Chloroiodomethane Research Articles

Investigating the endocrine disruption effects of four disinfection byproducts on zebrafish estrogen receptor-α

Reports have shown an increase in the use of disinfectants in wastewater treatment plants, prompted by the detection of residual viruses in sewage. However, the release of disinfection byproducts (DBPs) in final effluents has raised concerns about their potential adverse effects, such as endocrine disruption, on aquatic environments. Despite these concerns, few studies have examined the endocrine-disrupting effects of DBPs on fish, which may be vulnerable to DBPs. The aim of this case study was to investigate the endocrine-disrupting properties of four commonly formed DBPs: chloroiodomethane (CIM), dibromochloromethane (DBCM), bromodichloromethane (BDCM), and trichloroacetic acid (TCA) on the estrogen receptor-α in zebrafish (zERα). The results indicated that all four DBPs have high anti-estrogenic activity against zERα; with CIM, BDCM, DBCM, and TCA yielding 80.8%, 78.4%, 49.0%, and 64.1% anti-estrogenic effects on zERα, respectively. Moreover, all DBPs demonstrated negligible estrogenic effects on zERα. Our study sheds new light on the adverse effects of DBPs, particularly the endocrine-disrupting activity of CIM, which, as part of the dihalomethanes group, has received limited research attention in the past. This study shows the molecular interactions in terms of the endocrine disruption of DBP on zERα, warranting further studies to understand the overall impact of fish in affected aquatic ecosystems.

Dichloromethane in the Indian Ocean: Evidence for in-situ production in seawater

We measured partial pressures of CH 2Cl 2 (dichloromethane) and CCl 3F (CFC-11) in air and surface seawater of the Indian and Southern Oceans from November 2009 to January 2010. The excess CH 2Cl 2 saturation anomaly (ΔSA CH2Cl2 > 0) in surface seawater between 10°S and 40°S, which is the corrected value of saturation anomaly after subtracting the effects of summertime sea-surface temperature increase and of summertime decrease of atmospheric CH 2Cl 2 level, provides evidence for in-situ production of CH 2Cl 2. Depth profiles from the South Indian Ocean at 5°S, 20°S and 30°S showed concentration maxima of dihalomethanes (CH 2I 2, CH 2ClI and CH 2Cl 2) and chlorophyll-a in the subsurface layer (20–150 m). Our data suggest that phytoplankton production of dihalomethanes leads to concentration maxima in the subsurface layer and ΔSA CH2Cl2 > 0 in surface seawater between 10°S and 40°S. The average oceanic emission of CH 2Cl 2 derived from the region between 10°S and 40°S in the South Indian Ocean was calculated to be 0.29–0.43 μg m −2 d −1.

Characterization and thermal activation of adducts of Group 4 tetrahalides with 1,2-dialkoxyalkanes

Coordination compounds of general formula MX 4[κ 2-O(R)CH 2CH(R′)OR′′], 2a– i, have been prepared in high yield upon addition of a variety of 1,2-dialkoxyalkanes, ROCH 2CH(R′)OR′′, to MX 4 (M = Ti, X = F, 1a, I, 1b; M = Zr, X = Br, 1c, I, 1d). The new complexes have been characterized by elemental analysis and NMR spectroscopy. The thermal stability of 2 has been studied. Fragmentation of the TiI 4 adducts takes place in chloroform solution at 90 °C: after hydrolysis of the reaction mixtures, MeI and CH 2ICH 2I have been detected from TiI 4[dme] [dme = MeO(CH 2) 2OMe], MeI and Me 2O from TiI 4[MeOCH 2CH(Me)OMe], and MeI, CH 2ICH 2I, Me 2O, CH 2ClI from TiI 4[MeO(CH 2) 2OCH 2Cl]. The diether MeO(CH 2) 2OCH 2Cl is thermally activated also when coordinated to ZrX 4 (X = Br, I): after hydrolysis, MeBr, CH 2BrCH 2Br, O(CH 2CH 2Cl) 2 and Me 2O (X = Br) and MeI, CH 2ClI and CH 2ICH 2I (X = I) have been found, respectively.

