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The catalytic system for ethanol carbonylation consists of rhodium with hydroiodic acid, ethyl iodide and lithium iodide as promoters exhibited an attractive catalytic activity at low water content (

We report the comparison of a series of 2D molecular crystals formed from the intermediates of the dehalogenation reaction of iodoethane versus various fluorinated iodoalkanes on Cu(111). High-resolution scanning tunneling microscopy enables us to distinguish the alkyl groups from the iodine atoms, and we find that the ethyl groups and iodine atoms formed from the dissociation of ethyl iodide are well mixed. However, fluorination of the alkyl tail changes this behavior and leads to local segregation of the two species on the surface. We postulate that the low-polarizability and relatively large dipole moment of the fluorinated species drive the ordered assemblies of the fluorinated alkyl species on the surface and discuss this in the context of how solvophobicity can drive the clustering of fluorinated groups and, hence, phase separation.

Carbonylation of ethanol is a potentially attractive route for propionic acid production, while its industrial practice is greatly hampered by the low space-time yield. To improve the reaction rate of ethanol carbonylation, a series of diphosphine ligands were investigated in the homogeneous rhodium complex catalyst system. The catalyst activity and stability were enhanced by using bis(diphenylphosphino)methane monosulfide (dppmS) as hemilabile diphosphine ligand and the space-time yield of propionic acid was increased significantly. In the presence of dppmS, not only the effect of ligand addition, the content of ethyl iodide, lithium iodide, and rhodium catalyst on catalytic performance were carried out, but also the reaction conditions were systematically investigated in a titanium alloy autoclave reactor. Consequently, the carbonyl space-time yield reached 6.21 mol·L−1·h−1 under the optimal reaction conditions. Additionally, the corresponding mechanism of ethanol carbonylation with addition of dppmS was proposed. A kinetic model of the reaction was established in the temperature range of 433–473 K. The reaction orders of catalyst, ethyl iodide, and iodide ion concentrations were determined to be 0.86, 0.36, and 0.20, respectively. The activation energy was found to be 25.23 kJ·mol−1. Residual error distribution n and a statistical test showed that the kinetic model is reasonable and acceptable.

1-Benzyl-3-ethylbenzimidazolium iodide (1) and 1-benzyl-3-(2′-nitrilebenzyl)benzimidazolium bromide (2) were prepared by the reaction of 1-benzylbenzimidazole with ethyl iodide or 2-bromomethylbenzonitrile to act as N-heterocyclic carbene (NHC) precursors. Bis-NHC silver(I) complexes having halide (3a and 4a) as well as hexafluorophosphate (3b and 4b) counterions were yielded by the reaction of NHC precursors with silver(I) oxide. Subsequent reactions of the silver(I) halide/hexafluorophosphate complexes with [PdCl2(CNCH3)2] in methanol afforded the NHC palladium(II) complexes (5 and 6) via carbene transfer method. All synthesized compounds were fully characterized by analytical and spectrometric methods. Preliminary catalytic studies evinced that the nitrile-functionalized palladium(II)-NHC complex 6 is highly active in the oxidation of 1-octene as well as styrene in the presence of aqueous hydrogen peroxide as an oxidizing agent. Both the olefins were oxidized to their corresponding oxidized products with 45-52% conversion with moderate selectivity in the presence of NHC palladium complexes, which acted as oxidation catalysts. In order to investigate the suggested structure of the title complexes, density functional theory was used to find the stable structures of the palladium complexes and their isomers. Geometry parameters, molecular orbital energies, electronic energy, band gap, and vibrational frequencies were calculated.

Ethanol carbonylation is a potential route to valuable C3 products. Here, Rh supported on porous, Cs-exchanged heteropolyacid Cs3PW12O40, is demonstrated as an effective catalyst for vapor-phase ethanol carbonylation, with higher selectivity and conversion to propionates than existing catalysts. Residual acidity or a Mo polyatom was strongly detrimental to yields. Propionate selectivity was maximized at 96% at 170 °C and with added H2O. The catalyst displayed stable selectivity over 30 h on stream and up to 77% conversion. Ethyl iodide is a required co-catalyst but at levels as low as 2% relative to ethanol. XPS and in situ XANES indicate partial Rh reduction, consistent with the formation of low-valent reactive intermediates and slow deactivation through formation of Rh nanoparticles. With further optimization and understanding, these Rh/heteropolyacid catalysts may lead to stable and selective catalysts for the production of propionates through ethanol carbonylation.

Nanochemistry is an emerging new field of chemistry, in particular of solid-state chemistry, which emphasizes the study and development of preparation methods of useful materials with nanometer-size dimensions (1–100 nm), as defined by Geoffry Ozin, a pioneer in the field. The direct synthesis of metal complexes and organometallic compounds from zerovalent metals is a known methodology that was well developed during the past 165 years, since the first preparation of Zn(CH 2 CH 3 ) 2 by Frankland from the direct reaction of metallic zinc powder and ethyl iodide. Although comparatively, the dimensions of the simplest and smaller nanoparticles are a thousand times larger than the most common coordination or organometallic compounds, there are several interesting characteristics that may serve as bridges to extrapolate several of the synthetic tools developed around the direct synthesis of metal complexes toward the preparation of inorganic nanomaterials. First of all, the surface of inorganic nanomaterials (metallic, metal oxides, or metal chalcogenides, among several others) is very reactive and unstable, unless a coordinating surfactant is used to coat the surface. It is relatively easy to understand that the surfactant behaves as a coordination ligand and that it may play an important role not only on stabilization, but also on the control of the structure and properties of the resulting nanomaterial. Here, we discuss several bridging concepts among coordination compounds and nanochemistry, and present direct synthesis as a novel and useful synthetic tool for the preparation of several useful and interesting inorganic nanomaterials.

