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Der Dimethylester des aus denaturiertem C-Phycocyanin, einem in den Blaualgen (Cyanophytae) enthaltenen Chromoproteid, mit siedendem Methanol isolierten blauen Farbstoffes ist erstmalig totalsynthetisch dargestellt worden. Die Schlusselreaktion bei der durchgefuhrten Synthese besteht in der Kondensation von (E)-2-Athyliden-3-methyl-1-thiosuccinimid (12b) mit dem 2-Brom-2-(2-pyrrolyl)essigsaure-benzylester-Derivat 18b unter Anwendung der von Eschenmoser und Mitarbeitern13) entwickelten Methode der “Schwefel-Kontraktion”. Die aus dem erhaltenen 5(1H)-Pyrromethenon 20b leicht zugangliche Carbonsaure 21 liefert durch Kondensation mit 5′-Formylisoneoxanthobilirubinsaure-methylester (22), dessen Darstellung gegenuber der Literaturvorschrift verbessert worden ist, das gewunschte Phycobiliverdin (racem. 1), dessen analytische sowie elektronen-, infrarot-, kernresonanz- und massenspektroskopische Daten mit denjenigen des Naturproduktes ubereinstimmen. – Das fur die Synthese benotigte Thiosuccinimid 12b wurde neben seinem Konstitutionsisomeren 12a durch Thiolyse des Lactimathergemisches, das bei der Umsetzung vom Silbersalz des (E)-2-Athyliden-3-methylsuccinimids (9) mit Athyljodid entsteht, erhalten und durch Chromatographie an Aluminiumoxid aus dem Reaktionsgemisch rein isoliert. Seine Konstitution lies sich 1H-NMR-spektroskopisch eindeutig nachweisen. Zur Bestatigung der getroffenen Konstitutionszuordnung wurden ferner die 1H-NMR-spektroskopischen Daten des auf regiospezifischem Wege dargestellten 2-Isopropyliden-3-methyl-1-thiosuccinimids (15) herangezogen. Letztgenannte Verbindung lies sich ebenfalls mit Hilfe der “Schwefel-Kontraktionsmethode” mit dem 2-Brom-2-(2-pyrrolyl)essigsaure-methylester-Derivat 18a zum 5(1H)- Pyrromethenon 20a kondensieren, dessen Reaktion mit 5′-Formylisoneoxanthobilirubinsaure-methylester zum Bilatrien 23 fuhrte. Durch schonende alkalische Hydrolyse des letzteren und anschliesende Behandlung mit Saure wurde in sehr geringer Ausbeute das “Homophycobiliverdin” 24 erhalten. Syntheses of Bile Pigments, IV1). – The Total Synthesis of Racemic Phycocyanobilin (Phycobiliverdin) and of a “Homophycobiliverdin” 2) The dimethyl ester of the so called “blue pigment”, which is isolated by refluxing denatured C-phycocyanin, a photosynthetically active chromoproteid from blue-green algae, in methanol, has been synthesized for the first time. The key reaction of the synthesis consists of the condensation of (E)-2-ethylidene-3-methyl-1-thiosuccinimide (12b) with the benzyl ester of the 2-bromo-2-(2-pyrrolyl)acetic acid derivative 18b using Eschenmoser's “sulfide contraction method”13). The readily accessible carboxylic acid 21 of the 5(1H)-pyrromethenone 20b obtained reacts with the methyl ester of 5′-formylisoneoxanthobilirubinic acid (22), for which an improved synthesis is given, to yield the desired phycobiliverdin (racem. 1). Electronic, IR, 1H-NMR and mass spectra as well as analytical data of the synthetic product agree with those of the natural material. – The thiosuccinimide 12b required for the synthesis was obtained, together with its isomer 12a, by thiolysis of the mixture of lactim ethers which are formed on reaction of the silver salt of (E)-2-ethylidene-3-methylsuccinimide (9) with ethyl iodide; it was finally isolated by chromatography on alumina. Its constitution was established on the basis of its 1H-NMR spectrum. Supporting evidence for this structure was afforded by comparison with the 1H-NMR data of 2-isopropylidene-3-methyl-1-thiosuccinimide (15), which was synthesized regiospecifically. The latter compound also reacts under the conditions of the “sulfide contraction method” with the methyl ester of the 2-bromo-2-(2-pyrrolyl)acetic acid derivative 18a. The 5(1H)-pyrromethenone 20a which is formed condenses with the methyl ester of 5′-formylisoneoxanthobilirubinic acid to yield the bilatriene 23. Careful hydrolysis of 23 in basic media and subsequent treatment with acid leads to the formation of “homophycobiliverdin” 24 in very low yield.