Distributions of short-lived iodocarbons and biogenic trace gases in the open ocean and atmosphere in the western North Pacific

Biogenic trace gases, especially halomethanes, which are important with respect to atmospheric chemistry, are released from the ocean and carry halogens to the troposphere and stratosphere. The concentrations of 10 halocarbons and isoprene in seawater were measured during the spring of 2007 in the western North Pacific Ocean (37–43° N, 143–146° E). Sea–air fluxes of CH 3Cl, CH 3Br, CH 2ClI, and CH 2I 2 were also estimated based upon the atmospheric as well as oceanic measurement of these species. Temperature–salinity scatter diagram analyses divided the sampling stations into the Oyashio region, Tsugaru warm current region, and Kuroshio region. Mean (range) concentrations of the gases in the water columns (5–100 m) were 114 (56–150) pmol L − 1 CH 3Cl, 6.9 (4.1–19.4) pmol L − 1 CH 3Br, 1.7 (0.7–2.9) pmol L − 1 CH 3I, 1.9 (0.9–4.1) pmol L − 1 CH 2BrCl, 4.8 (3.2–8.1) pmol L − 1 CH 2Br 2, 1.0 (0.6–1.8) pmol L − 1 CHBrCl 2, 1.2 (0.7–2.0) pmol L − 1 CHBr 2Cl, 10.8 (4.7–24.5) pmol L − 1 CHBr 3, 1.7 (0.7–5.4) pmol L − 1 CH 2ClI, 3.0 (< 0.1–22.2) pmol L − 1 CH 2I 2, and 19.7 (3.8–68.2) pmol L − 1 isoprene. The maximum concentration of isoprene was observed in the Oyashio region, where concentrations of chlorophyll a (maximum: 2.94 µg L − 1 ) were highest in the present study. However, the peaks of CH 3Br, CH 2ClI, and CH 2I 2 were observed in the Tsugaru warm current region, where concentrations of chlorophyll a were not as high (maximum: 0.65 µg L − 1 ). The results of chlorophyll a size fractionation showed a high occurrence of halomethanes in the stations dominated by pico-sized phytoplankton. These results indicate the importance of picoplankton as a possible source of halocarbon production. Chlorophyll b and prasinoxanthin had a statistically significant positive correlation with CH 2I 2 ( r 2 = 0.69 and r 2 = 0.71, respectively) and with CH 2ClI ( r 2 = 0.87 and r 2 = 0.77, respectively). These results suggest that some species of prasinophytes might contribute to CH 2I 2 and CH 2ClI production. For other compounds, there was no peak in the vertical profile in seawater. In the depth profiles, the peak of CH 2ClI was observed above the peak of CH 2I 2; these profiles suggest that a photochemical reaction could yield CH 2ClI from CH 2I 2 in seawater. The mean mixing ratio and range of CH 3Cl, CH 3Br, and CH 2ClI in the air were measured as 548 (524–609), 12.1 (8.6–19.0), and 0.27 (0.03–0.90) pptv, respectively. CH 2I 2 was not detected in the atmosphere (< 1 pptv). The saturation anomaly of CH 3Br was positive at all stations (the sea surface temperature varied from 1.7 °C to 19 °C). The highest mixing ratio of CH 2ClI in air was also observed near the station at which the highest concentration of CH 2ClI was observed in seawater; the sea-to-air fluxes of CH 2ClI and CH 2I 2 were 3.8 and 1.6 nmol m − 2 day − 1 , respectively. These results suggest that the production of CH 2ClI and CH 2I 2 in seawater is an important source of organic iodine compounds in the remote atmosphere.

Study of the upper spin–orbit state of the chloroiodomethane cation by mass-analyzed threshold ionization

The vibrational spectrum of CH 2ClI + in the upper spin–orbit state was obtained by one-photon mass-analyzed threshold ionization (MATI) spectrometry. The accurate ionization energy of the upper spin–orbit state was determined to be 10.3045 ± 0.0006 eV. The energy gap between the upper and lower spin–orbit states was 0.5539 ± 0.0012 eV. The frequency of the Cl–C–I bending mode was found to be most affected by the spin–orbit interaction. This suggests that the avoided crossing between the lower and upper spin–orbit states occurs along a direction close to the Cl–C–I bending coordinate.