The photoionization electron attachment ion mobility spectrometry (PI-EA-IMS), with photoelectrons formed by photoionization of organic compound like acetone, has been developed to study electron attachment reactions. With this apparatus, the rate constants for electron attachment to alkyl iodides including ethyl iodide (C 2 H 5 I), 1-propyl iodide (1-C 3 H 7 I), 1-butane iodide (1-C 4 H 9 I) and 2-propyl iodide (2-C 3 H 7 I) have been determined over the average electron energy from 0.29 to 0.96 eV. The rate constants are in the order of magnitude of ∼10 −9 cm 3 molecule −1 s −1 . The experimental measurements show that for straight-chain alkyl iodides, the values of the rate constants follow the order of: k (C 2 H 5 I) k (1-C 3 H 7 I) ≈ k (1-C 4 H 9 I) which can be explained by the energy threshold for the formation of iodine anion via dissociative electron attachment. For the isomers, 2-C 3 H 7 I has a lower rate constant than 1-C 3 H 7 I which may be caused by the effect of branched chain.

It has been demonstrated that alkylzinc halides efficiently destroy the passivating film on the zinc-copper pair in the course of its alkylation with ethyl bromide to give ethylzinc bromide. The alkylzinc halides efficiency is comparable to that of ethyl iodide and exceeds that of salts of transition or non-transition metals as well as of ultraviolet irradiation. Addition of alkylzinc halides or metal salts as well as ultraviolet irradiation have practically no effect on the developed reaction. The results have demonstrated that the organometallic component of the binary systems is polyfunctional; this permits a generalization of known features of a number of known methods promoting direct synthesis of organometallic compounds.

Summary Methods for the small scale synthesis of I-131 labelled iodine species relevant to severe nuclear accidents in light water reactors have been developed. The introduced methods allow the synthesis of impurity free, volatile, inorganic elemental iodine and volatile, organic iodides such as methyl- and ethyl iodide, as well as butyl iodide, chloroiodomethane, allyl iodide and benzyl iodide with ease. The radioactive iodine containing products are sufficiently stable to allow their storage for later use. Due to their volatility the liquid species can be easily converted into gaseous species and thus can be used in research in liquid and gaseous phase. The primary motivation for the development of these synthesis methods is to study the behaviour of volatile iodine species under the conditions of a severe nuclear accident in a light water reactor. Thus, the chemicals involved in the synthesis are chosen in a way to not generate impurities (chlorine and organic solvents) in the products which interfere with competing reactions relevant during a severe nuclear accident. Teknopox Aqua VA epoxy paint, which is used in Swedish light water reactor containments, and its reactions with the produced iodine species are described. The synthesised iodine species undergo chemisorption on paint films. Different to elemental iodine, the organic iodides are non-reactive with copper surfaces. The sorbed iodine species are partly re-released mainly in form of organic iodides and not as elemental iodine when the exposed paint films are heat treated. The partitioning and hydrolysis behaviour of gaseous methyl- and ethyl iodide between containment gas phase and water pools is found to be similar. The methods have been designed to minimise the use of harmful materials and the production of radioactive waste.

1-Trimethylsilyl, 1-R (R = Me, Et, i-Bu)-2,3,4,5-tetraphenyl-1-silacyclopentadiene [Ph4C4Si(SiMe3)R] are synthesized from the reaction of 1-trimethylsilyl,1-lithio-2,3,4,5-tetraphenyl-1-silacyclopentadienide anion [Ph4C4SiMe3]−•[Li]+ (3) with methyl iodide, ethyl iodide, and i-butyl bromide. The versatile intermediate 3 is prepared by hemisilylation of the silole dianion [Ph4C4Si]−2•2[Li]+ (2) with trimethylsilyl chloride and characterized by 1H-, 13C-, and 29Si-NMR spectroscopy. 1,1-bis(R)-2,3,4,5-tetraphenyl-1-silacyclopentadiene [Ph4C4SiR2] {R = n-Bu (7), t-Bu (8)} are synthesized from the reaction of 2 with n-butyl bromide and t-butyl bromide. Reduction of 7 and 8 with lithium under sonication gives the respective 3-silolenide 2,5-carbodianions {[Ph4C4Si(n-Bu)2]−2•2[Li]+ (10) and [Ph4C4Si(t-Bu)2]−2•2[Li]+ (11)}, which are characterized by 1H-, 13C-, and 29Si-NMR spectroscopy. Polarization of phenyl groups in 3 is compared with those of silole anion/dianion, germole anion/dianion, and 3-silolenide 2,5-carbodianions 10 and 11.

