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New aromatic polyamide-imides (PAI) containing various alkyl substituents were prepared by the substitution reaction of Torlon® 4203L (commercialized PAI resin) with the corresponding alkyl halides such as methyl iodide, ethyl iodide, and n-butyl bromide. The resulting amorphous PAIs with glass transition temperatures ranging from 238 to 276°C had inherent viscosities in the range of 51 to 53 mL/g. These polymers were readily soluble in aprotic polar solvents such as N-methylpyrrolidone, dimethylformamide, dimethyl acetamide, etc. Furthermore, the incorporation of various alkyl substituents into amide groups of the PAI resin increased the melt processability, but slightly decreased the thermal properties compared with conventional PAI resin. The melt viscosities of resulting PAIs determined at 330°C under the frequency of 10-1 rad/sec were in the range of 103–105 Pa.s. On the other hand, the modified PAIs showed significantly lower melt viscosities than Torlon® 4203L, which was almost comparable to the conventional polyetherimide, Ultem-1000. Neue aromatische Polyamidimide (PAI) wurden durch Reaktion von Torlon® 4203L (ein handelsubliches PAI) mit verschiedenen Halogenalkanen (Methyliodid, Ethyliodid, n-Butylbromid) hergestellt. Die Glastemperaturen dieser amorphen PAI liegen zwischen 238 und 276°C, die Grenzviskositaten betragen 51 bis 53 mL/g. Die PAI sind leicht loslich in polaren, aprotischen Losungsmitteln wie z.B. N-Methylpyrrolidon, Dimethylformamid, Dimethylacetamid u.a. Der Einbau der Alkylsubstituenten in die Amidgruppen der PAI verbesserte die Verarbeitbarkeit aus der Schmelze, verringerte allerdings die thermischen Eigenschaften im Vergleich zu einem konventionellen PAI. Die bei 330°C und einer Frequenz von 0,1 rad/s gemessenen Schmelzviskositaten der hergestellten PAI betragen 103–105 Pa.s. Andererseits sind die Schmelzviskositaten der modifizierten PAI geringer als die von Torlon® 4203L, das mit dem konventionellen Polyetherimid Ultem-1000 vergleichbar ist.

The preparation of (all Z)-1,17-dichloro-4,7,10,13-heptadecatetraene is reported. The synthesis was performed in five steps with a total yield of 22 %, starting from 5-chloro-1-pentyne. The corresponding bis Grignard reagent was used in a copper-mediated coupling reaction with [1-11C]ethyl iodide followed by a carbonation with CO2 to afford [19-11C]arachidonic acid in 23 % decay corrected radiochemical yield within 52 min. The radiochemical purity of the final product was 98 %. In a typical run starting with 20 GBq [11C]O2, 760 MBq of [19-11C]arachidonic acid was obtained, with a specific activity of 1.6 GBq/μmol.

Methods have been developed for the alkylation of 5-oxazolinone derivatives in DMF in the presence of K2CO3, KOH, or diisopropylethylamine and a phase transfer catalyst as well as for the preparation ofα-methyl-phenylalanine,α-methylalanine,α-methylalanine, and the methyl ester of N-benzoyl-α-methylalanine. Increasing the initial concentration of the starting 5-oxazolinone in the reaction mixture leads to a sharp drop in the yield of reaction products due to side condensation reactions. The reaction of 2-phenyl-4-benzyl-5- oxazolinone with ethyl iodide gave a dimer namely, 3-(benzoylamino)-3,5-dibenzylpyrrolidine-2,4-dione.

1. To evaluate the sulfation pattern of anticoagulant active curdlan sulfates, a methylation method, based on the synthesis of alkylated alditol acetates, followed by GLC-MS examination, was developed. 2. By the specific cleavage of the sulfate esters, using solvolysis and the substitution of these liberated OH groups with ethyl iodide, a third kind of substitution was introduced in the alkylated alditol acetates, specifically replacing the former sulfate esters. 3. The primary OH group in position 6 had more than the 10-fold accessibility to sulfation, in comparison to the secondary OH groups in positions 2 and 4. 4. Products with a low DS were fairly homogenously substituted, having unsubstituted or selectively C6-sulfated glucose units. Increasing DS was associated with a loss of homogeneity as well as selectivity of the C6 sulfation. 5. Sulfation of C6-protected curdlan resulted in products with a higher content of sulfate groups in positions 2 and 4, and consequently a uniform charge distribution around the glucose monomer. 6. Besides the dependence on the DS and the MW, also the sulfation pattern influenced the anticoagulant activity. The higher the portion of the secondary linked sulfate esters, the higher the anticoagulant activity. The C6-protected curdlan sulfates had activities normally corresponding to higher DS and MW.

Single-ion enthalpies of transfer for transition-state anions of imidide ion plus ethyl iodide reactions have been determined in acetonitrile–methanol mixtures and have been partitioned into component enthalpies, ΔtHPHYSAN→MeOH and ΔtHSIAN→MeOH. Statistical analysis led to the empirical correlation incorporating nucleophiles and transition-state anions between specific interaction enthalpies, ΔtHSIAN→MeOH and the number of methanol molecules participating in the specific interaction with the anion. The molecular mechanistic origin of the specific interaction has been rationalized by introducing the concept of ‘effective atomic charge on the oxygen atom’ which has been derived through semi-emipirical MNDO/PM3 molecular orbital calculations.

To study its mechanism of antimalarial action, a tritium labelled analogue of (+/−)-chloroquine was required at high specific activity. Two synthetic methods were successfully employed. [3 - 3 H ] (+/−) -Chloroquine 2 was prepared by the catalytic tritium dehalogenation of an iodo precursor and [ N-ethyl- 3 H ] (+/−) -chloroquine 4 was synthesized by the alkylation of (+/−)-desethylchloroquine with [ 3 H ] ethyl iodide.