Synthesis and X-ray crystal structure of a new μ-hydroxo dinuclear cobalt complex containing one cis-β folded and one planar salen moiety

The reduction of [Co(III)(tmsalen)(py) 2] + with NaBH 4/PdCl 2 and the successive oxidative addition of CH 2ClI, carried out in neutral methanolic solution and followed by the addition of NaOH, afford a new dinuclear complex. The molecular structure reveals that it is formed by an octahedral [Co(tmsalen)(py)(OH)] unit connected to a β-folded [Co(tmsalenCH 2)] + fragment, in such a way that the latter metal completes the coordination sphere with the hydroxo group and a tmsalen oxygen from the former unit.

A Dramatic Spin–Orbit Effect Observed in the Vibrational Frequencies of the Chloroiodomethane Cation

Several theoretical studies have suggested that a spin–orbitinduced isomer may be found for a molecule of the as-yetunknow superheavy element 118, that is, (118)F4, [1] but there have been no reports of an experimentally observed molecule for which the inclusion of spin–orbit effects is essential for the correct identification of the ground state structure. We report here a molecular ion, [CH2ClI] , for which spin–orbit interactions are crucial for the identification of the structure and vibrational frequencies of the correct ground state. Theoretically, the spin–orbit interaction is part of the relativistic effect. The importance of relativity for the description of heavy atoms is well recognized. Scalar relativistic effects are routinely included in electronic-structure calculations of molecules containing heavy elements through the use of relativistic effective core potentials (RECP), but spin–orbit interactions are usually omitted when deriving optimized structures partly because of the assumption that their influence on the molecular structures is negligible and partly due to computational difficulties. Even when spin–orbit terms are available in RECPs, the usual treatment involves perturbational inclusion of these terms after the variational determination of orbitals and structures. Quantum chemical calculations employing RECPs and spin– orbit operators from the start have been available for some time. The spin–orbit density functional theory (DFT) method available in NWChem is particularly useful for the present purpose of demonstrating spin–orbit effects on geometries since the geometry can be optimized with both electron correlations and spin–orbit interactions included. We have been investigating the reactivity of mixed dihalomethane cations for some time. Hence, we have recorded the vibrational spectra of the cations by massanalyzed threshold ionization (MATI) spectrometry. Figure 1 shows the MATI spectrum of CH2ClI recorded by monitoring [CH2 ClI] in the electronic ground state. The most intense peak at around 78644 cm 1 corresponds to the 0–0 band. The distance of each peak from the 0–0 band in this spectrum corresponds to the vibrational frequency of the cation. CH2ClI has nine nondegenerate normal modes: modes 1–6, with a’ symmetry, and modes 7–9, with a’’ symmetry. All the fundamentals and overtones of the totally symmetric modes, a’, are dipole-allowed, while only the even-numbered overtones of the a’’modes are allowed. Utilizing the selection rule and the frequencies in the neutral species, plausible assignments can be made for the prominent peaks; these are listed in Table 1. Modes 2 and 3 are due to CH2 motion, modes 4 and 5 are C Cl and C I stretchings, respectively, and mode 6 is I C Cl bending. Other peaks in the spectrum are due to overtones and combinations. Our normal routine is to perform quantum chemical calculations for the vibrational frequencies, isotope shifts, and Franck–Condon factors to confirm, improve, or revise the phenomenological assignments. In particular, results from the DFT/B3LYP calculations have been found to be adequate in most cases. When we performed DFT/B3LYP calculations for [CH2ClI] + with Gaussian98, using a well-knownRECP for iodine such as LanL2DZ, we always obtained two distinct stationary states, A’ and A’’, formed by removal of an electron from in-plane and out-of-plane iodine nonbonding orbitals, respectively. Even though their energies are nearly the same, their geometries are noticeably different because of the partial antibonding characteristics contained in essentially iodine nonbonding orbitals. The vibrational frequencies in the two states are also noticeably different, suggesting that the observed spectrum would be a superposition of two spectra. The fact that a rather straightforward phenomenological assignment of the MATI spectrum was possible is not compatible with the calculated results. Moreover, the experimental frequencies could not be correlated with the calculated results with the accuracy expected for the DFT/B3LYP results ( 15 cm ). We thought that neglecting the spin–orbit effect could be one possible cause of this discrepancy, and we therefore performed the spin–orbit DFT calculations implemented in NWChem for neutral and cationic CH2ClI in the electronic ground states using RECPs with the effective spin– [*] M. Lee, Prof. M. S. Kim National Creative Research Center for Control of Reaction Dynamics and School of Chemistry, Seoul National University Seoul 151-742 (Korea) Fax: (+82)2-889-1568 E-mail: myungsoo@plaza.snu.ac.kr