Anthracite, bituminous and subbituminous coal when treated with naphthalene anion in tetrahydrofuran added negative charges to form the corresponding coal anions. Alkylation of bituminous and subbituminous coal anion with ethyl iodide resulted in the addition of 16 and 14 ethyl groups per 100 carbon atoms. The alkylated coals were 88 and 45% soluble in benzene. The molecular weights of the benzene-soluble portions of the bituminous and subbituminous coal were respectively 2000 and 700. An attempt to add alkyl groups to anthracite anion was not successful.

A series of peaks in the Raman spectra of gaseous CH3CH3, CH3CH2Cl, CH3CH2Br, CH3CD2Br, CD3CH2Br, CD3CD2Br, CH3CH2I, CH3CD2I, and CD3CH2I have been observed and assigned to the torsional overtones, (Δν = 2) of the methyl group. From these spectroscopic data, barriers to internal rotation have been calculated for the ethyl halides. For the compounds where the barriers are accurately known from previous work, the values obtained in this study agree quite well. The value for the internal rotational barrier in ethyl iodide is 3.67 ± 0.01 kcal/mole, which is considerably higher than the value previously reported from microwave studies. It is shown that Raman spectroscopy can be a convenient technique for obtaining torsional barrier heights when one uses the Δν = 2 quantum jumps of the torsional motion.

Photoisomerization rates of dixanthylidenes and 10,10′-dimethyl biacridanes are enhanced up to thousand-fold by the external perturbers oxygen, alkyl halides, and also carbon disulphide, which is much more effective than ethyl iodide. Fluorescence quantum yields are lowered by these perturbers, and it is suggested that all of them act by enhancing the rates of intersystem crossing to the triplet state of the reactants, which then undergoes efficient isomerization.

Simple syntheses are described of two deuteriated tertiary amines, namely NN-dimethyl-p-nitro[α-2H2]benzylamine and tri([1-2H2]ethyl)amine. The deuteriation step in the preparation of the former amine involves a selective exchange of the benzyl protons in dimethylbis-(p-nitrobenzyl)ammonium bromide by treatment with alkaline deuterium oxide. The second preparation requires [1-2H2]ethyl iodide, which is converted into benzyltri([1-2H2]ethyl)ammonium iodide. The final, key step common to both syntheses is the debenzylation of the quaternary ammonium ion.

Some attempts to modify the quinoline-insoluble fraction (QI) of a petroleum pitch with the aim of increasing the yield of fusible matter which yields anisotropic needle coke on carbonization are reported. Alkylation with ethyl iodide and metallic potassium converted 60% of the QI into material soluble in benzene (BS) but this was infusible. In contrast Birch reduction yielded fusible chloroform-soluble material, but in a yield of only 15%. By combining both methods of modification, the yield of fusible matter reached 70%. The modification of unfractionated petroleum pitch by these reactions was also studied and it was found that the presence of quinoline-soluble material helped to increase the conversion of QI to fusible soluble matter to 80%. Catalytic hydrogenation of the alkylated QI was also tried, but resulted in thermal dealkylation, reconverting the alkylated QI to insoluble QI; on the other hand, the quinoline-soluble fraction was smoothly hydrogenated.