Phosphorescence spectra of nonphosphorescent or very weakly phosphorescent new UV absorbers, 2-methylphenyl cinnamate (MePC), 2-methylphenyl 4-methoxycinnamate (MePMC) and 2-methylphenyl 4-ethoxycinnamate (MePEC) have been observed by using external heavy atom effects of ethyl iodide in ethanol at 77 K. The lowest excited triplet (T(1)) energies of these new UV absorbers are lower than those of a widely used UV-A absorber, 4-tert-butyl-4'-methoxydibenzoylmethane (BM-DBM), in both keto and enol forms. The intermolecular triplet-triplet energy transfer from photolabile BM-DBM to MePMC was observed by measuring the time-resolved phosphorescence spectra. Electron paramagnetic resonance spectra have been observed for the T(1) states of these new UV absorbers in ethanol at 77 K by using benzophenone as a triplet sensitizer. The observed T(1) lifetimes, zero-field splitting (ZFS) parameters and molecular orbital calculations of the ZFS parameters suggest that T(1) states of these new UV absorbers posses mainly (3)ππ* character. The deactivation processes of the lowest excited singlet (S(1)) states are predominantly fluorescence and internal conversion to the ground (G) states in MePMC and MePEC, while the main deactivation process of the S(1) state of MePC is internal conversion to the G state. The molar absorption coefficients of MePMC and MePEC in the UV-A and UV-B regions are larger than that of most widely used UV-B absorber, octyl methoxycinnamate.

Tripyrrane analogues were prepared by reacting resorcinol or 2-methylresorcinol with 2 equiv of an acetoxymethylpyrrole in the presence of p-toluenesulfonic acid and calcium chloride. Following removal of the benzyl ester protective groups, the resorcinol-derived benzitripyrrane was reacted with a pyrrole dialdehyde to give an aromatic hydroxyoxybenziporphyrin. However, furan and thiophene dialdehydes gave highly insoluble products that could not be fully characterized. The methylresorcinol-derived tripyrrane analogue reacted with pyrrole, furan, thiophene, and selenophene dialdehydes to give unstable porphyrinoids that were further oxidized with [bis(trifluoroacetoxy)iodo]benzene to give stable benziporphyrin derivatives. These oxidized benziporphyrins showed strongly diatropic properties by proton NMR spectroscopy where the differences in chemical shifts (Δδ) were >18 ppm in some cases. The selenophene-derived system was further characterized by X-ray crystallography, and these results showed that one of the pyrrole subunits in this crowded structure was tilted by 21° relative to the mean macrocyclic plane. The tripyrrolic system reacted with silver(I) acetate to give the corresponding silver(III) organometallic complex. Regioselective alkylation with methyl or ethyl iodide and potassium carbonate gave diastereomeric mixtures of N-alkyl derivatives, and the N-ethyl substitution products showed highly diastereotopic characteristics.

Iodine is used in a wide variety of fields, among which are included industrial, pharmaceutical, nutritional, agricultural, electrical, and metallurgical. Iodine is produced as a nitrate ore by-product or from brines or seaweed. As found in nature it has only one stable isotope. Several radioactive isotopes have been prepared and have found use as radiopharmaceuticals or radioactive tracers for medical imaging. Iodine is the only halogen that is solid at ambient temperatures and pressures. Having the highest atomic weight of the common halogens, iodine begins to exhibit metallic properties. Besides exhibiting properties of luster and opacity, it is classed as a semiconductor of electricity. It is an essential human nutrient. Commercially available inorganic and organic compounds are described. Keywords: Occurrence; Properties; Manufacture; Economics; Analytical methods; Health and safety; Uses; Environmental concerns; Iodine; Solubility; Brines; catalysts; Stabilizers; Phtography; Animal feeds; Dyes; Inks; Colorants; Sanitary uses; Radioactive iodine; Pharmaceuticals; Water purification; Potassium iodide; Sodium iodide; Hydrogen iodide; Iodates; Methyl iodide; Methyline iodide; Thymol iodide; Ethyl iodide

This chapter is concerned with the reactions of metal salts (enolates) of active methylene compounds with alkylating agents such as alkyl halides to produce allyl derivatives. The first example of this reaction is found in the literature when Geuther prepared ethyl alpha-ethyl acetoacetate by the reaction of the sodium enolate of ethyl acetoacetate with ethyl iodide. The active methylene compounds considered in the chapter include malonic esters, cyanoacetic esters, malonitriles, monocarboxylic esters and mononitriles. These classes of compounds are characterized by the presence of one or more acidic hydrogen atoms attached to carbon. Only C-alkylation has been observed with active methylene compounds and are discussed here. Several alternative methods for the preparation of alkyl and aryl derivatives of carboxylic esters and nitriles have been included. Keywords: Alkylation; Esters; Nitriles; Malonic esters; Cyanoacetic esters; Active methylene compound; Alkylating agents; Side reactions; Substituted esters; Mononitriles; Monocarboxylic acids

The surface chemistry of ethyl iodide over a Pd(100) surface has been studied at 90-450 K with the aim of generating C 2 H 5 species. The methods used included Auger electron spectroscopy (AES), photoelectron spectroscopy (XPS and UPS), temperature-programmed desorption (TPD), and work function measurements. Ethyl iodide adsorbs molecularly on a Pd(100) surface at 90 K, and this adsorption is followed by a multilayer formation at high exposures. Adsorption of C 2 H 5 I is characterized by a work function decrease (2.00 eV at monolayer), indicating that adsorbed C 2 H 5 I has a large, positive outward dipole moment. The thermal dissociation