The surface reactions of ethyl iodide on GaAs(100) have been studied using Auger Electron Spectroscopy (AES), Low Energy Electron Diffraction (LEED) and Thermal Desorption Spectroscopy in conjunction with isotope scrambling experiments with deuterium. Ethyl iodide was found to adsorb dissociatively at room temperature, to form chemisorbed ethyl and iodine species. Recombinative desorption of molecular ethyl iodide competes with the further surface reactions of ethyl and iodine. The ethyl species undergoes β-hydride elimination reaction to form ethene, ethane and hydrogen, which all desorb into the gas phase. Iodine selectively etches surface gallium atoms as GaI, which subsequently desorbs at 520 K, and this species was the major halide etch product formed for all exposures of ethyl iodide. HI desorption forms a minor channel for the removal of surface iodine. As2 desorption occurs from arsenic-enriched surfaces for temperatures greater than 600 K, and it is postulated that at high surface concentrations of chemisorbed arsenic dimers, As4 desorption must also become feasible. LEED and AES studies show that repetitive exposure of the gallium-rich GaAs(100)-(4 × 1) surface with ethyl iodide followed by annealing to 700 K gives rise to the arsenicrich c(4 × 4) structure, and this observation is consistent with the thermal desorption data. A reaction scheme is proposed to account for the observed desorption products, and the etching behaviour of ethyl iodide is discussed in the light of the reaction mechanism elucidated. © 1998 Published by Elsevier Science B.V. All rights reserved.

Reaction of a benzocarbaporphyrin with methyl or ethyl iodide and potassium carbonate in refluxing acetone primarily afforded the 22-alkylation products. Subsequent metalation with palladium(II) acetate in refluxing acetonitrile gave the palladium(II) organometallic derivatives where the alkyl group had migrated to the 21-position.

A rapid and sensitive method for quantifying iodine in intact starch granules using gas chromatography is described with detection limits as low as 0.2% (w/w) iodine in starch. Sample preparation includes NaBH(4) reduction of the various iodine species associated with starch to the colorless soluble iodide ion, followed by its quantitative derivatization to EtI using Et(3)O(+)BF4- in CH(2)Cl(2). Identification and quantification of EtI is carried out by extraction and injection of the EtI so generated in CH(2)Cl(2) into a gas chromatography-mass spectrometer (GC-MS). Routine quantification of EtI was then performed using GC with a flame ionization detector (GC-FID). Results for different iodine:potassium iodide ratios of the initially bound iodine and for seven different starch matrices showed that in all cases regression coefficients for the standards were high (R(2)>0.96).

Acetyl iodide reacted with urea and its derivatives to give the corresponding N-substituted products. The reactions of acetyl iodide with thiourea, N,N′-dimethylthiourea, imidazolidine-2-thione, and hexahydropyrimidine-2-thione resulted in the formation of S- or N-acetyl derivatives, depending on the temperature and structure of the sulfur functionality (thione or thiol). By contrast, in the reaction of acetyl iodide with N,N′-bis(3-triethoxysilylpropyl)thiourea one ethoxy group on the silicon atom was replaced by iodine with formation of N-{3-[(diethoxy)iodosilyl]propyl}-N′-[3-(triethoxysilyl)propyl]thiourea. The latter decomposed on heating to give 3-triethoxysilylpropyl isothiocyanate and silicon-containing polymer with the composition C45H97IN6O14.5S3Si6.

The programmed temperature desorption method was used to study the interaction of oxygen with the surface of a polycrystalline silver catalyst promoted with iodine. Ethyl iodide almost did not interact with the unoxidized surface of silver. The adsorption of C2H5I on the oxidized catalyst surface resulted in the formation of two adsorbed iodine forms, silver iodide and iodine deeply dissolved in subsurface silver crystal lattice layers. The character of oxygen adsorption from the iodine-containing surface of the catalyst was determined by the amount and form of adsorbed iodine. In the presence of a iodine-containing promoter, the concentration of oxide-like oxygen sharply decreased, and the amount of strongly bound atomically adsorbed oxygen responsible for the selective transformation of ethylene glycol into glyoxal increased.

Activated carbon-supported Ni catalysts for vapor phase carbonylation of ethanol to propionic acid in the presence of ethyl iodide as promoter were investigated. Under optimum reaction conditions, the conversions of carbon monoxide and ethanol were measured to be 81.4% and 98.4%, respectively, while the selectivity for propionic acid was found to be 98.65%. The catalyst was stable within 48 h on stream. XRD and XPS methods were used to characterize the structures and surface properties of the fresh and tested catalysts. The characterization results indicated that aggregation of nickel particles and formation of nickel iodide on the catalyst surface should be responsible for the deactivation of the catalysts.

X-ray photoelectron spectroscopy (XPS) studies revealed that potassium on Mo 2 C/Mo(100) induced cleavage of the C-I bond in adsorbed CH 3 I even at ∼100 K. The temperature of complete C-I bond breaking occurred 60-80 K lower compared to the clean surface. Preadsorbed potassium also influenced the reaction pathway of adsorbed CH 3 formed. It decreased its self-hydrogenation into methane and facilitated the coupling reactions into ethane and ethylene below 200 K. High-resolution electron energy loss spectroscopy (HREELS) confirmed formation of adsorbed CH 3 species and revealed its thermal stability. Potassium exerted a similar influence on the chemistry of C 2 H 5 I on Mo 2 C/Mo(100) surface. Rupture of the C-I bond also occurred more easily on K-covered surface. Ethyl species, the primary product of the dissociation, dehydrogenated into ethylene on one hand and hydrogenated into ethane on the other. Rupture of the C-C bond was not observed even at high potassium coverage. Illumination of coadsorbed layers promoted further dissociation of the C-I bond in both compounds at ∼100 K.