The wavelength for heavy atom enhanced phosphorescence is unambiguously established by time resolved excitation spectra in 50% EPA and 50% ethyl iodide at 77 K for protoporphyrin (795 nm), mesoporphyrin (773 nm), octaethylporphin (768 nm), and porphin (785 nm). Excitation spectra also establish the phosphorescence wavelength of brominated protoporphyrin in EPA at 77 K to be 783 nm, with a quantum yield φp ∼ 9 × 10−4. Using laser excitation the phosphorescence quantum yields in EPA were found for protoporphyrin (φp ∼ 5 × 10−5), mesoporphyrin (φp

6-MethyIpyridines substituted in the 3-position, which were quaternized with methyl or ethyl iodide, were condensed under Knoevenagel conditions with 3-indolealde- hyde or with 3-methyl-2-indolealdehyde. The indolylethenylpyridinium iodides thus produced were hydrogenated to the corresponding indolylethylpiperidines. Conversion of the hydrogenation products into acid salts or into quaternary salts provided compounds for pharmacological testing. Some of these are open-chain analogs of LSD.

The kinetics of the reaction between EtI and HI have been studied in the temperature range 263° to 303°C using a spectrophotometric technique for the determination of I2. The mechanism obeyed is the following: I2⇌2I, KI2I+EtI⇌ lim 21Et+I2,Et+HI⇌ lim 43EtH+I,, which has the rate law (neglecting Step 4): d(I2)dt=k1k3KI212(EtI)(HI)(I2)12k2(I2)+k3(HI).. Decomposition of EtI by unimolecular elimination of HI is negligible.A differential method was employed to determine the rate constants k1 and the ratio k2/k3. The Arrhenius parameters of these constants were evaluated experimentally and combined with known thermodynamic data to give the parameters of the individual constants k2, k3, k4. As with other I2 molecule systems, the A factors of Reactions (1) and (4) are high, being approximately equal to collision frequencies.With the assumption E2=0.2 kcal and the experimental activation energy E1, the C–I bond‐dissociation energy in EtI is found to be 52.9±1.0 kcal at 25°C. The heat of formation of the ethyl radi...

The exchange of iodine between ethyl and propyl iodides has been studied over Cu, Fe, Ni, Pd, Rh, and Ir powder catalysts in a flow reactor at temperatures less than 200 °C. The exchange between ethyl iodide and methyl, butyl, and isopropyl iodides was studied over Rh. Decomposition, accompanied by catalyst poisoning, occurred over metals having high heats of formation of the corresponding metal iodide such as Ni and Fe. The energy of activation for the exchange between ethyl and propyl iodides over various metals was in the range 11.6–12.7 kcal/mole. For ethyl iodide with other alkyl iodides over Rh the energy of activation increased slightly with the chain length from 11.2 to 14.4 kcal/mole. The rates suggest a Langmuir-Hinshelwood mechanism, but the heats of adsorption apparently decrease with increasing surface coverage. There is good correlation between relative exchange activity and both relative hydrogenation efficiency and d character of the catalysts.

The absorption spectra of the ethyl and higher halides have been examined in the region 2000–1000A. It has been found that they are essentially similar to those of the methyl halides. The ionization potentials of ethyl iodide are given as 9.30 and 9.88 volts and those of ethyl bromide as 10.24 and 10.56 volts. The ionization potentials of the higher halides cannot be determined exactly because of the presence of continuous absorption from the C–C and C–H bonds, and of the diffuseness of the bands themselves. However there is strong evidence that the ionization potentials of consecutive members of the homologous series diminish asymptotically to a limiting value, the diminution from methyl to ethyl being by far the greatest. A comparison of the way the ionization potentials diminish and the dipole moments of the carbon‐halogen bonds increase as we ascend the homologous series indicates a definite connection between the two phenomena.

An improved method of preparing deuterated alkanes from the halides has been developed. Dehalogenation of ethyl iodide, 1,1-dibromoethane, and 1,1,1-trichloroethane with zinc dust in deuterium oxide – dioxane solutions, or even with deuterium oxide alone, gave excellent yields of ethane-d1, ethane-1,1-d2, and ethane-1,1,1-d3. Methane-d1, -d2, -d3, and -d4 were prepared similarly from methyl iodide, dibromomethane, chloroform, and carbon tetrachloride respectively. The isotopic purity of the products was over 90 mol.%. The reaction is also applicable to higher alkyl halides.