The Gibbs energies of activation of the Menschutkin reactions of trethylamine with ethyl iodide in 10 monoalcohols and nine dialcohols, were dissected into contributions from the initial state and transition state. To perform this study, the infinite dilution activity coefficient values of the solutes in the solvents, γ∞, were determined by the UNIFAC group-contribution method, using the modified Flory–Huggins equation in the combinatorial term. For triethylamine, the γ∞ values were calculated using group-interaction parameters from the VLE Parameter Table, due to the nonavailability of specific γ∞ UNIFAC interaction parameters for the relevant groups. For ethyl iodide, the γ∞ values were calculated using the group-interaction parameters from the specific γ∞ UNIFAC Parameter Table, except for the solvents diethylene glycol and triethlene glycol, where VLE parameters were used for the same reasons as explained above for the triethylamine. The results were compared with those obtained for the unimolecular decomposition of tert-butyl halides. For the Menschutkin reaction, we conclude that solvent disruption and reorganization to a state appropriate to solvating the molecular species is a dominant interaction mechanisim.

The bimetallic μ-malonyl complexes: {(η 5 -C 5 Me 5 (NO)(PPh 3 )Re[μ-(COCH 2 CO)-C 1 : C 3 ] Re(CO) 4 (Br)} − Li + ( 1 ), {(η 5 -C 5 Me 5 (NO)(PPh 3 )Re[μ-(COCH 2 CO)-C 1 : C 3 ]Re(CO) 4 (PMe 3 )} · Li + OSO 2 CF 3 − ( 2 ), and (η 5 -C 5 Me 5 )(NO)(PPh 3 ) Re[μ-COCH 2 CO)-C 1 ,O 3 :C 3 ]Re(CO) 4 ( 3 ) undergo carbon-carbon bond cleavage reactions of the malonyl ligand upon exposure to HCl. Deprotonation of (η 5 -C 5 Me 5 )Re(NO)PPh 3 (μ-η 1 ,η 2 -COCH 2 CO)Re(CO) 4 , ( 3 ), in THF solution and addition of CH 3 I leads to the C-alkylation product, (η 5 -C 5 Me 5 )Re(NO) PPh 3 )[μ-(COCH(CH 3 )CO)-C 1 ,O 3 :C 3 ]Re(CO) 4 ( 11 ), isolated as a single diastereomer (85% yield). Deprotonation of 11 and alkylation with CD 3 I leads to (η 5 -C 5 Me 5 )Re(NO)(PPh 3 )[μ-(COC(CH 3 )(CD 3 )CO)-C 1 ,O 3 :C 3 ]Re(CO) 4 ( 12 - d 3) with > 97% diastereoselectivity. Alkylation of the enolate anion derived from deprotonation of 11 with ethyl iodide led to isolation of (η 5 -C 5 Me 5 )(NO)(PPh 3 )Re{μ-[COCCH 3 =1cr,C(OCH 2 CH 3 )]- C 1 , O 3 : C 3 Re(CO) 4 ( 21 ) in 84% yield. Quenching of the enolate anion of 3 with excess ethyl iodide led to formation of an 11:89 mixture of (η 5 -C 5 Me 5 (NO)(PPh 3 )Re[μ-(COCHCH 2 CH 3 CO)- C 1 :C 3 , O 3 ]Re(CO) 4 ( 15 ) and(η 5 -C 5 Me 5 )(NO)(PPh 3 )Re[μ-(COCH=1cr; COCH 2 CH 3 )- C 1 , O 3 : C 3 ]Re(CO) 4 ( 16 ) in 87% combined yield. When the enolate anion of 3 was treated with allyl bromide, both C and O alkylation products (η 5 C 5 Me 5 )(NO)(PPh 3 )Re{μ-[COCH(CH 2 CH=1cr; CH2)CO]- C 1 : C 3 , O 1 Re(CO) 4 ( 17 ) and (η 5 -C 5 Me 5 )(NO)(PPh 3 )Re{μ-[COCH=1cr; C(OCH 2 CH=1cr; CH 2 )]- C 1 , O 3 : C 3 Re(CO) 4 ( 18 )were formed in a 32:68 ratio (84% combined yield). Alkylation with benzyl bromide gave (μ 5 C 5 Me 5 )(NO)(PPh 3 )Re[μ-(COCH=1cr; COCH 2 C 6 H 5 )- C 1 , O 3 : C 3 ]Re(CO) 4 ( 19 ) in 76% yield.

The interaction of ethyl iodide with Ni(100) surfaces has been examined by using thermal programmed desorption (TPD), X-ray photoelectron (XPS), and static secondary ion mass (SSIMS) spectroscopies. Ethyl iodide adsorbs molecularly on that surface below 100 K, and dissociates between 100 and 160 K to form ethyl species and iodine atoms. At low coverages the ethyl moieties decompose completely to form surface carbon and hydrogen atoms (which recombine and desorb at slightly above 300 K), but desorption of both ethylene and ethane is also observed at higher coverages. Ethylene forms via the elimination of a hydrogen atom from the beta position, and desorbs between 160 and 210 K depending on the initial coverage of ethyl iodide; ethane, on the other hand, is generated mostly by a direct recombination of ethyl species with hydrogen originating either from adsorption of background gases or from the β-hydride elimination reaction.

Cellulose derivatives specifically substituted at the primary hydroxyl groups, 6-O-alkylcelluloses, were prepared from 6-O-tritylcellulose (trityl = triphenylmethyl). In the preferred procedure, the 6-O-tritylcellulose was first completely allylated in dimethyl sulfoxide (Me2SO), and subsequently detritylated with hydrogen chloride to yield 2,3-di-O-allylcellulose. This product was isomerized into 2,3-di-O-(1-propenyl)cellulose with potassium tert-butoxide in Me2SO. The polymer thus prepared was then alkylated completely with methyl or ethyl iodide in Me2SO containing a trace of water. The alkylated polymer was finally treated with 0.1 M HCl in aqueous 90% methanol at room temperature to remove the 1-propenyl groups. The products were shown by Fourier-transform infrared spectroscopy, 13C nuclear magnetic resonance spectroscopy, and gas-liquid chromatographic analysis to be uniformly substituted at the 6 position.