Production of free and organic iodine by Roseovarius spp.

Two strains of iodine-producing bacteria were isolated from marine samples. 16S rRNA gene sequences indicated the strains were most closely related to Roseovarius tolerans, and phylogenetic analysis indicated both belong to the same genus. 5 mM iodide inhibited the growth of strain 2S5-2 almost completely, and of strain S6V slightly. Both strains produced free iodine and organic iodine from iodide. CH 2I 2, CHI 3 and CH 2ClI were the main organic iodines produced by strain 2S5-2, and CHI 3 and CH 2I 2 by strain S6V. Experiments using cells and spent media suggested that the organic iodines were produced from the compounds released or contained in the media and cells were necessary for the considerable production of CH 2I 2 and CH 2ClI, though CHI 3 was produced by spent media with H 2O 2 or free iodine.

Depth profiles of volatile halogenated hydrocarbons in seawater in the Bay of Bengal

Measurements were made of bromocarbons (CHBr 3 and CH 2Br 2), iodocarbons (CH 2I 2 and CH 2ClI), and dimethylsulfide (DMS, CH 3SCH 3) in seawater collected from the Bay of Bengal under tropical stratified conditions. These compounds showed different depth profiles, characteristic of each group. CH 2I 2 and CH 2ClI showed very similar depth profiles to chlorophyll- a, suggesting their production by phytoplankton followed by rapid decay in seawater. The CH 2I 2 maximum at a depth a little below the CH 2ClI maximum was consistent with its more significant photolytic decay. The bromocarbons were less localized in their distributions than were the iodocarbons, suggesting their longer residence time in seawater after their release from phytoplankton. Both of these profiles were different from the pattern of DMS, which had its maxima above the chlorophyll- a maximum layer near the surface.

Rotational alignment from the Sr( [formula omitted])+CH 2ClI chemiluminescent reaction

The rotational alignment of the product SrI( B 2 Σ + ) is obtained from Sr( 3 P J )+CH 2ClI chemiluminescence. The experiment is carried out under beam–gas conditions. Furthermore, by simulating the chemiluminescent spectrum of SrI, the electronic state branching ratio and the product vibrational state population have been roughly estimated. According to statistical theory, the branching ratio is obtained, which is in good agreement with the experimental result.

The distribution of man-made and naturally produced halocarbons in a double layer flow strait system

The Bosphorus Strait, which connects the Black Sea and Mediterranean Sea via the Marmara Sea, is characterised by two distinct water masses. The upper layer consists of low density Black Sea water (sigma-t 10–11) flowing southward, and it is underlain by high density water (sigma- t >28) of Mediterranean origin flowing northward. The sharp density gradient between the two layers is due to the difference in salinities. Here we report measurements on a suite of low molecular weight halocarbons together with basic hydrographic parameters in the strait. Concentrations of the transient tracers chlorofluorocarbons CFC-11 (CFCl 3), CFC-113 (CCl 2FCCIF 2) and carbon tetrachloride (CCl 4) were highest in the Cold Intermediate Black Sea Water (CIBSW), which is formed in the Black Sea during winter. This layer disappeared within the contraction region of the Bosphorus where a hydraulic jump occurs. The Marmara Sea deep water at the entrance to the Bosphorus Strait carried low amounts of CFCs indicating an equilibrium with the atmosphere 6–11 years earlier. Varying amounts of other halocarbons such as chloroform (CHCl 3), dibromomethane (CH 2Br 2), methyl iodide (CH 3I) and chloro-iodomethane (CH 2ClI) could be used for the identification of water masses of different origin. Around the Bosphorus-Marmara Junction (BMJ) in the Istanbul area, the upper water layer contained elevated levels of most of the halocarbons. This is attributed not only to contamination but also to natural production in the productive eutrophic waters of the region. Methyl iodide and chloro-iodomethane showed elevated concentrations of 0.7–0.9 ng/l and 0.4–0.6 ng/l, respectively, in the upper water layer of the BMJ region, and also in near-bottom water at the northern exit of Bosphorus (0.2 and 0.1 ng/l, respectively). Chloroform (23 ng/l) and dibromomethane (10 ng/l) were also found within the pycnocline in the BMJ region and could be traced in a plume stretching northward along the pycnocline.