The application of organoaluminium compounds as components of organometallic or complex systems is connected with a knowledge of their reactions with electron donors. Reactions with nitriles, ketones, esters, ethers, alkyl chlorides, vinyl chloride, and acid chlorides as the electron donors were investigated. The first stage of the reaction of an organoaluminium compound with an electron donor involves formation of the corresponding donor-acceptor complex. A knowledge of the structure of the formed complexes is very important for an elucidation of the reaction course and mechanism. The heat of formation, composition, and molecular weight of the corresponding complexes were determined, and their i.r. and n.m.r. spectra were studied. From these investigations general conclusions were made concerning, the influence of the Lewis acidity of the organoaluminium compound on the structure of its complexes and on their reactivity; the effect of reactant mole ratio (organoaluminium compound to electron donor) on the reaction course, and the influence of the molecular structure of the complex and of dislocation of electrons on the reaction mechanism. Hallwachs and Schafarik' synthesized the first organoaluminium compound 120 years ago. By treating aluminium with ethyl iodide they prepared ethylaluminium sesqui-iodide. However, the chemistry of organoaluminium compounds received little attention until the investigations of Ziegler and his collaborators, in about 1950. The development of the direct synthesis of organoaluminium compounds from aluminium, ethylene. and hydrogen, and elaboration of normal pressure polymerization of ethylene, aroused great interest. Almost simultaneously, numerous research centres over the world undertook research and technological investigations. Organoaluminium compounds proved to be of both theoretical and technological interest because of their ability to form auto and other complexes, their high reactivity, and associated structure and valence theory problems. In spite of the two decades that have passed since Ziegler's discoveries and the intensive studies that have been conducted throughout. the interest in the chemistry of organoaluminium compounds has not declined. This is mainly due to the use of organoaluminium compounds as constituents of complex catalyst systems. 509

The aluminum chloride catalyzed reaction between β-14C-ethyl iodide and benzene in 1,2,4-trichlorobenzene as solvent was studied under different conditions of temperature and reaction time. Yields of ethylbenzene were estimated by isotopic dilution. Up to 20% rearranged product, α-14C-ethylbenzene, was found. The trend indicated that yield of ethylbenzene was lower and side chain rearrangement greater when the reaction mixture was heated at higher temperature for longer time. The rearrangement apparently occurred after the initial formation of β-14C-ethylbenzene. After a reaction time of 5 min at 154 °C, only 0.1–0.3% unreacted and unrearranged β-14C-ethyl iodide was recovered while the ethylbenzene obtained from the reaction showed about 2% rearrangement. When β-14C-ethylbenzene was heated with aluminum chloride in 1,2,4-trichlorobenzene for 2 or 24 h, rearrangement to α-14C-ethylbenzene was observed. In some experiments, a fragmentation product, toluene, was isolated. Its specific activity suggested that 1 mole of active ethylbenzene gave 2 moles of toluene only one of which was active. The mechanistic implications of these findings are discussed.

A number of very reactive radicals and atoms prepared by photolysis in rigid hydrocarbon glasses at the temperature of liquid nitrogen have been detected by their absorption spectra. Thus ethyl iodide dissociates to iodine atoms which only recombine to give I 2 when the glass is softened. Similarly CS 2 and ClO 2 give CS and CIO which can be detected spectroscopically in the frozen glass. Toluene and other benzyl derivatives yield the benzyl radical, and the spectra of a number of similar unstable aromatic radicals have been recorded for the first time. Most of these radicals have lifetimes of less than 1 ms at comparable concentrations in the gas phase or in ordinary solutions, but have been observed for many hours in the rigid glass. The method should be of general applicability for the study of the primary products of photochemical or radiation chemical processes.

1. An investigation was made of the Arbuzov rearrangement of tris-2-chloroethyl phosphite under the action of methyl iodide, ethyl iodide, and acetyl chloride. 2. Some previously undescribed 2-chloroethyl esters of phosphorous acid and methyl-, ethyl-, and acetyl-phosphonic acids were synthesized.