Nucleophilic reactivity and solvation patterns for succinimidide and phthalimidide ions have been characterized through three procedures, kinetic and enthalpy of solution measurements in aceto-nitrile-methanol mixtures, and enthalpy of reaction measurements in acetonitrile. Quantitative analysis indicates that activation enthalpy vs. activation entropy correlation is more sensitive and versatile than activation enthalpy vs. reaction ethalpy correlation as the method for detecting the effects of various molecular interactions on rates of reaction. Any essential difference in nucleophilic reactivities and in solvation patterns was not observed between imidide and carboxylate ions, but a significant difference is found on the pKa values in the aqueous phase and on the enthalpy of reaction with ethyl iodide in acetonitrile.

The cycloadduct 1a of anthracene and the labile thioaldehyde, ethyl thioxoacetate 2a, has been converted into the α-lithio derivative 1b with lithium diisopropylamide (LDA). Subsequent treatment with, separately, methyl iodide, ethyl iodide, allyl bromide and benzyl bromide gave the corresponding 12-‘alkyl’ derivatives 1c–f. Each derivative, when heated in toluene at 111 °C, dissociates to liberate anthracene and a thioketone 2, which can be trapped in situ with 2,3-dimethylbuta-1,3-diene 3 to afford the corresponding 2-substituted dihydrothiine 4 in good yield. The same set of products 4 was obtained directly by α-alkylation of the parent dihydrothiine 4a. Similarly, the 12-methyl anthracene adduct 1c gives, with cyclopentadiene and cyclohexadiene, the stereoisomeric cycloadducts 5 and 6, and 7 and 8 of the cyclic dienes and ethyl 2-thioxopropionate 2c. When treated with LDA and methyl iodide, the thioaldehyde adducts 9a and 13a of cyclopentadiene and cyclohexadiene undergo rearrangement and S-methylation, rather than C-methylation, and afford the cyclopropanecarboxylates 10a and 14a. The methyl and ethyl sulphonium salts 17a–b of the parent dihydrothiine 4a rearrange similarly to give the cyclopropanecarboxylates 19a–b. Methylation of the dilithio derivatives of the cycloadducts of thioxoacetic acid has also been investigated. The cyclopropanecarboxylic acid 14b was found to rearrange slowly in the crystalline state to give the epimeric γ-lactones 15 and 16.

The ylidene derivatives of cyanothioacetamide 1a–d reacted with ethyl acetoacetate to give the pyridinethiol derivatives 2a–d. Compounds 2a–d were used as starting material for the synthesis of several heterocyclic compounds. Reactions with hydrazine hydrate, ethyl iodide, methyl chloroacetate and α-chloro ethyl acetoacetate gave the pyridine and annelated pyridine derivatives 5a–d, 6a–d, 7a, 8b–d, and 12a–d, respectively. Compounds 7a, 8b–d and 12a–d reacted with hydrazine hydrate to yield the annelated pyridines 10a–d and 15a–d, respectively.

Reaction of 3-cyano-quinolin-2(1 H )-thione ( II ) with ω-bromoacetophenones gave 3-amino-2-aroyl-thieno[2,3- b ]quinolines ( IVa - IVd ). Whereas, interaction of II with chloroacetanilides yielded the corresponding thioesters Va - Vc which cyclized into 3-amino-2-arylcarbamoylthiene[2,3- b ]quinolines ( VIa - VIc ) on treatment with ethoxide. Compounds VIa - VIc were reacted with nitrous acid, triethyl orthoformate and carbon disulfide to afford the fused polycyclic compounds VIIa - VIIc , VIIIa - VIIIc and IXa - IXc , respectively. Also treatment of IXa - IXc with ethyl iodide gave 3-ethylthio derivatives Xa - Xc . Moreover, refluxing of VIa - VIc with acetic anhydride resulted in the formation of oxazinone XI which recyclized into pyrimidinones XIIIa - XIIIc upon reaction with aromatic amines.

The energetics of the Menshutkin reaction between triethylamine and ethyl iodide have been computed using B3LYP and MP2 with the LANL2DZ, LANL2DZd, SVP, MIDI!, 6-311G(d,p), and aug-cc-PVTZ basis sets. Small- and large-core energy-consistent relativistic pseudopotentials were employed. Solvent effect corrections were computed from QM/MM Monte Carlo simulations utilizing free-energy perturbation theory, PDDG/PM3, and both a nonpolarizable OPLS and polarizable OPLS-AAP force field. The B3LYP/MIDI! theory level provided the best DeltaG(++) values with a mean absolute error (MAE) of 4.9 kcal/mol from experiment in cyclohexane, CCl(4), THF, DMSO, acetonitrile, water, and methanol. However, the relative rates in cyclohexane, and to a certain extent CCl(4), were determined to be greatly underestimated when using the nonpolarizable OPLS force field. An overall reduction in the MAE to 3.1 kcal/mol using B3LYP/MIDI!/OPLS-AAP demonstrated the need for a fully polarizable force field when computing solvent effects for highly dipolar transition structures in low-dielectric media. The MAEs obtained with PDDG/PM3/OPLS and OPLS-AAP of 5.3 and 3.8 kcal/mol, respectively, provided comparable results to B3LYP at a fraction of the computational resources. The large rate accelerations observed in the reaction were correlated to an increased stabilization of the emerging charge separation at the transition state via favorable solute-solvent interactions.