The importance of the iodine chemistry in the atmosphere has been demonstrated by recent observations. The uptake of ethyl iodine on black carbon surface was investigated at 298 K for the first time. Degussa FW2 (an amorphous black carbon comprising medium oxides) was used as black carbon sample. Black carbon surface was found to be deactivated in reaction with C2H5I, and the uptake coefficient (γ) was dependent on the time of exposure. The value of (2.3±0.9)×10−2 was determined for the initial uptake coefficient (γ 0). The result suggests that the heterogeneous loss of C2H5I on carbonaceous aerosols may be important under the atmospheric conditions.

Compounds labelled with 11C (β+, t1/2 = 20.4 min) are used in positron emission tomography (PET), which is a quantitative non-invasive molecular imaging technique. It utilizes computerized reconstruction methods to produce time-resolved images of the radioactivity distribution in living subjects.The feasibility of preparing [11C]methyl iodide from [11C]methane and iodine via a single pass through a non-thermal plasma reactor was explored. [11C]Methyl iodide with a specific radioactivity of 412 ± 32 GBq/µmol was obtained in 13 ± 3% decay-corrected radiochemical yield within 6 min via catalytic hydrogenation of [11C]carbon dioxide (24 GBq) and subsequent iodination, induced by electron impact.Labelled ethyl-, propyl- and butyl iodide was synthesized, within 15 min, via palladium-mediated carbonylation using [11C]carbon monoxide. The carbonylation products, labelled carboxylic acids, esters and aldehydes, were reduced to their corresponding alcohols and converted to alkyl iodides. [1-11C]Ethyl iodide was obtained via palladium-mediated carbonylation of methyl iodide with a decay-corrected radiochemical yield of 55 ± 5%. [1-11C]Propyl iodide and [1-11C]butyl iodide were synthesized via the hydroformylation of ethene and propene with decay-corrected radiochemical yields of 58 ± 4% and 34 ± 2%, respectively. [1-11C]Ethyl iodide was obtained with a specific radioactivity of 84 GBq/mmol from 10 GBq of [11C]carbon monoxide. [1-11C]Propyl iodide was synthesized with a specific radioactivity of 270 GBq/mmol from 12 GBq and [1-11C]butyl iodide with 146 GBq/mmol from 8 GBq.Palladium-mediated hydroxycarbonylation of acetylene was used in the synthesis of [1-11C]acrylic acid. The labelled carboxylic acid was converted to its acid chloride and subsequently treated with amine to yield N-[carbonyl-11C]benzylacrylamide. In an alternative method, [carbonyl-11C]acrylamides were synthesized in decay-corrected radiochemical yields up to 81% via palladium-mediated carbonylative cross-coupling of vinyl halides and amines. Starting from 10 ± 0.5 GBq of [11C]carbon monoxide, N-[carbonyl-11C]benzylacrylamide was obtained in 4 min with a specific radioactivity of 330 ± 4 GBq/µmol.

Branched polyethyleneimine (bPEI) was used to modify the surface of Fe3O4 nanoparticles coated with silica layer, and then, it was treated with ethyl iodide to prepare Fe3O4@SiO2@Ethylated-bPEI. In the next step, the yolk–shell structure was gained by selectively etching the SiO2 middle layer. Finally, copper(I) was introduced to the yolk–shell Fe3O4@Ethylated-bPEI and the activity of the catalyst was evaluated for atom transfer radical polymerization (ATRP) of styrene, led to obtain the well-defined polymer with relatively low polydispersity. The toxicity of the residual copper in the polymer product was a limiting issue for applicability of ATRP reactions especially for biological purposes. In this report, the copper content in the polymer was reduced to the excellent value of 1.1 ppm. Moreover, the magnetic isolation, recyclability, and remove the need for an external ligand were other advantages of the synthesized catalyst which makes it suitable for employing in ATRP reactions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42337.

Surface morphology and catalytic properties of electrolytic silver crystals in partial oxidation of ethylene glycol into glyoxal were studied.

Compounds labelled with 11C (β+, t1/2 = 20.4 min) are used in positron emission tomography (PET), which is a quantitative non-invasive molecular imaging technique. It utilizes computerized reconstruction methods to produce time-resolved images of the radioactivity distribution in living subjects.The feasibility of preparing [11C]methyl iodide from [11C]methane and iodine via a single pass through a non-thermal plasma reactor was explored. [11C]Methyl iodide with a specific radioactivity of 412 ± 32 GBq/µmol was obtained in 13 ± 3% decay-corrected radiochemical yield within 6 min via catalytic hydrogenation of [11C]carbon dioxide (24 GBq) and subsequent iodination, induced by electron impact.Labelled ethyl-, propyl- and butyl iodide was synthesized, within 15 min, via palladium-mediated carbonylation using [11C]carbon monoxide. The carbonylation products, labelled carboxylic acids, esters and aldehydes, were reduced to their corresponding alcohols and converted to alkyl iodides. [1-11C]Ethyl iodide was obtained via palladium-mediated carbonylation of methyl iodide with a decay-corrected radiochemical yield of 55 ± 5%. [1-11C]Propyl iodide and [1-11C]butyl iodide were synthesized via the hydroformylation of ethene and propene with decay-corrected radiochemical yields of 58 ± 4% and 34 ± 2%, respectively. [1-11C]Ethyl iodide was obtained with a specific radioactivity of 84 GBq/mmol from 10 GBq of [11C]carbon monoxide. [1-11C]Propyl iodide was synthesized with a specific radioactivity of 270 GBq/mmol from 12 GBq and [1-11C]butyl iodide with 146 GBq/mmol from 8 GBq.Palladium-mediated hydroxycarbonylation of acetylene was used in the synthesis of [1-11C]acrylic acid. The labelled carboxylic acid was converted to its acid chloride and subsequently treated with amine to yield N-[carbonyl-11C]benzylacrylamide. In an alternative method, [carbonyl-11C]acrylamides were synthesized in decay-corrected radiochemical yields up to 81% via palladium-mediated carbonylative cross-coupling of vinyl halides and amines. Starting from 10 ± 0.5 GBq of [11C]carbon monoxide, N-[carbonyl-11C]benzylacrylamide was obtained in 4 min with a specific radioactivity of 330 ± 4 GBq/µmol.

