecutive reactions (Tables 1–4 and 6). The results suggested that all products were formed by homolytic cleavage of the C? O bond in the singlet state of the ethers to intermediate radical-geminates (Scheme 5) followed by radical recombination of the two fragments. No products were formed by concerted processes (Table 5, Schemes 5 and 6). Upon irradiation of allyl aryl ethers lacking alkyl substituents at position 4 ( 1 and 5 ) in protic solvents, mainly 2- and 4-allylated phenols were obtained (Tables 1 and 4); 3-allylated phenols were formed only in small amounts (0.02%). However, in aromatic hydrocarbons or cyclohexane 3-allylated phenols were obtained from 1 , 5 and 11 in significant amounts (3–11%; Tables 1, 4 and 6). E.g., upon irradiation of allyl-2,6-dimethyl-2,4-cyclohexadien-1-one ( 6 ) besides 3- and 4-allyl-2, 6-dimethyl-phenol ( 23 and 24 ). Irradiation of 5 in methanol afforded 23 and 6 only in traces, whereas 24 was the main product.     

Stoffwechselprodukte von Mikroorganismen. 202. Mitteilung. Strukturaufklärung von Elaiophylin: Spektroskopische Untersuchungen und Abbau

Structure Elucidation of Elaiophylin: Spectroscopy and Chemical Degradation The structure of the antibiotic elaiophylin (azalomycin B) was elucidated by extended spectroscopic investigations and chemical degradation. Elaiophylin ( 26 ) is a macrodiolide with a 16membered dilactone ring. The synthesis of 7-acetoxy-6-ethyl-3-octanone ( 14 ), the acetyl derivative of an important degradation product, is described.     

Über die rolle der Aminogruppen der Faser für die Sorption von anionischen farbstoffen: Versuche mit Amino- und Hydroxypolypropylen 15. Mitteilung über textilchemische Untersuchungen [1]

(1) Three anionic mono azo dyes (Orange I, Orange II and Orange 8) and a 1:2 metal complex dye (Cibalan Grey BL) are dyed onto aminopolypropylene. With all the dyes, a Langmuir isotherm with a stoichiometric relation between the dye adsorbed and the concentration of amino groups on the substrate is obtained.     

Synthese von racemischen,isomeren Desoxo-4, 14-didemethyl-cassain-Derivaten. 4. Mitteilung über Cassain-Analoga

For the synthesis of demethyl analogues of Erythrophleum alkaloids, the tricyclic ketone 14 (trans-anti-trans) was prepared. The Horner reaction on 14 led to a mixture of cis/trans compounds, which could be separated into the homogeneous racemic isomers 21 and 22 . These compounds were transformed into the corresponding 2-dimethylamino-ethyl esters of their 3-dehydro and 3-O-carbamoyl derivatives.     

Reaktionen von Glutaminsäuredimethylester im Massenspektrometer. 21. Mitteilung über das massenspektrometrische Verhalten von Stickstoffverbindungen

The mass spectral fragmentation of dimethyl glutamate ( 1 ) and its deuterated derivatives 1a , 1b and 1c has been investigated. By loss of a methoxycarbonyl group from the molecular ion an ion of m/e 116 is generated. The latter splits off methanol (m*), the resulting fragment of m/e 84 giving raise to the base peak of the spectrum. Only part of the hydrogen transferred to the leaving group originates from thc amino group, as was suggested earlier [2] [3]. Basing on experiments with deuterated compounds we propose an additional mechanism for the reaction, i.e. hydrogen transfer from C(3) to methoxyl. The fragment generated by both processes is most likely to be a pyrrolinonium ion. Thermal side reactions in the mass spectrometer (formation of pyroglutamic acid ester) followed by fragmentation may lead to the same ion. – The mechanisms discussed are supported by the mass spectral fragmentation of N-acetyl-glutamic acid diesters 3 , 3a , 3b and 3d and of the N, N-dimethyl derivatives 4 and 4a . – The fragmentation reactions investigated are similar to some of 1,3-trimethylenediamine derivatives [7]. This means that there are parallels in the mass spectral fragmentation of difunctional compounds irrespective of the nature of the functional groups.     

Über Chalkogenolate. LXIV. Untersuchungen über Thiomeisensäuren 7. Kristallstruktur von Tetraäthylammoniumcyandithioformiat

On Chalkogenolates. LXIV. Studies on Thioformic Acids. 7. Crystal Structure of Tetraethylammonium Cyanidithioformate Tetraethylammonium cyandithioformate [(C₂H₅)₄N][NCCS₂] crystallizes in the orthorhombic space group Pbem? D (no. 57): a = 7.715; b = 13.945; c = 12.255 Å and Z = 4. Planar cyandithioformate ions are packed parallel the xy plane at z = 0.25 and 0.75. The nitrogen atoms of the ammonium groups build columns along the glide plane c. Structural refinements were completed to a weighted R = 0.078.     

Zur Regioselektivität von Cycloadditionen photochemisch erzeugter Benzonitril-isopropylide. 51. Mitteilung über Photoreaktionen

On the regioselectivity of cycloaddition reactions of photochemically generated benzonitrile-isopropylides This paper deals with the physical and chemical differences of zwitterionic benzo-nitrile-isopropylides, which differ by a p-substituent in the phenyl ring (H, F, OCH₃; Scheme 2). These dipolar species (4–6) are produced by irradiation of the corresponding 2 H-azirines ( 1–3 ; Scheme 1) in a 2-methylpentane glass at ?185°. Their UV. spectra are reproduced in the Figure. The spectra of 4 and 5 are characterized by an ‘aromatic band’ at short wavelength, and a longer wavelength band at approximately 275 nm, which is considered to be characteristic of the nitrile-ylide system. The UV. spectrum of the methoxy derivative 6 , which shows a broad absorption at 260 nm, arises by an addition of the ‘nitrile-ylide band’ and the anisole band. The three dipolar species 4–6 do not show any significant differences in the regioselectivity of the cycloaddition with methyl α-methacrylate even though F and OCH₃ have quite different σ-constants (Scheme 1). The addition according to modus A is very much preferred (B/A = 0,076). – It seems, that the substituents F and OCH₃ do not affect the physical and chemical behaviour of the parent benzonitrile-isopropylide (4) . All three dipolar species 4–6 react regiospecifically according to modus A with methyl trifluoroacetate (Scheme 1). The regioselectivity is reduced in the cycloaddition of 4 with methyl propiolate and ethyl phenylpropiolate (B/A = 0,04 and 0,28, respectively). The reduced regioselectivity in the latter case may be attributed to a reduced polarity of the triple bond in the dipolarophile.     

Hydrolyse und Alkoholyse von Reaktivfarbstoffen: II. Hydrolyse von Monochlortriazin-Farbstoffen. 2. Mitteilung über reaktionsmechanistische Untersuchungen an Reaktivfarbstoffen

• 1 The kinetics of the hydrolysis of three monochlorotriazine reactive dyes have been determined in alkaline buffer solutions at 60°, 80° and 98° (ionic strength I = 0.0625).
• 2 The kinetic results as well as diffusion measurements in aqueous solution indicated that these dyes form aggregates at dye concentrations at 6 · 10^?4, but practically not at 6·10^?6 moles/l.
• 3 The reaction order with respect to hydroxyl ions has been determined. The influence of general base concentration was negligible.