This review considers the role of closed-ring intermediates in chemistry, in general, and focuses on recent experimental and theoretical works that provide compelling evidence for a fivemembered ring intermediate in the gas phase. The reactions of oxygen atoms with ethyl iodide and larger alkyl iodides produce HOI and a corresponding ethylenic compound via attack of the oxygen atom at the iodine and closure of the five-membered ring between the oxygen and a hydrogen on the beta-carbon. Detailed results are gathered from infrared chemiluminescence and molecular beam scattering, as well as new kinetics and product yield experiments. The theoretical calculations fully support and characterize the novel reaction mechanism.

The electrogenerated base of 2-pyrrolidone reacts with amines and anilines yielding the corresponding alkyl and aryl carbamates, after addition of carbon dioxide and ethyl iodide. Arylcarbamic esters are obtained in very good yields under mild reaction conditions with respect to the methods so far reported.

2-Amino-6-(3-methyl-5-oxo-1-phenyl-2-pyrazolin-4-yl)-4-phenylpyridine-3-carbonitrile (1) obtained by the reaction of 4-(1-iminoethyl)-3-methyl-1-phenyl-2-pyrazolin-5-one with benzylidenemalononitrile, was reacted with triethyl orthoformate followed by hydrazine hydrate, acetic anhydride, acetyl chloride, alkyl halides, benzoyl chloride, sulphuric acid followed by formamide, phenyl isothiocyanate, carbon disulphide followed by ethyl iodide, formamide, trichloroacetonitrile, nitrous acid, giving new oxopyrazolinylpyridines (2,3,5,6,8,9,10) and related pyridopyrimidines (11-17) and pyridotriazine (18).

The dissociative photoionization onsets of Br and I loss reactions were measured for C(2)H(5)Br and C(2)H(5)I, respectively, by threshold photoelectron photoion coincidence (TPEPICO) spectroscopy to establish the heats of formation of these two basic ethyl halides. The appearance energy of ethyl cation from ethyl bromide was found to be 1074.2 +/- 0.8 kJ mol(-1), and that from ethyl iodide was found to be 1016.4 +/- 0.8 kJ mol(-1). The heats of formation of ethyl bromide and ethyl iodide are interconnected through the ethyl cation. In establishing the thermochemistry of the ethyl halides, the ethyl cation heat of formation was concluded to be 915.5 +/- 1.3 kJ mol(-1) on the basis of a recent value for ethyl radical heat of formation and the well-established ionization energy and on the basis of ab initio isodesmic calculations using recent PEPICO data. Using this anchor, we obtained the following heats of formation: Delta(f)H(0K) degrees[EtBr] = -40.8 +/- 1.5 kJ mol(-1) and Delta(f)H(0K) degrees[EtI] = 6.3 +/- 1.5 kJ mol(-1). These results are more consistent with the higher EtBr heats of formation values in the literature, contrary to recent findings. For ethyl iodide, the latest calorimetric value does not agree within the claimed accuracy.

The ylidene derivatives of cyanothioacetamide 1a–d reacted with ethyl acetoacetate to give the pyridinethiol derivatives 2a–d. Compounds 2a–d were used as starting material for the synthesis of several heterocyclic compounds. Reactions with hydrazine hydrate, ethyl iodide, methyl chloroacetate and α-chloro ethyl acetoacetate gave the pyridine and annelated pyridine derivatives 5a–d, 6a–d, 7a, 8b–d, and 12a–d, respectively. Compounds 7a, 8b–d and 12a–d reacted with hydrazine hydrate to yield the annelated pyridines 10a–d and 15a–d, respectively.

The effect of solvent polarity and external heavy atom (ethyl iodide) on the fluorescence properties of 2-tolouidino-6-naphthalene-sulphonate (TNS) and 1-anilino-8-naphthalene-sulphonate (ANS) have been studied. For ANS with rise in polarity, a monotonic decrease of fluorescence yield (α f ) and lifetime (τ f ) is observed while ethyl iodide was found to have negligible effect. For TNS at low polarity α f and τ f are found to increase with rise in polarity, while ethyl iodide causes a decrease in τ f . At high polarity [ E T (30) > 51] behaviour of TNS is more or less similar to that of ANS. It is proposed that polarity-dependent, twisted intramolecular charge transfer is the main non-radiative process for ANS at all polarities [ E T (30) = 36–63] and for TNS only at high polarity. At low polarity intersystem crossing is the main non-radiative pathway for TNS.

CsSO4F reacted at room temperature, or at 35°C in acetonitrile with various heteroatom-containing organic molecules, and three types of transformations have been observed. Fluoro substitution process took place with triphenylmethane, triphenylsilane, triphenylchlorosilane, 4-tert-butylphenol, benzaldehyde, and octanal, thus forming fluorotriphenylmethane, fluorotriphenylsilane, 2-fluoro-4-tert-butylphenol, benzoyl fluoride, or octanoyl fluoride in high yields. Substitution reaction was accompanied by fluoroaddition process in the case of 2-fluoro-4-tert-butylphenol, where 2,2-difluoro-4-tert-butylcyclohexadienon-4,6 was isolated. CsSO4F easily oxidised secondary alcohols to ketones, and 1,2-dihydroxy-4-tert-butylbenzene to quinone derivate. Oxygenation process was observed in the case of triphenylphosphine, and dibenzotiophene, while ethyl iodide was transformed to ethyliodo(III) difluoride. Solvent plays an important role in these reactions, being successfully performed in CH3CN, and completely inhibited in CH2Cl2, while different shapes of the effect on fluorination of various organic molecules were observed by altering solvent nature by successive mixing of CH3CN with CH2Cl2.