Compounds labelled with 11C (β+, t1/2 = 20.4 min) are used in positron emission tomography (PET), which is a quantitative non-invasive molecular imaging technique. It utilizes computerized reconstruction methods to produce time-resolved images of the radioactivity distribution in living subjects.The feasibility of preparing [11C]methyl iodide from [11C]methane and iodine via a single pass through a non-thermal plasma reactor was explored. [11C]Methyl iodide with a specific radioactivity of 412 ± 32 GBq/µmol was obtained in 13 ± 3% decay-corrected radiochemical yield within 6 min via catalytic hydrogenation of [11C]carbon dioxide (24 GBq) and subsequent iodination, induced by electron impact.Labelled ethyl-, propyl- and butyl iodide was synthesized, within 15 min, via palladium-mediated carbonylation using [11C]carbon monoxide. The carbonylation products, labelled carboxylic acids, esters and aldehydes, were reduced to their corresponding alcohols and converted to alkyl iodides. [1-11C]Ethyl iodide was obtained via palladium-mediated carbonylation of methyl iodide with a decay-corrected radiochemical yield of 55 ± 5%. [1-11C]Propyl iodide and [1-11C]butyl iodide were synthesized via the hydroformylation of ethene and propene with decay-corrected radiochemical yields of 58 ± 4% and 34 ± 2%, respectively. [1-11C]Ethyl iodide was obtained with a specific radioactivity of 84 GBq/mmol from 10 GBq of [11C]carbon monoxide. [1-11C]Propyl iodide was synthesized with a specific radioactivity of 270 GBq/mmol from 12 GBq and [1-11C]butyl iodide with 146 GBq/mmol from 8 GBq.Palladium-mediated hydroxycarbonylation of acetylene was used in the synthesis of [1-11C]acrylic acid. The labelled carboxylic acid was converted to its acid chloride and subsequently treated with amine to yield N-[carbonyl-11C]benzylacrylamide. In an alternative method, [carbonyl-11C]acrylamides were synthesized in decay-corrected radiochemical yields up to 81% via palladium-mediated carbonylative cross-coupling of vinyl halides and amines. Starting from 10 ± 0.5 GBq of [11C]carbon monoxide, N-[carbonyl-11C]benzylacrylamide was obtained in 4 min with a specific radioactivity of 330 ± 4 GBq/µmol.

Ethyl iodide decomposition on the Cu(1 1 1) and Cu(2 2 1) surfaces has been studied using thermal desorption spectroscopy and high resolution electron energy loss spectroscopy. On both surfaces ethyl iodide decomposes to produce ethyl groups and adsorbed iodine atoms. The ethyl groups decompose by β-hydride elimination to desorb as ethylene leaving adsorbed iodine atoms. The kinetics of β-hydride elimination on the Cu(2 2 1) surface are similar to those on the Cu(1 1 0) surface suggesting that the ethyl groups are reacting at the (1 1 0) step edges rather than on the (1 1 1) terraces. Vibrational spectra of the iodine atoms remaining on the surfaces after decomposition of the ethyl groups have been used to probe the iodine binding sites and to corroborate predictions based on density functional theory that the iodine atoms bind to the tops of the step edges. Iodine atoms on Cu(1 1 1) exhibit vibrational modes at 130 and 235 cm−1 that we assign empirically to in-plane and out-of-plane vibrations, respectively, of iodine atoms adsorbed at fcc sites on the (1 1 1) plane. On the stepped Cu(2 2 1) surface an additional peak appears at 80 cm−1 arising from iodine adsorbed at the step edges. The fact that this mode is at a lower frequency than the in-plane mode on the Cu(1 1 1) surface suggests that the iodine atom is adsorbed at the top of the step edge where its motion is unconstrained. These experimental results are consistent with the theoretical prediction that iodine atoms adsorb at the top of the step edges on the Cu(2 2 1) surface.