In a previous publication it was shown that pressure was capable of exerting a considerable influence on the rate of reactions in solution. Two reactions were studied; the first, the interaction of sodium ethoxide and ethyl iodide in alcohol solution, was a typical example of the “normal” class, in which the number of molecules reacting is approximately equal to the number of collisions with the requisite activation energy, while the second, the interaction of pyridine and ethyl iodide in acetone solution, was a typical “slow" reaction, in which the number o f molecules reacting is several powers of 10 less than the number of collisions with the requisite activation energy. The rates of both reactions were increased by pressure, but while the first was accelerated 1.6 times at 3000 kg/cm 2 , the second was accelerated 7.2 times at 3000 kg/cm 2 , and much more at higher pressures. It seemed desirable to investigate other reactions falling into these two classes, to see whether this behaviour was general. With this end in view, the hydrolysis of sodium monochloracetate by aqueous caustic soda, another typical “normal” reaction, has been studied up to 12,000 kg/cm 2 , and the work on the sodium ethoxide and ethyl iodide reaction has also been extended to this pressure.

By treatment with diethylzinc and iodoform, benzene gave 7-ethylcyclohepta-1,3,5-triene in a yield of 58%, along with a quantitative formation of ethyl iodide. Alkylbenzenes, including methyl-, ethyl-, isopropyl-, tert-butyl-, and o-dimethylbenzene, gave the corresponding alkyl-substituted 7-ethylcyclohepta-1,3,5-trienes in yields of 60, 45, 41, 35, and 52% respectively. The tropylium iodide resulting from the adduct of the iodocarbenoid of zinc to benzene (7-iodonorcaradiene) is suggested as an intermediate in the formation of the 7-ethylcycloheptatriene.

Reaction of 3, 6-dimethoxy-4-nitropyridazine 1-oxide (I) with alkyl halides were investigated, and following results were obtained. 1) Reaction with methyl iodide gave 1, 3, 4-trimethoxy-6 (1H) pyridazinone (II). 2) Reaction with ethyl iodide gave 1, 4-diethoxy-3-methoxy-6 (1H) pyridazinone (IV). 3) Reaction with ethyl chlorocarbonate gave 1-ethoxycarbonyloxy-3-methoxy-4-chloro-(VI) and 1, 4-bisethoxycarbonyloxy-3-methoxy-6 (1H) pyridazinone (VII). 4) Reaction with ethyl bromoacetate gave 1, 4-bisethoxycarbonylmethoxy-3-methoxy-6 (1H) pyridazinone (IX). Moreover the reaction of 4-nitropyridazine 1-oxide derivatives with methyl iodide was described. 1) Reaction with 3-methoxy-4-nitro-6-methylpyridazine 1-oxide (XIII) gave 3, 4-dimethoxy-6-cyanopyridazine 1-oxide (XV) and 1-methyl-3-methoxy-6-cyano-4 (1H) pyridazinone (XVI). 2) Reaction with 6-methoxy-4-nitropyridazine 1-oxide (XIV) gave 1, 4-dimethoxy-6 (1H) pyridazinone (XX).

The addition of HI to C2H4 yields C2H5I at low temperatures and C2H6+I2 at higher temperatures. From 289° to 331°C the rate law is mixed—second order with C2H6+I2 as products. The rate is independent of added I2 and has a specific rate constant k2 (units, liter/mole‐sec): logk2=8.52−(28900/4.575T). The pyrolysis of C2H5I from 330° to 392°C goes by a first‐order process to C2H4+C2H6+I2. The first‐order rate constant is given by (units, sec—1): logku=13.66−(50000/4.575T).If it is assumed that both processes have the same rate determining step, namely the reversible dissociation of C2H5I, they yield an equilibrium constant in good agreement with independently calculated values of Keq for this dissociation. Under these conditions k1, the specific rate constant for the unimolecular split of C2H5I into C2H4+HI is given by ku/2. Arguments are presented to show that this common path involves the four‐center molecular transition state rather than a radical disproportionation. The latter, however, may account for as much as 20% of the pyrolysis at 392°C.

