Evolution Of Ethane Research Articles

Zur Dekarbonisierung N‐Heterocyclischer Carbene (NHCs): Die einfachen Alan‐Addukte (NHC) ⋅ AlR3 (R=H, Me, Et)

AbstractDie Reaktion des Amin‐stabilisierten Alans (NMe3) ⋅ AlH3 1 mit dem Rückgrat‐gesättigten N‐heterocyclischen Carben (NHC) SIDipp (SIDipp=1,3‐Bis‐{2,6‐di‐iso‐propyl‐phenyl}‐imidazolidin‐2‐yliden) bei 0 °C ergab das NHC‐stabilisierte Alan‐Addukt (SIDipp) ⋅ AlH3 2. Erhöhte Temperaturen oder verlängerte Reaktionszeiten bei Raumtemperatur führten zum Produkt einer Ringerweiterungs‐Reaktion (RER) des NHCs, (NMe3) ⋅ AlH(RER‐SIDippH2), 3 ⋅ (NMe3). Die anschließende Reaktionen mit den sterisch weniger anspruchsvollen NHCs (IMeMe {=1,3,4,5‐Tetramethyl‐imidazolin‐2‐yliden}, IiPrMe {=1,3‐Di‐iso‐propyl‐4,5‐dimethyl‐imidazolin‐2‐yliden} und IiPr {=1,3‐Di‐iso‐propyl‐imidazolin‐2‐yliden}) lieferten die NHC‐stabilisierten RER‐Produkte (NHC) ⋅ AlH(RER‐SIDippH2) 3 ⋅ (NHC) (NHC=IMeMe, IiPrMe, IiPr), während mit den sterisch anspruchsvolleren NHCs IDipp (=1,3‐Bis‐{2,6‐di‐iso‐propyl‐phenyl}‐imidazolin‐2‐yliden), SIDipp und ItBu (=1,3‐Di‐tert‐butyl‐imidazolin‐2‐yliden) keine Reaktion beobachtet wurde. Die Verbindungen 3 ⋅ (NHC) wurden ebenfalls ausgehend von (SIDipp) ⋅ AlH3 2 und NHC bei Raumtemperatur erhalten. Das Erhitzen von Lösungen von (SIDipp) ⋅ AlH3 2 ohne zusätzliche Base auf 95 °C führte unter Verlust von Ethen zu einer Dekarbonisierung des NHCs und somit zur Substitution des Carben‐Kohlenstoffatoms durch Aluminiumhydrid. Die anschließende Dimerisierung ergab cis‐[AlH{μ‐N(Dipp)CH2CH2N(Dipp)}]2 4_dimer. Das Erhitzen von Lösungen der NHC‐stabilisierten Aluminiumalkyle (SIDipp) ⋅ AlR3 2R (R=Me, Et) auf 145 °C führte stattdessen unter Freisetzung von Ethen zur vollständigen Spaltung des NHC‐Grundgerüstes und Isolierung der Dialkylaluminium(III)‐Amidinate {DippNC(R)NDipp}AlR2 5R (R=Me, Et).

How to Decarbonize N-Heterocyclic Carbenes (NHCs): The simple Alane Adducts (NHC) ⋅ AlR3 (R=H, Me, Et).

The reaction of the amine-stabilized alane (NMe3) ⋅ AlH3 1 with the backbone-saturated N-heterocyclic carbene (NHC) SIDipp (SIDipp=1,3-bis-{2,6-di-iso-propyl-phenyl}-imidazolidin-2-ylidene) at 0 °C yielded the NHC alane adduct (SIDipp) ⋅ AlH3 2. Reaction at elevated temperatures or prolonged reaction at room temperature gave the product of a ring expansion reaction (RER) of the NHC, (NMe3) ⋅ AlH(RER-SIDippH2) 3 ⋅ (NMe3). Subsequent reaction of the latter with sterically less hindered NHCs (IMeMe {=1,3,4,5-tetramethyl-imidazolin-2-ylidene}, IiPrMe {=1,3-di-iso-propyl-4,5-dimethyl-imidazolin-2-ylidene}, and IiPr {=1,3-di-iso-propyl-imidazolin-2-ylidene}) afforded the NHC-stabilized RER-products (NHC) ⋅ AlH(RER-SIDippH2) 3 ⋅ (NHC) (NHC=IMeMe, IiPrMe, IiPr), while no reaction was observed with the sterically more demanding NHCs IDipp (=1,3-bis-{2,6-di-iso-propyl-phenyl}-imidazolin-2-ylidene), SIDipp and ItBu (=1,3-di-tert-butyl-imidazolin-2-ylidene). The compounds 3 ⋅ (NHC) were also obtained starting from (SIDipp) ⋅ AlH3 2 and NHC at room temperature. Heating solutions of (SIDipp) ⋅ AlH3 2 without additional base to 95 °C resulted in decarbonization of the NHC and substitution of the carbene carbon atom with aluminum hydride under loss of ethene. Subsequent dimerization afforded cis-[AlH{μ-N(Dipp)CH2CH2N(Dipp)}]2 4_dimer. Heating solutions of the NHC-ligated aluminum alkyls (SIDipp) ⋅ AlR3 2R (R=Me, Et) to 145 °C instead led to complete scission of the NHC backbone with evolution of ethene and isolation of the dialkylaluminium(III) amidinates {DippNC(R)NDipp}AlR2 5R (R=Me, Et).