The reactions of 2H-heptafluoropropane (CF 3 CHFCF 3 , HFC-227ea) with O( 3 P) and H atoms have been studied at high temperatures by using a shock tube technique coupled with atomic resonance absorption spectroscopy. Electronically ground-state oxygen and hydrogen atoms were produced by the laser photolysis of sulfur dioxide and the thermal decomposition of ethyl iodide, respectively. The rate coefficients for the reactions CF 3 -CHFCF 3 + O( 3 P) → i-C 3 F 7 + OH (la) and CF 3 CHFCF 3 + H → i-C 3 F 7 + H 2 (2a) were experimentally determined from the decay of O( 3 P) and H atoms as k 1 a = 10 - 1 0 . 2 7 ′ 0 . 6 7 exp[-(56 ′ 13) kJ mol - 1 /RT] cm 3 molecule - 1 s - 1 (880-1180 K) and k 2 a = 10 - 9 . 1 5 ′ 0 . 6 6 exp[-(63 ′ 14) kJ mol - 1 /RT] cm 3 molecule - 1 s - 1 (1000-1180 K). These results showed that reaction 2a was faster than reaction 1a by a factor of 7-8 over the present experimental temperature range. Both rate coefficients were much smaller than the previous kinetic data for the reactions of propane with O( 3 P) and H atoms, because of an electron-attracting effect of fluorine atoms. To compare the reactivities between isomers, the rate coefficients for the reactions of 1H-heptafluoropropane, CHF 2 CF 2 CF 3 + O( 3 P) → n-C 3 F 7 + OH (3a) and CHF 2 CF 2 CF 3 + H → n-C 3 F 7 + H 2 (4a), were also determined by using the same technique as k 3 a = 10 - 1 0 . 1 3 ′ 0 . 5 2 exp[-(55 ′ 10) kJ mol - 1 /RT] cm 3 molecule - 1 s - 1 (880-1180 K) and k 4 a = 10 - 9 . 4 4 ′ 0 . 3 2 exp[-(57 ′ 7) kJ mol - 1 /RT] cm 3 molecule - 1 s - 1 (1000-1180 K). Furthermore, the rate coefficients for reactions la and 2a were calculated with the transition-state theory (TST). Structural parameters and vibrational frequencies of the reactants and the transition states required for the TST calculation were obtained from the MP2(full)/6-31G(d) ab initio molecular orbital (MO) calculation. The energy barrier, E 0 , was adjusted until the TST rate coefficient most closely matched the observed one. The fitting results of E 0 (1a) = 51 kJ mol - 1 and E 0 (2a) = 41 kJ mol - 1 were in agreement with the G2(MP2) energy barriers, within the expected uncertainty.

The hydrogenation of ethylene on Ni(1 0 0) surface has been studied by TDS. The decrease in the bonding energy with increasing coverage is revealed for both of adsorbed hydrogen and ethylene by the shift of desorption to lower temperatures. Ethane formation is only observed on the preadsorbed hydrogen coverage exceeding 0.5 monolayer (ML), coupled with the growth of H2 shoulder peak at lower temperatures. Further increase of H coverage to saturation reduces the bonding energy of subsequently adsorbed ethylene by 15 kJ/mol and decreases the saturation coverage of ethylene to about one-third on the clean surface. This leads to the shift of ethane desorption from 250 to 220 K and an appearance of additional ethane peak at 180 K. The latter ethane formation coincides with the hydrogenation of surface ethyl species derived from ethyl iodide as a precursor. It indicates that the rate of ethyl formation on the surface would be comparable to that of subsequent hydrogen addition to the surface ethyl species in the hydrogenation of ethylene when the preadsorbed hydrogen coverage approaches 1.0 ML.

We report data from a comprehensive investigation into the photodissociation dynamics of methyl iodide and ethyl iodide at several wavelengths in the range 236-266 nm, within their respective A-bands. The use of non-resonant single-photon ionization at 118.2 nm allows detection and velocity-map imaging of all fragments, regardless of their vibrotational or electronic state. The resulting photofragment kinetic energy and angular distributions and the quantum yields of ground-state and spin-orbit excited iodine fragments are in good agreement with previous studies employing state-selective detection via REMPI. The data are readily rationalised in terms of three competing dissociation mechanisms. The dominant excitation at all wavelengths studied is via a parallel transition to the (3)Q0 state, which either dissociates directly to give an alkyl radical partnered by spin-orbit excited iodine, or undergoes radiationless transfer to the (1)Q1 potential surface, where it dissociates to an alkyl radical partnered by iodine in its electronic ground state. Ground state iodine atoms can also be formed by direct dissociation from the (1)Q1 or (3)Q1 excited states following perpendicular excitation at the shorter and longer wavelength region, respectively, in the current range of interest. The extent of internal excitation of the alkyl fragment varies with dissociation mechanism, and is considerably higher for ethyl fragments from ethyl iodide photolysis than for methyl fragments from methyl iodide photolysis. We discuss the relative advantages and disadvantages of single-photon vacuum-ultraviolet ionization relative to the more widely used REMPI detection schemes, and conclude, in agreement with others, that single-photon ionization is a viable detection method for photofragment imaging studies, particularly when studying large molecules possessing multiple fragmentation channels.

A preliminary study of photophysical and photochemical properties of 9,9′-bianthryl (BA) and 10,10′-dibromo,9,9′-bianthryl (DBrBA) is presented. Dual fluorescence occurring in bianthryl (BA) has been investigated in solvents containing heavy atoms, such as chlorine, bromine and iodine. The presence of heavy atoms reduces strongly the fluorescence lifetimes and the fluorescence quantum yields of BA, the effect is strongest in ethyl iodide, i.e. in the solvent containing the heaviest atom, iodine. On the other hand, it has been found that introduction of two heavy atoms (bromine) into the bianthryl molecule modifies noticeably its fluorescence properties, which indicates existance of an internal heavy atom effect. Again, a reduction of the fluorescence lifetime and the fluorescence quantum yield, compared to the parent molecule, has been observed. On the basis of these observations the mechanism of 1CT ⇒ 3LE intersystem crossing has been discussed. In BA the rate determining process is a reversible spin inversion within the radical pair. In DBrBA where the spin flip is accelerated by the presence of heavy atoms (bromines) the spin-allowed electron transfer 3CT ⇒ 3LE becomes important in the overall intersystem crossing process. It has been found that DBrBA undergoes a photoreduction in the presence of aromatic donors, such as amines, leading finally to BA. Similar reaction seems to be observed in electrochemical measurement. The reduction of DBrBA originates from the primary electron transfer process either photoinduced or electrochemical leading to the free anion radicals of DBrBA.