Determination of Henry's Law constants for a suite of naturally occurring halogenated methanes in seawater

Henry's Law constants have been measured for a suite of naturally-occurring halogenated methanes (CH 3Cl, CH 3I, CH 2Br 2, CHBr 2Cl, CHBrCl 2, CHBr 3, CH 2I 2 and CH 2ClI) in seawater. The procedure involved equilibrating a gas stream with a temperature-controlled column of seawater containing the compounds of interest at nanomolar concentrations. Temperature dependencies of the constants are reported between 0 and 20°C.

The involvement of hydrogen peroxide in the production of volatile halogenated compounds by Meristiella gelidium

The production of volatile halogenated compounds (VHCs) by the red alga Meristiella gelidium has been studied in batch culture. Production of CHBr 3, CHBr 2Cl, CHBrCl 2, CHCl 3, HCClCCl 2, CH 2Br 2, CH 2I 2, CH 2ClI, C 4H 9I and MeI was found. The most common VHCs produced were CHBr3 and CH 2I 2 with a formation rate of 100 and 12 pmol g −1 fr. wt after 1 hr. Normally the production rate of VHCs slowed down after approximately 1–2 hr. Addition of 1 mM H 2O 2 increased the production of HCClCCl 2, CHBr 3, CHBr 2Cl, CHBrCl 2 and CHCl 3 by between 50 (CHBr 3) and 500% (HCClCCl 2). The same compounds also showed a decreased production after the addition of 1 mM NaN 3. This suggests the importance of peroxidases in the production of some of the VHCs by macroalgae. The iodine containing VHCs did not increase with addition of H 2O 2. We propose that the bromo-chloro VHCs are formed as a result of H 2O 2 production and subsequent H 2O 2 scavenging activities by peroxidases.

Biogenic volatile organoiodine and organobromine compounds released from polar macroalgae

During September 1992 three different species of macroalgae ( Laminaria saccharina, Desmarestia aculeata and Fucus distichus) were collected on Spitsbergen. These macroalgae were cultivated in incubation vessels on Spitsbergen under polar conditions and the releasing rates of volatile organoiodine and organobromine compounds were determined by using a purge and trap system for the isolation of the compounds followed by a gas chromatographic separation with an electron capture detection. Using this method the releasing rates of CH 3I, CH 2ClI, CH 3CH 2CH 2I, CH 3CHICH 3, CH 2I 2, CHBrCl 2, CHBr 2Cl, CH 2Br 2, and CHBr 3 were determined. The three species of macroalgae showed distinct differences in the releasing rates for the various substances. Laminaria saccharina was found to produce the highest amounts of bromoform and dibromomethane with average releasing rates of about 72 and 8 ng per g of alga (wet weight) and day, respectively. This species also showed the highest releasing rate for diiodomethane with about 4 ng g −1 d −1, whereas the average releasing rates for methyl iodide, 1-propyl iodide, and 2-propyl iodide were highest for Fucus distichus with 0.8, 0.15, and 0.8 ng g −1 d −1, respectively. These results show that macroalgae are responsible for part of the total production of volatile iodinated and brominated organic substances in the polar coastal seawater and therefore for their corresponding atmospheric concentration, which plays an important role in atmospheric chemistry. In addition, it could be shown that every species of macroalgae has its own releasing pattern of iodinated compounds, which can possibly be used in the future for source identification.