The enolate of 3 beta-hydroxy-5 alpha-cholest-8(14)-en-15-one (II), formed upon treatment of II with potassium tert-butoxide in tert-butanol, was alkylated with ethyl iodide. In addition to the major products, 3 beta-hydroxy-14 alpha-ethyl-5 alpha-cholest-7-en-15-one and its 3 beta-ethyl ether, small amounts of 3 beta-hydroxy-7 alpha-ethyl-5 alpha-cholest-8(14)-en-15-one (V), 3 beta-hydroxy-16 alpha-ethyl-5 alpha-cholest-8(14)-en-15-one (VI) and the 3 beta-ethyl ether of VI were isolated. When the enolate of II was formed by treatment with lithium diisopropylamide in tetrahydrofuran, the same alkylation furnished VI as the major product. Reduction of VI with lithium aluminum hydride gave 16 alpha-ethyl-5 alpha-cholest-8(14)-ene-3 beta, 15 alpha-diol (IX) and its 15 beta epimer X, which were separated by column chromatography. Full 1H and 13C nuclear magnetic resonance (NMR) assignments, augmented by nuclear Overhauser effect difference spectra for VI, established the stereochemistry of these diols at C-15 and C-16. The NMR results indicate that the 16 alpha-ethyl group affects the side-chain conformation. The effects of II, V, VI, IX and X on the levels of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity were studied in CHO-K1 cells. With the exception of IX, each of the compounds reduced the levels of HMG-CoA reductase activity. The order of potency with respect to suppression of the elevated levels of HMG-CoA reductase activity induced by transfer of the cells to lipid-deficient medium, was II greater than V greater than VI greater than X.

The chemistry and kinetics of singlet (pentafluorophenyl)nitrene were studied by chemical trapping and laser flash photolysis techniques. Photolysis of pentafluorophenyl azide in cyclohexane, benzene, diethylamine, pyridine, tetramethylethylene, tetrahydrofuran, dimethyl sulfoxide, and dimethyl sulfide forms adducts in fair to good yeilds. At ambient temperature singlet (pentafluorophenyl) nitrene is intercepted, and intersystem crossing to the lower energy triplet state is unimportant. Triplet nitrene chemistry can be achieved by benzoylbiphenyl photosensitization, the presence of methanol or ethyl iodide, or by lowering the reaction temperature below O°C

Results of a series of experimental investigations with CH3OH, C2H5I and C6H5CH3 are reported. Vapor pressures of the pure substances and T, p, x, y data of two binary and one ternary system were determined in an ebulliometer; the enthalpy of mixing of equimolar mixtures for two binaries was measured in a simple calorimetric experiment, and the density of the two binary systems was measured as a function of composition at 293.15 K with a vibrating U-tube densimeter. The consistency of the binary vapor-liquid equilibrium (VLE) data was tested. Binary parameters in various gE models were fitted and new UNIFAC parameters were determined. Experimental hE were compared with hE values calculated from VLE data.

The reaction of4-acylamino-3-cyano-1,2-dihydrospiro(naphthalene-2,1-cyclohexanes) with hydrogen chloride yields 2-substituted 4-oxo-3,4,5,6-tetrahydrospiro(benzo[h]quinazoline-5,1-cyclohexanes). It was found that when the latter are condensed with methyl iodide, N-alkylation takes place exclusively. Alkylation with ethyl iodide in analogous conditions yields a mixture of O- and N-substituted products.

Iodine-doped cubic ZnCdS films have been grown on GaAs by low-pressure metalorganic vapor phase epitaxy using ethyl iodide as a donor dopant source. And the electrical and optical properties have been investigated. It has been found that the maximum electron density of the doped-ZnCdS films is about 10 19 cm -3 . In the photoluminescence properties, near-band-edge emissions and self-activated emissions relating to the iodine donors are observed. Furthermore, the electrical properties greatly depend on the solid composition. It has been found that the electron density changes abruptly at the solid composition of about 0.5. From the photoluminescence measurements and the secondary ion mass spectroscopy analysis, this has been attributed to the increase in the concentration of donor-compensation centers there.

The chemisorption and thermal decomposition of ethyl iodide on Pt(111) have been studied by reflection-absorption infrared spectroscopy (RAIRS). At 100 K the chemisorption is molecular, and a change in adsorption geometry occurs from a flat to an upright orientation as the surface coverage is increased. Ethyl, ethylene and ethylidyne were identified at higher temperatures by IR spectrometry as decomposition products. As a consequence of the coverage-dependent orientation of the ethyl iodide molecules on the surface, different reaction mechanisms are operative at low and high coverages. At low coverages, ethyl iodide decomposes quantitatively between 150 and 200 K through a C-I bond breaking step followed by immediate dehydrogenation to ethylene. At saturation coverages, some ethylene formation competes with molecular desorption around 200 K (analogous to the low coverage decomposition), but additional ethylene is produced between 200 and 240 K in a slower, reversible reaction which involves the formation of ethyl species as stable intermediates. Ethylene further decomposes around 300 K to form ethylidyne.

Reaction of 3-cyano-quinolin-2(1H)-thione (II) with ω-bromoacetophenones gave 3-amino-2-aroyl-thieno[2,3-b]quinolines (IVa-IVd). Whereas, interaction of II with chloroacetanilides yielded the corresponding thioesters Va-Vc which cyclized into 3-amino-2-arylcarbamoylthiene[2,3-b]quinolines (VIa-VIc) on treatment with ethoxide. Compounds VIa-VIc were reacted with nitrous acid, triethyl orthoformate and carbon disulfide to afford the fused polycyclic compounds VIIa-VIIc, VIIIa-VIIIc and IXa-IXc, respectively. Also treatment of IXa-IXc with ethyl iodide gave 3-ethylthio derivatives Xa-Xc. Moreover, refluxing of VIa-VIc with acetic anhydride resulted in the formation of oxazinone XI which recyclized into pyrimidinones XIIIa-XIIIc upon reaction with aromatic amines.