The effect of H2 plasma pretreatment on the growth rate of films in the catalyst-enhanced chemical vapor deposition of Cu is presented. Cu(I) hexafluoroacetylacetonate-vinyltrimethylsilane [Cu(I)(hfac)(vtms)] and ethyl iodide (C2H5I) were used as a Cu precursor and a chemical source of iodine, respectively. Before adsorbing iodine onto the sputtered Cu seed layer, a pretreatment with H2 plasma promoted the adsorption of iodine. In addition, the Cu film growth rate was almost linearly enhanced with the surface concentration of the iodine adatom. The increment of the surface concentration of the iodine adatom was confirmed by secondary ion mass spectroscopy analysis. The iodine adatoms were not buried during the Cu deposition, but most of them continuously floated out to the film surface. Thus, the iodine on the surface of the Cu seed layer retained its catalytic effect until the film deposition finished. As a result, the H2 plasma pretreatment performed on the Cu seed layer prior to adsorbing iodine enhanc...

The reaction of 20-hydroxyecdysone with methyl or ethyl iodide or allyl bromide in a lithium–ammonia solution results in stereospecific 7α-alkylation to give 7α-methyl-, 7α-ethyl-, and 7α-allyl-14-deoxy-Δ8(14)-20-hydroxyecdysones, respectively. By catalytic hydrogenation (Pd-C/MeOH), the 7α-allyl derivative was converted to 7α-n-propyl-14-deoxy-Δ8(14)-20-hydroxyecdysone.

The hydrogenation of ethylene on Pd(111) is probed using a combination of temperature-programmed desorption (TPD) and reflection−absorption infrared spectroscopy (RAIRS). Ethylene adsorbs on clean Pd(111) in a di-σ configuration but converts to π-bonded species when the surface is presaturated by hydrogen. Ethane is formed with an activation energy of 3.0 ± 0.3 kcal/mol only when Pd(111) is pre-covered by hydrogen and not when ethylene and hydrogen are co-dosed, indicating that ethylene blocks hydrogen adsorption. Experiments performed by grafting ethyl species onto the surface by reaction with ethyl iodide indicate that ethyl species hydrogenate much more rapidly than the overall rate of ethylene hydrogenation, demonstrating that the addition of the first hydrogen atom to adsorbed ethylene to form an ethyl species is the rate-limiting step in the hydrogenation reaction. The adsorption geometry of ethyl iodide is found to depend on dosing conditions. When adsorbed at low exposures at 80 K, the mirror symm...

We studied dehydrogenation reaction of ethylene (C 2 H 4 ) on a Pt(1 1 1) surface using the technique of Cs + reactive ion scattering (RIS). Adsorption of ethyl iodide (C 2 H 5 I) on Pt(1 1 1) was also studied to provide the calibration data. The possible intermediate species in ethylene dehydrogenation to ethylidyne (C–CH 3 ), namely, ethylidene (CH–CH 3 ), vinyl (–CHCH 2 and CCH 2 ), and ethyl species (–CH 2 –CH 3 ), were closely investigated by RIS identification of surface molecules and temperature-programmed kinetic study. The result indicates that the dehydrogenation step occurs through an ethylidene intermediate and that vinyl and ethyl intermediates are not formed.

The reaction of [Pt 2 Me 4 (μ-SMe 2 ) 2 ] with ligand 3-(( S )-PhCHMeNCH)C 4 H 3 S ( 1 ) produced the chiral cyclometallated compound [PtMe{3-(( S )-PhCHMeNCH)C 4 H 2 S}SMe 2 ] ( 2 ) which was characterized structurally. The reactions of 2 with phosphines gave compounds [PtMe{3-(( S )-PhCHMeNCH)C 4 H 2 S}L] (L=PPh 3 ( 3 ), P(2-MeC 6 H 4 ) 3 ( 4 ), Ph 2 PCH 2 CH 2 PPh 2 ( 5 )). The oxidative addition of methyl iodide to compounds 2 and 3 gave two diastereoisomers each of compounds [PtMe 2 I{3-(( S )-PhCHMeNCH)C 4 H 2 S}L] (L=SMe 2 ( 6a / 6a′ ), PPh 3 ( 7a / 7a′ )) in a ratio 2.1:1 and 2.4:1, respectively. Subsequent isomerization gave, in each case, a new pair of diastereoisomers. Compounds 4 and 5 failed to react with methyl iodide, while platinum(II) compounds [PtX{3-(( S )-PhCHMeNCH)C 4 H 2 S}PPh 3 ] (X=I ( 8 ), Br ( 9 )) were obtained in the reactions of 3 with ethyl iodide or benzylbromide.