Benzene, naphthalene, related hydrocarbons and some of their derivatives act as optical sensitizers towards the decomposition of alkyl iodides in hexane solution. Within this group, the sensitizing power of a substance towards an acceptor runs parallel with the ability of the acceptor to quench the fluorescence of the sensitizer; this is demonstrated quantitatively and in detail. The quantum yield of the naphthalene‐sensitized decomposition of ethyl iodide follows an equation of the form 1/φ=a+b(1/[EtI]), and detailed analysis of the quenching and sensitization shows that while sensitization and fluorescence are alternative processes, they are not completely reciprocal, in that more molecules may sensitize than may potentially fluoresce. All of the observed features of the sensitization are consistent with its being the result of a resonative transfer of energy at collision from the excited sensitizer to the acceptor.

A radiofrequency mass spectrometer has been used, with slight modification, to measure the kinetic energy of fragment ions from polyatomic molecules. Selected ions from CO 2 , CH 3 OH, C 2 H 5 OH, C 3 H 7 OH, i-C 3 H 7 OH, CH 3 I and C 2 H 5 I were examined for excess kinetic energy by means of retarding potential analysis before mass analysis. The excess kinetic energy for any given ion was always greater for 70 V electron impacts than for 50 V. Such ions as m/g 31 and 29 from ethanol have an excess of about 0·45 V kinetic energy for 50 and 70 V electrons; m/q 29 and 27 from isopropanol also have about 0·45 excess energy for 70 V electrons; CH + 3 ions from the alcohols and from the iodides showed excess kinetic energy while m/q 27 from ethyl iodide had 0·9 V excess energy for 70 V electrons. The results are interpreted as evidence of a significant num ber of dissociations from electronic states which are not in effective competition with one another. The existence of non ­ competing dissociation paths for a given molecular ion complex would preclude the application of the statistical theory of mass spectra to predict the breakdown scheme of that complex.

The incorporation of halogen endgroups in polymers has been established in the following cases for polymerization of styrene, methyl methacrylate and methyl acrylate: (1) chain transfer with halogenated hydrocarbons (chloroform, benzyl chloride, bromoform, ethylene dibromide, octadecyl bromide, ethyl iodide, cetyl iodide); (2) copolymerization with suitable components (vinyl bromide, tetrachloroethylene, trichloroethylene); (3) use of halogen atoms as initiators, e.g. FeCl 3 (+h v ), FeBr 3 (+h v ), HCl(+h v ) and KBr+H 2 O 2 (+h v ); (4) chemical transformation of a group already present in a polymer, e.g., conversion of hydroxyl endgroup to halogen endgroup by a usual method; addition of hydrogen bromide to double bond in polymers. The method of detection consists in converting a polymer with halogen endgroups to a quaternary pyridinium halide by refluxing with pyridine, a few drops of glycerol being added in the case of chlorine endgroup to facilitate the reaction. The converted quaternary halogen endgroup is detected independently by two tests developed in this laboratory: the dyeinteraction test with rhodamine 6GX conc. (Calco) dye and also the dye-partition test for cationic group with Bromophenol Blue or Disulfine Blue VN 150 as reagents.

This paper summarizes some of the data in the literature on the effects of phase on chemical reactions induced in organic systems by light, ionizing radiation and nuclear transformations. It also presents new data which show that: (1) the ratio of HI to I/sub 2/ produced in the radiolysis of pure isopropyl iodide with Co/sup 60/ gamma -rays is about tenfold higher in the solid phase at --190 deg than in the liquid at room temperature; (2) the yield of iodine from the radiolysis of isopropyl iodide in either the liquid or solid is dependent on the past history of irradiation of the sample in the other phase; (3) when the spectrum of ethyl iodide glass at --190 deg is examined after exposure of the solid to 2537 A. light, little or no change is observed as a result of the irradiation, but when the glass is then melted amd immediately refrozen, an absorption peak appears at 3700 A.; a similar effect is caused by the self-irradiation of tritiated ethyl iodide glass; (4) the ratio of HI to I/ sub 2/ produced by the photolysis of ethyl iodide is approximately ten-fold higher in the glass at --190 deg than inmore » the liquid at room temperature. (auth)« less

1. The velocity of decomposition of sulphur iodide in carbon tetrachloride solution has been studied at 0° and at 30°C. At 30°, the velocity of decomposition is about four times that at 0°C. 2. With sulphur iodide solutions, a complete absorption for all wavelengths below 4770 A is noticed. Data on the instability of sulphur iodide obtained by analytical methods, are confirmed by the spectroscopic investigations.