Synthesis, structure, and reactivity of ylide rhodium(I) and rhodium (III) complexes

The olefin(ylide) rhodium(I) complexes [(L)( iPr 3PCH 2)Rh(Cl] 2 ( 3: L = C 8H 14; 4: L = C 2H 4) have been prepared from [(L) 2RhCl] 2 ( 1, 2) and CH 2P iPr 3 in almost quantitative yield. Upon treatment of 3 and 4 with LiC 5H 5, the half-sandwich type compounds [C 5H 5Rh(CH 2P iPr 3)(L)] ( 5, 6) are obtained. Compound 5 (L = C 8H 14) reacts with carbon monoxide to give [C 5H 5Rh(CH 2P iPr 3)(CO)] ( 7) and with iodine to give [C 5H 5Rh(CH 2P iPr 3)I 2] ( 8). Displacement of the olefin ligand also occurs upon treatment of 5 with CH 3I, CH 2I 2 and CH 2ClI, leading to the formation of [C 5H 5RhCH 2X(CH 2P iPr 3)I] 9: X = H; 10: X = I; 11: X = Cl). The bis(ylide) rhodium(III) complexes [C 5H 5Rh(CH 2PR 3)(CH 2P iPr 3)I]I ( 12– 14), [C 5H 5Rh(CH 2P iPr 3)(CH 2AsPh 3)I]I ( 5) and [C 5H 5Rh(CH 2P iPr 3)(CH 2NEt 3)I]I ( 16) are obtained by nucleophilic substitution from 10 upon treatment with Pr 3, AsPh 3 and NEt 3, respectively. Reaction of 7 with CH 3I or CD 3I give a mixture of 8 and [C 5H 5RhCX 3(CH 2P iPr 3)(CO)I ( 17a: X = H; 17b: X = D). I contrast, treatment of 7 with dimethylsulfate gives only [C 5H 5RhCH 3(CH 2P iPr 3)-(CO)]SO 4Me ( 17c). The X-ray crystal structure of 17c has been determined. Compound 17c reacts with P iPr 3 to give the acetyl(ylide) rhodium(III) complex [C 5H 5RhCOCH 3(CH 2P iPr 3(P iPr 3)]SO 4Me ( 18).

Metallkomplexe mit verbrückenden dimethylphosphido-liganden: IV. Additions- und insertionsreaktionen von [C 5H 5Co(μ-PMe 2)] 2 mit schwefel, selen un tellur

The complex [C 5H 5Co(μ-PMe 2)] 2 reacts with sulphur, selenium and tellurium at room temperature to give the compounds [(C 5H 5Co) 2(μ-PMe 2) 2(μ-E)] (IV: E = S; VI: E = Se; VIII: E = Te) and [(C 5H 5Co) 2(μ-PMe 2)(μ-EPMe 2)] (V: E = S; VII: E = Se). By using grey selenium, compound VI is predominantly obtained, whereas with the red form of Se, compound VII is the main product. The nucleophilic behaviour of the bridging-chalcogen atoms in the dinuclear complexes IV, VI and VIII is characterised by their reaction with CF 3CO 2H/NH 4PF 6, CH 3I, CH 2ClI and C 5H 5Mn(CO) 2THF from which the compounds [(C 5H 5Co) 2(μ-PMe 2) 2(μ-EH)]PF 6, [(C 5H 5Co) 2(μ-PMe 2) 2(μ-ECH 3)]I, [(C 5H 5Co) 2(μ-PMe 2) 2(μ-SeCH 2Cl)]PF 6 and [(C 5H 5Co) 2(μ-PMe 2) 2(μ-EMn(CO) 2C 5H 5)] are obtained. The proposed structure of these complexes is discussed on the basis of their 1H and 31P NMR spectra.