In Situ Grignard Metalation Method for the Synthesis of Hauser Bases.

The in situ Grignard Metalation Method (iGMM) is a straightforward one‐pot procedure to quickly produce multigram amounts of Hauser bases R2N‐MgBr which are valuable and vastly used metalation reagents and novel electrolytes for magnesium batteries. During addition of bromoethane to a suspension of Mg metal and secondary amine at room temperature in an ethereal solvent, a smooth reaction yields R2N‐MgBr under evolution of ethane within a few hours. A Schlenk equilibrium is operative, interconverting the Hauser bases into their solvated homoleptic congeners Mg(NR2)2 and MgBr2 depending on the solvent. Scope and preconditions are studied, and side reactions limiting the yield have been investigated. DOSY NMR experiments and X‐ray crystal structures of characteristic examples clarify aggregation in solution and the solid state.

Characterization of Re-Mo/ZSM-5 catalysts: How Re improves the performance of Mo in the methane dehydroaromatization reaction

In this study, the promoting effect of rhenium addition as a co-dopant on Mo/ZSM-5 catalysts system has been analysed. Hence, bimetallic (Re-Mo/ZSM-5) catalysts have been synthesized using a sequential impregnation methodology. The catalytic performance for direct aromatization of methane reaction has been determined and correlated with their physical and chemical state combining multiple characterization techniques. An important synergy between Mo and Re, affected by the sequential impregnation, has been observed. Thus, Re1-Mo4/ZSM-5 in which Re has been incorporated first shows notably higher aromatic yields and stability against deactivation. Characterization results suggest that catalytic enhancement is due to the important effect of Re presence in close interaction with Mo. Improved evolution of ethane through C-C coupling would be correlated to this catalytic performance. As we discuss, Mo nature and location in the bimetallic systems are strongly conditioned by Re and the impregnation sequence and favours such intermediate step.

Advanced remediation using nanosized zero-valent iron and electrical current in situ − A comparison with conventional remediation using nanosized zero-valent iron alone

This study presents an advance on the standard in situ reductive remediation technique using nanosized zero valent iron (NZVI). The initial process used a conventional form of NZVI, NANOFER 25S (NANO IRON, s.r.o.), at a site contaminated with chlorinated hydrocarbons (CHC) in 2014. In 2018, levels of contamination at the site were still too high; hence, a second remediation intervention was performed using a cheaper form of NZVI, NANOFER STAR DC (NANO IRON, s.r.o.), accompanied with application of an electrical current (DC). The physical-chemical parameters at the site showed moderate reductive conditions for both techniques. While remediation with NANOFER 25S showed a continuous decrease in NZVI activity over time, application of NANOFER STAR DC + DC resulted in a long-term reductive effect, observable as a persistent decrease in CHC concentration and evolution of ethene and ethane dechlorination products. NZVI in the STAR DC + DC was still active after around 200 days. Final efficiency of the STAR DC + DC method was calculated at 3.7 times higher than the conventional technique using NANOFER 25S only. Laboratory-scale experiments confirmed the field observations, indicating the significantly elevated effectivity of STAR DC + DC.

Reduction of chlorinated hydrocarbons using nano zero-valent iron supported with an electric field. Characterization of electrochemical processes and thermodynamic stability

Electric field assisted remediation using nano iron has shown outstanding results as well as economic benefits during pilot applications (Černíková et al., 2020). This method is based on donating electrons to the zero-valent iron that possess an inherently strong reductive capacity. The reduction of chlorinated hydrocarbons may be characterized by a decrease in contaminants or better still by the evolution of ethene and ethane originating from the reduction of chlorinated ethenes. The evolution of ethene and ethane was observed predominantly in the vicinity of the anode despite reduction processes being expected near the cathode – the electron donor. The reduction near the anode occurred due to dissolved Fe2+ ions, whose presence was suggested by a Pourbaix diagram that combines Eh/pH values to characterize electrochemical stabilities between different species. No products of dechlorination were observed in the area of the cathode due to presence of oxidized Fe in the form of Fe3+ or Fe(OH)4-. The experimental work described in this research provides a deeper view of the processes of electrochemical reductive dechlorination using zero-valent iron and DC. It also showed an increase in the efficiency compared to the method using zero-valent iron only.