In this work zinc azaphthalocyanines (AzaPcs) from the group of tetrapyrazinoporphyrazines and zinc azanaphthalocyanines from the group of tetra[6,7]quinoxalinoporphyrazines (TQP) with eight diethylaminoethylsulfanyl substituents were synthesized. Tertiary amines were later quaternized with ethyl iodide to obtain water-soluble photosensitizers (PSs). Quaternized compounds showed high singlet oxygen quantum yields as determined in DMF by monitoring decomposition of 1,3-diphenylisobenzofuran. In water medium, quaternized AzaPc derivatives appeared in monomeric form in a wide range of concentrations while quaternized TQP derivatives showed aggregation at higher concentrations (over 1 microM). Photodynamic activity was tested on Hep2 cells using light of lambda > 640 nm. Both quaternized dyes showed high photodynamic activity (IC(50) = 104 and 220 nm for AzaPc and TQP, respectively). Dark toxicity was not detected even at the highest concentration used in in vitro tests (200 microM) which indicates a promising therapeutic index of these new substances. Tested compounds localized inside the cells mainly within the lysosomes thus suggesting an endocytic mechanism of cellular uptake. No localization within mitochondria was detected. A great advantage of TQP derivatives over other PSs is their very strong absorption at 747 nm that allows activation at wavelengths penetrating deeper into human tissues.

The reaction of chlorine atoms with alkyl iodides can play a role in the chemistry of the marine boundary layer. Previous studies have shown that at room temperature the reaction takes place via a complex mechanism including adduct formation. For the Cl + ethyl iodide reaction results on the thermodynamics of adduct formation and on the product yields are inconsistent. The kinetics of the reaction Cl + C(2)H(5)I have been studied by the direct observation of the HCl product in real time flash photolysis/IR absorption experiments as a function of temperature from 273 to 450 K. At temperatures above 375 K kinetic measurements confirm a direct process and the rate coefficient determined (4.85 +/- 0.55) x 10(-11) exp((-363 +/- 51)/T) cm(3) molecule(-1) s(-1) is in good agreement with previous direct determinations. Product yield studies have also been undertaken by comparing the HCl signal from Cl + C(2)H(5)I with that from a calibration reaction which shows that HCl is the sole product of the reaction at these temperatures. Yield studies with selectively deuterated ethyl iodide demonstrate that abstraction occurs predominantly from the alpha site, with the selectivity decreasing with temperature. Extrapolation of the yield data to 298 K predicts an alpha:beta ratio of 0.68:0.32. At temperatures between 273 and 325 K a biexponential growth was observed for the HCl signal consistent with adduct formation. Analysis of the HCl time profiles allowed the extractions of the forward and reverse rate coefficients for adduct formation and hence the calculations of the thermodynamic properties of adduct formation. A third law analysis yields a value of Delta(r)H = (-54 +/- 4) kJ mol(-1). The value of Delta(r)H is in good agreement with a previous third law determination (J. J. Orlando, C. A. Piety, J. M. Nicovich, M. L. McKee, P. H. Wine, J. Phys. Chem. A, 2005, 109, 6659).

Ultraviolet irradiation of aqueous solutions of iodide/iodate ion containing low molecular weight organic acids generates volatile iodine species that are amenable to detection by atomic spectrometry. In the presence of formic, acetic or propionic acids, photo-chemical generation results in the formation of HI, methyl- and ethyl-iodide respectively, the latter two products being directly identified by gas chromatography–mass spectrometry. Deuterium and 13C-labeled reagents were employed to elucidate the provenance of the alkyl group. Use of 13CH3–COOH produced 13CH3–I; deuterated acetic acid (D3C-COOD) resulted in the formation of CD3–I. These observations indicate direct transfer of the alkyl group from the carboxylic acid to iodide, consistent with the suggestion that the mechanism of synthesis involves radical induced reactions.

Series of compounds 1,4-bis-(2-aryl/alkyl-amino-[1,3,4]-oxadiazol-5-vl)-benzenes, 1,4-bis-(2-aryl/alkyl-amino-[1,3,4]-thiadiazol-5-yl)-benzenes and 1,4-bis-(3-mercapto-4-aryl/alkyl-[1,2,4]-triazol-5-yl)-benzenes have been synthesized by the oxidative cyclization of di-(N-aryl/alkyl thiocarbamido) terephthalamides using alkaline ethanolic solution of iodine containing potassium iodide, ortho-phosphoric acid and aqueous potassium hydroxide solution respectively. These compounds on acetylation afforded bis-acetyl derivatives, on benzoylation afforded bis-benzoyl derivatives and on reaction with ethyl iodide afforded bis-ethylmercapto derivatives respectively. These compounds have been assayed for their antimicrobial activity against gram-positive as well as gram-negative microorganisms.

Condensation of sebacic acid dihydrazide (1) with aryllalkyl isothiocyanates (2a-g) gives bis-(N-aryl/alkyl-thiocarbamido)-scbacic acid diamides (3a-g), which on reaction with o-phosphoric acid yields 1,8-bis-(2-aryl/alkylamino-l,3,4-thiadiazol-5-yl)-octanes (4a-g). 1,8-Bis-(3-mercapto-4-aryl/alkyl-1,2,4-triazol-5-yl)-octanes (5a-g) were obtained by a similar condensation of compounds (3a-g) with aqueous KOH, which on reaction with ethyl iodide in the form of dihydroiodides have been isolated (6a-g). These on basification with aq. ammonia solution afforded free bases (7a-g). Compounds (4a-g) on benzoylation with benzoyl chloride and NaOH affords benzoyl derivatives (8a-g). The structures of all these compounds were confirmed on the basis of elemental analysis and spectral data and evaluated for their antimicrobial activity against gram positive and gram negative bacteria.