Haloalkyl complexes of the transition metals: IV. The formation of a cationic ylide complex of platinum(II) from a chloromethylplatinum(II) complex and the crystal structures of cis-[Pt(CH 2PPh 3)X(PPh 3) 2]I (X = Cl or I)

The reactions of Pt(PPH 3) 4 and Pt(C 2H 4)(PPh 3) 2 with CH 2ClI have been investigated. The product of the reaction of Pt(PPh 3) 4 with CH 2ClI is the cationic ylide complex cis-[Pt(CH 2PPh 3)Cl(PPh 3)2][I], whereas the reaction of Pt(C 2H 4)-(PPh 3) 2 gives the oxidative addition product Pt(CH 2Cl)I(PPh 3) 2. Reaction of cis- or trans-Pt(CH 2Cl)I(PPh 3) 2] with PPh 3 gives the complex cis-[Pt(CH 2PPh 3)-Cl(PPh 3) 2][I]. The structures of the complexes cis-[Pt(CH 2PPh 3X(PPh 3) 2][I] (where X = Cl or I) have been determined by X-ray crystallography. Both complexes crystalize in the monoclinic space group P2 1/ n. For X = Cl a 1388.6(7), b 2026.7(10), c 1823.9(9) pm, β 96.51(2)° and R converged to 0.075 for 3542 observed reflections; structural parameters Pt-Cl 240(1), Pt-C(3) 212(2), Pt-P(2) ( trans to Cl) 235(1) and Pt-P(1) ( trans to CH 2PPh 3) 233(1) pm; Cl-Pt-C(3) 86.9(5), C(3)-Pt-P(2) 91.8(5), P(2)-Pt-P(1) 97.0(2) and P(1)-Pt-Cl 85.1(2)°. For X = I, a 1379.4(7), b 2044.4(10), c 1840.0(9) pm, β 96.09(2)° and R converged to 0.071 for 4333 observed reflections; structural parameters Pt-I 266(1), Pt-C(3) 212(2), Pt-P(2) ( trans to I) 226(1) and Pt-P(1) ( trans to CH 2PPh 3 233(1) pm; I-Pt-C(3) 87.2(5), C(3)-Pt-P(2) 91.5(5), P(2)-Pt-P(1) 96.5(2) and P(1)-Pt-I 85.6(1)°. Some other complexes of the type cis-[Pt(CH 2PPh 3)X(PPh 3) 2]Y are also described.

UV angle-resolved photoelectron spectra of mixed methylene dihalides using synchrotron radiation

Photoelectron spectra for the dihalomethanes CH 2BrCl, CH 2ClI and CH 2Br 2 have been recorded with photons in the energy range 19–115 eV using Daresbury Laboratory Synchroton Radiation Source. Ionization energies have been measured for all valence falling within this energy including Br 3d and I 4d orbitals. Asymmetry parameters have been measured for all intense ionization processes and characteristic Cooper minima observed for halogen lone pair orbitals. For CH 2ClI lone pair orbital β spectra show strong evidence of mixed halogen character although a similar situation is not observed for CH 2BrCl. Partial photoionization cross sections are tabulated for the observed ionization processes. Detailed spectra are presented for the molecule CH 2ClI since this appears to be the first photoelectron study of this molecule.

Competition between reactive and inelastic processes involving I 2(D 1Σ +u)

The removal of I 2(D 1Σ + u) by CH 3Cl, following optical excitation at 193 and 185 nm has been studied by monitoring flourescence throughout the region 200–500 nm. It is observed that quenching of this state occurs both by reaction to form CH 3I and CH 2ClI and by inelastic collisions to the lowest ion-pair state ( 3Π 2g).

Haloalkyl complexes of the transition metals : II. Some new chloromethyl and methoxymethyl complexes of manganese, rhenium and ruthenium

The reactions of Na[Mn(CO) 5] or Na[Mn(CO) 4(PPh 3)] with CH 2ClI yield the new chloromethyl complexes Mn(CO) 5CH 2Cl and Mn(CO) 4(PPh 3)CH 2Cl. Reaction of Na[Re(CO) 5] or Na[CpRu(CO) 2] with ClCH 2OMe yields Re(CO) 5CH 2Cl and CpRu(CO) 2CH 2Cl respectively, in addition to the corresponding methoxymethyl complexes (Cp = η 5-C 5H 5). Reaction of CpRu(CO) 2CH 2OMe with HCl yields the corresponding chloromethyl complex.