The alkaloid delsoline (C25H41O7N) was oxidized by acid permanganate mostly to dehydrooxodelsoline, and by neutral permanganate to anhydrohydroxydelsoline. Oxidation of the alkaloid with mercuric acetate produced anhydrohydroxy-N-de-ethyldelsoline which could be re-ethylated with ethyl iodide, thus showing the presence of an N-ethyl group in delsoline. Anhydrohydroxydelsoline was also obtained from O-acetyldelsoline perchlorate by oxidation to an anhydronium salt followed by hydrolysis with sodium hydroxide, and this method of preparation provides evidence of its carbinolamine structure. O-Acetyloxodelsoline, obtained from acetyldelsoline, is cleaved by lead tetra-acetate to a secodiketone that loses the elements of methanol on recrystallization. Hence the base contains two vicinal tertiary hydroxyls, one of which is β to a methoxyl group. Dehydrooxodelsoline is also cleaved by lead tetra-acetate and the product undergoes an internal aldol rearrangement. These results are interpreted in the light of a structure that is tentatively suggested for delsoline.

Treatment of 9-alkyladenines (Ia, b, c) with 30% aqueous hydrogen peroxide in acetic acid at 30° produced the corresponding 9-alkyladenine 1-oxides (II a, b, c) in 51-71% yield. The 1-N-oxides were found to undergo alkylation almost exclusively at the oxygen atoms of the N-oxide groups when treated separately with methyl iodide, ethyl iodide, and benzyl bromide in N, N-dimethylacetamide at room temperature, and the corresponding salts (III) of all the nine possible 1-alkoxy-9-alkyladenines were obtained in excellent yields. 1-Ethoxyadenosine hydriodide and 1-benzyloxyadenosine perchlorate were also prepared from adenosine 1-oxide (II d) in a similar way. The ultraviolet and nuclear magnetic resonance spectral data on the 1-alkoxyadenine derivatives obtained in the previous and present studies are collected in Tables II and III.

In [1], on the example of the telomerization of ethylene with ethyl iodide, we developed a method for determining chain transfer constants taking account of the gradual reaction of the telomers and reversibility of the chain transfer reaction. In the present investigation this procedure was used to study the influence of the telogen structure, and of temperature, in telomerization with ethylene on the chain transfer constants.

In ethanolic solution methyl iodide reduces on tin cathodes to tetramethyltin but ethyl halides do not yield the corresponding tin ethyls except in insignificant yields. Increases in alkyl halide concentrations improve the yields of tin alkyls and also increase the passivation of the surface towards the reduction. The distribution of gaseous products from ethyl iodide reduction indicates the formation of small concentrations of free ethyl radicals at less negative potentials. Electrodes directly immersed in the catholyte are inactive and require cathodic polarisation in the background medium to improve activity.

Previous work has shown that pressure has an accelerating effect on a large number of chemical reactions in the liquid phase. The rates of the reaction between pyridine and cetyl halides have been studied at different temperatures and pressures, but it was not found possible to interpret the results by means of the ordinary reaction velocity equations, and no conclusions could be drawn as to the mechanism of the pressure effect. In making a further attempt to determine this mechanism, it seemed desirable to take reactions which have already been studied at atmospheric pressure and are known to follow the simple velocity equations, and to investigate the effect of pressure on the velocity con­stants. The effect of temperature on the velocity constant of a reaction k , can be expressed by the Arrhenius expression k = A e -E/RT . A knowledge of the variation of the velocity constant with pressure at different temperatures would show whether this change is due to a change in the value of the constants A or E, or of both.

The existence of the isomer 130Im (9.2 min) has been established by the growth of the gamma‐ray spectrum of the 130I ground state following neutron irradiation of 129I, and also by the incorporation of 130I into organic combination as a result of the isomeric transition of I2(130Im) dissolved in n‐hexane. The isomer decays to the ground state by a highly converted isomeric transition with a 0.77 probability and to the 0.54‐MeV level of 130Xe by beta emission with 0.23 probability. The cross‐section ratio, σ(130Im)/σ(130I), for production of the isomers from 129I by pile neutrons is about 2.0. The fraction of the isomeric transition events which result in organic incorporation of the 130I daughter in solutions of I2(130Im) in n‐hexane, or in solutions of RI(130Im) in ethyl iodide, is about 0.40.