International audience; Carbon dioxide sequestration was studied by synthesizing diethyl carbonate (DEC) from ethanol and CO2 under supercritical conditions in the presence of potassium carbonate as a base. The co-reagent was ethyl iodide or a concentrated strong acid. This sequestration reaction occurs in two steps which were studied, separately and in a one-pot reaction. An organic-inorganic carbonate hybrid, potassium ethyl carbonate (PEC) is generated at the end of the first step. This intermediate was characterized and was found to be a target molecule for CO2 capture. Different co-reactants, such as ethyl iodide and concentrated strong Bronsted acid, were compared in the second step and used to investigate the reactivity of the hybrid. With ethyl iodide as the co-reactant, one-pot DEC synthesis gave higher yields (46%) than two-step production. The supercritical CO2 acts as a swelling solvent and compatibilizing agent in the reaction medium, favoring interactions between ethanol and CO2 and between PEC and ethyl iodide. The use of a phase transfer catalyst (PTC) increased DEC production (yield 51%) without increasing the amount of diethyl ether (DEE) produced as a by-product (yield 2%).

2-Phenyl-3,1-benzoxazin-4-one (1) reacted with a mixture of hydrazine hydrate and carbon disulphide in the presence of potassium hydroxide to give 2-(o-benzoylaminophenyl)-1,3,4-oxadiazolin-5-thione (2) which was also formed in better yield by the reaction of o-benzoylaminobenzhydrazide (5) with carbon disulphide and potassium hydroxide. The reaction of (2) with ethyl iodide, formaldehyde in the presence of morpholine, and with amines was also investigated.

Excess molar Gibbs free energies GEm for (ethyl iodide plus benzene, toluene, o-xylene, m-xylene or p-xyleae) over the whole range of composition have been measured experimentally at 308.15 K from the measured vapour pressures. The results for GmE values of these mixtures suggest the existence of weak specific interactions of electron donor-acceptor type in which aromatic hydrocarbons behave as electron donors. The values of GmE have also been computed from the statistical theory of Flory. The Flory theory gave poor agreement between experimental and calculated values.

The excess Gibb's free energy of mixing, GE, for ethyl iodide+toluene at 25°C have been obtained from the measured vapor pressuure data. The HE and GE values for ethyl iodide+toluene are positive throughout the ethyl iodide concentration range and GE>HE. The results have been analyzed in terms of Flory and ideal associated model theory of nonelectrolyte solutions. It has been observed that the ideal associated model approach which assumes the presence of AN and A2B molecular species describes well (within±10 J-mol−1 in the worst case) the general dependence of HE on XA (mole fraction of ethyl iodide) over the whole composition range for ethyl iodide+toluene mixtures. The equilibrium constants for A+A⇆ AB and 2A+B⇆A2B reactions along with the enthalpies of formation of AB and A2B molecular species have been calculated.

The synthesis of [11C]phenobarbital (3a), [11C]pentobarbital (3b) and [11C]amobarbital (3c) labelled in the 5-[1-11C]ethyl position is reported. The malonic esters if RCH(CO2Et)2 [R = phenyl- (1a, 1-methylbutyl-(1b and 3-methylbutyl- (1c)] were alkylated with [1-11C]ethyl iodide prepared from [11C]carbon dioxide. Ring closure of the 2-[1-11C]ethyl-labelled malonic esters (2a–c) with urea afforded 5-[1-11C]ethyl-3a–c in synthesis times of 42–47 min, counted from [11C]carbon dioxide. In typical syntheses starting with 3 GBq (81 mCi) [11C]carbon dioxide, 150–215 MBq (4–6 mCi 3a–c were produced in 25–30% decay corrected radiochemical yields with radiochemical purities greater than 98%.

The rate constants of the reaction of triethylamine with ethyl iodide have been measured in 15 solvents at the temperatures of 293, 313, 333 and 373 K. The solvent characteristics by Kamlet and Taft and those by Pytela have been found to be excellently applicable to evaluation of influence of medium on this reaction at all the temperature mentioned. However, these methods give different results with regard to the proton-donor effects of solvents on the reaction.

The cycloadduct 1a of anthracene and the labile thioaldehyde, ethyl thioxoacetate 2a, has been converted into the α-lithio derivative 1b with lithium diisopropylamide (LDA). Subsequent treatment with, separately, methyl iodide, ethyl iodide, allyl bromide and benzyl bromide gave the corresponding 12-‘alkyl’ derivatives 1c–f. Each derivative, when heated in toluene at 111 °C, dissociates to liberate anthracene and a thioketone 2, which can be trapped in situ with 2,3-dimethylbuta-1,3-diene 3 to afford the corresponding 2-substituted dihydrothiine 4 in good yield. The same set of products 4 was obtained directly by α-alkylation of the parent dihydrothiine 4a. Similarly, the 12-methyl anthracene adduct 1c gives, with cyclopentadiene and cyclohexadiene, the stereoisomeric cycloadducts 5 and 6, and 7 and 8 of the cyclic dienes and ethyl 2-thioxopropionate 2c. When treated with LDA and methyl iodide, the thioaldehyde adducts 9a and 13a of cyclopentadiene and cyclohexadiene undergo rearrangement and S-methylation, rather than C-methylation, and afford the cyclopropanecarboxylates 10a and 14a. The methyl and ethyl sulphonium salts 17a–b of the parent dihydrothiine 4a rearrange similarly to give the cyclopropanecarboxylates 19a–b. Methylation of the dilithio derivatives of the cycloadducts of thioxoacetic acid has also been investigated. The cyclopropanecarboxylic acid 14b was found to rearrange slowly in the crystalline state to give the epimeric γ-lactones 15 and 16.