The reaction of Li(CH2)4Li with [PtCl2(SEt2)2] yielded an unstable complex, probably [{Pt(CH2CH2CH2CH2)(μ-SEt2)}2], 1. Complex 1 reacts with bis(diphenylphosphino)methane, dppm, and forms [{Pt(CH2CH2CH2CH2)(μ-dppm)}2], 2. Complex 2 has been fully characterized using multinuclear NMR and FAB mass spectroscopies and shown to be fluxional in solution. The bright red platinacyclopentane complex [Pt(CH2CH2CH2CH2)(bpy)], 3, in which bpy=2,2′ bipyridyl, has been prepared by reaction of 1 with bpy. In a comparative kinetic study, it was demonstrated that at different temperatures, EtI reacted 2.2–2.6 times faster with the platina(II)cyclopentane complex 3 than with the dimethyl analogue [PtMe2(bpy)].

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.

A variety of aromatic and aliphatic carboxylic acids were smoothly converted into the corresponding nitriles in good yields in a one-pot procedure by treatment with ethyl iodide/K2CO3/18-crown-6, followed by sodium diisobutyl-tert-butoxyaluminium hydride (SDBBA-H), and finally treatment with molecular iodine or 1,3-diiodo-5,5-dimethylhydantoin (DIH), and aqueous ammonia. This method is useful for the conversion of various aromatic and aliphatic carboxylic acids into the corresponding nitriles in a one-pot procedure.

Alkylation of [Mn(CNPh*)5]- with CH3I gives the 1,4-diazabutadien-2-yl in a 30% yield, as established by a single-crystal X-ray diffraction study. The same product can be obtained in poor yield when CH3OSO2CF3 is used as the alkylating agent, and use of ethyl iodide gives the corresponding ethyl It is proposed that the first step in the formation of 2 is alkylation at manganese: transient [Mn(CNPh*)5CH3] is then converted into an iminoacyl complex by isonitrile/alkyl insertion. Insertion of a second isonitrile into the metal−iminoacyl bond leads to the 1,4-diazabutadien-2-yl complex. The addition of free CNPh* to the reaction solution leads to only a modest increase in the yield of 2, but the importance of exogenous isonitrile is supported by the formation in which 1 equiv of CNtBu is coordinated to Mn, when CNtBu is added to a solution of 1- before reaction with CH3I.

Ambient concentrations of four marine-derived halocarbons (methyl iodide, ethyl iodide, bromoform and dibromomethane) and two man-made halocarbons (trichloroethylene and tetrachloroethylene) were measured during western Pacific cruises and east and southeast Asian cruises. Ethyl iodide was detected in the atmosphere for the first time and was identified as an atmospheric iodine source compound. Bromoform concentrations were positively correlated with those of dibromomethane, and methyl iodide showed variations similar to those of ethyl iodide. However, there was no correlation between the bromocarbons and the iodocarbons. The concentrations of methyl iodide and ethyl iodide changed more markedly, possibly owing to higher rates of photodecomposition of iodocarbons.

The reactivity of ethyl iodides on hydrogen predosed Ni ( 100) surfaces has been studied by using temperature programmed desorption (TPD) spectroscopy. The data show that hydrogen coadsorption inhibits the decomposition of ethyl groups at all coverages. Also, at ethyl iodide coverages below saturation, the yields of both ethylene and ethane (the products of β-hydride and reductive elimination reactions respectively) increase equally with hydrogen coadsorption, but near saturation the desorption of ethane increases at the expense of ethylene production. A small amount of ethane is also produced via the hydrogenation of chemisorbed ethylene. This latter reaction occurs at higher temperature, which means that its activation energy is higher than that for the direct hydrogenation of the ethyl species. No coupling or H-D exchange reactions were observed in our experiments.

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 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.

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.

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.

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.

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.

A sequential radical cyclization/intermolecular carbonyl addition process promoted by samarium (II) iodide (SmI 2 ) is reported. Treatment of appropriate haloalkenes with SmI 2 in the presence of a variety of ketones leads to products resulting from cyclization followed by intermolecular addition of the resultant anion to the carbonyl electrophiles. In this study, 2-(allyloxy) ethyl iodide and 2-(allyloxy)-1-iodobenzene were the most thoroughly examined radical precursors. The anion intermediates ultimately derived from these starting materials were trapped with a range of ketones to yield the corresponding heterocyclic derivatives

Oxidative addition of ethyl iodide to PdMe 2 (2,2′-bipyridyl) in (CD 3 ) 2 CO gives the unstable “PdIMe 2 Et(bpy)”, which undergoes reductive elimination to form PdIR(bpy) (R = Me, Et), ethane, and propane. Ethene and palladium metal are also formed, and are attributed to decomposition of PdIEt(bpy) via β-elimination. Similar results are obtained with n-propyl iodide, although a palladium(IV) intermediate was not detected, but CH 2 CHCH 2 X (X = Br, I) and PhCHCHCH 2 Br give isolable complexes fac -PdXMe 2 (CH 2 CHCHR)(L 2 ) (R = H, Ph; L 2 = bpy, phen). The propenyl complexes decompose at ambient temperature to form ethane, a trace of PdXMe(L 2 ), and mixtures of [Pd(η 3 -C 3 H 5 )(L 2 )]X and [Pd(η 3 -C 3 H 5 )(L 2 )]-[Pd(η 3 -C 3 H 5 )X 2 ]; for fac -PdBrMe 2 (CH 2 CHCH 2 )(bpy) the major palladium(II) product is [Pd(η 3 -C 3 H 5 )(bpy)]Br.