It is shown, that organic molecules for which a strong donor-acceptor interaction with aluminium triiodide can be expected, with formation of a molecular complex, cause a strong “exchange blocking” effect in the AlI3C2H5I liquid system. Independently of the amount of the added foreign compound, however, a significant part (about 20–30 per cent) of the radioiodine atoms primarily present in the metal iodide is transferred to the ethyl iodide in the first rapid period of the exchange. The suggest a significant role for intermediate compounds and/or solid-liquid surface exchange. Aromatic hydrocarbons and olefines which are supposed to form π-complexes with aluminium trihalides, cause no effect on the iodine exchange in the system investigated.

The radical yields of C2H5• and CCl3• observed by electron spin resonance of CCl4 + C2H5I mixtures irradiated by γ rays at 77°K are compared with yields of HCl, I2, and HI measured after thawing. The dissociative capture of thermalized electrons by CCl4 is extremely effective and accounts for most of the observed radicals. The difference between yields of HCl and CCl3• results from charge transfer from C2H5I+ to CCl3•. The formation of iodine proceeds both from neutralization processes of Cl− ions with positive ions formed from C2H5I, and from ion–molecule reactions.

Bis(diathylamino)-diorgano-biphosphine, (C2H5)2N(R)P-P(R)N(C2H5)2, werden mit Athyljodid bzw. Chlorwasserstoff in Ather umgesetzt. Die Athyljodid-Einwirkung fuhrt uber die Spaltung der PP-Bindung und Quarternisierung zu Diathylamino-organo-jod-phosphinen und Diathylamino-diathyl-organo-phosphoniumjodiden, wahrend die Umsetzung mit Chlorwasserstoff je nach den angewandten Mol-Verhaltnissen auser Cyclo-polyphosphinen Diathylamino-organo-chlor-phosphine und Organo-dichlor-phosphine liefert. Dabei wird ein unterschiedliches Verhalten des Bis(diathylamino)-diathyl-biphosphins gegenuber dem Bis(diathylamino)-dicyclohexyl- und Bis(diathylamino)-diphenyl-biphosphin festgestellt. The PP bonds in bis(diethylamino)-diorganyl-biphosphines, (C2H5)2N(R)PP(R) · N(C2H5)2, are cleaved by ethyl iodide or hydrogen chloride in ether. Ethyl iodide yields phosphine iodides and phosphonium iodides, whereas in the case of HCl, according to the experimental molar ratio biphosphine: HCl, phosphine chlorides or dichlorides are formed in addition to cyclo-polyphosphines. That biphosphine with R = ethyl exhibits a different reaction behaviour compared with those of the biphosphines having R = cyclohexyl or R = phenyl.

The organic retentions for (d,p), (n,2n), and (γ,n) activation of iodine in liquid methyl and ethyl iodide, containing added iodine, have been found to be equal to the retentions observed in radiative neutron capture. This demonstrates that the chemical effects are independent of the recoil energy of the activated nucleus, of the mode of nuclear formation, and of variation of fragmentation effects within the recoil track. In the absence of scavenger iodine, the increase in retention due to radiation damage is less than 10 percent in all cases studied.

The kinetics of the ethyl iodide–silver nitrate reaction in 0·02M-aqueous potassium nitrate solution at 5° were studied in the presence of charcoal and of silver iodide. The rates depended on the concentration of each substrate either raised to a fractional power, as in a Freundlich adsorption isotherm, or arranged in a form analogous to a Langmuir isotherm, and thus indicated a Langmuir–Hinshelwood mechanism. When the difference in surface areas was taken into account, silver iodide was found to be a more effective catalyst than charcoal by a factor of at least 40. The activation energies were 20 kcal. for the homogeneous reaction, 10.4 kcal. for the charcoal-catalysed process, and 8.5 kcal. for the reaction on the silver iodide surface.