Electron beam irradiation of dimethyl-(acetylacetonate) gold(III) adsorbed onto solid substrates

Electron beam induced deposition of organometallic precursors has emerged as an effective and versatile method for creating two-dimensional and three-dimensional metal-containing nanostructures. However, to improve the properties and optimize the chemical composition of nanostructures deposited in this way, the electron stimulated decomposition of the organometallic precursors must be better understood. To address this issue, we have employed an ultrahigh vacuum-surface science approach to study the electron induced reactions of dimethyl-(acetylacetonate) gold(III) [AuIII(acac)Me2] adsorbed onto solid substrates. Using thin molecular films adsorbed onto cooled substrates, surface reactions, reaction kinetics, and gas phase products were studied in the incident energy regime between 40 and 1500 eV using a combination of x-ray photoelectron spectroscopy (XPS), reflection absorption infrared spectroscopy (RAIRS), and mass spectrometry (MS). XPS and RAIRS data indicate that electron irradiation of AuIII(acac)Me2 is accompanied by the reduction in AuIII to a metallic Au0 species embedded in a dehydrogenated carbon matrix, while MS reveals the concomitant evolution of methane, ethane, carbon monoxide, and hydrogen. The electron stimulated decomposition of AuIII(acac)Me2 is first-order with respect to the surface coverage of the organometallic precursor, and exhibits a rate constant that is proportional to the electron flux. At an incident electron energy of 520 eV, the total reaction cross section was ≈3.6×10−16 cm2. As a function of the incident electron energy, the maximum deposition yield was observed at ≈175 eV. The structure of discrete Au-containing deposits formed at room temperature by rastering an electron beam across a highly ordered pyrolytic graphite substrate in the presence of a constant partial pressure of AuIII(acac)Me2 was also investigated by atomic force microscopy.

Site-blocking effects of preadsorbed H on Pt(1 1 1) probed by 1,3-butadiene adsorption and reaction

The influence of hydrogen coadsorption on hydrocarbon chemistry on transition metal surfaces is a key aspect to an improved understanding of catalytic selective hydrogenation. We have investigated the effects of H preadsorption on adsorption and reaction of 1,3-butadiene (H 2C CHCH CH 2, C 4H 6) on Pt(1 1 1) surfaces by using temperature-programmed desorption (TPD) and Auger electron spectroscopy (AES). Preadsorbed hydrogen adatoms decrease the amount of 1,3-butadiene chemisorbed on the surface and chemisorption is completely blocked by the hydrogen monolayer (saturation) coverage ( θ H = 0.92 ML). No hydrogenation products of reactions between coadsorbed H adatoms and 1,3-butadiene were observed to desorb in TPD experiments over the range of θ H investigated ( θ H = 0.6–0.9 ML). This is in strong contrast to the copious evolution of ethane (CH 3CH 3, C 2H 6) from coadsorbed hydrogen and ethylene (CH 2 CH 2, C 2H 4) on Pt(1 1 1). Hydrogen adatoms effectively (in a 1:1 stoichiometry) remove sites from interaction with chemisorbed 1,3-butadiene, but do not affect adjacent sites. The adsorption energy of coadsorbed 1,3-butadiene is not affected by the presence of hydrogen on Pt(1 1 1). The chemisorbed 1,3-butadiene on hydrogen preadsorbed Pt(1 1 1) completely dehydrogenates to H 2 and surface carbon upon heating without any molecular desorption detected, which is identical to that observed on clean Pt(1 1 1). In addition to revealing aspects of site blocking that should have broad implications for hydrogen coadsorption with hydrocarbon molecules on transition metal surfaces in general, these results also provide additional basic information on the surface science of selective catalytic hydrogenation of butadiene in butadiene–butene mixtures.

Reactivity of SiMe2H Substituents in Permethylated Titanocene Complexes: Dehydrocoupling and Ethene Hydrosilylation

The complex [TiCl2{η5-C5Me4(SiMe2H)}2] (3) was prepared by reacting the lithium salt of 2,3,4,5-tetramethyl-1-(dimethylsilyl)cyclopenta-2,4-diene (1) with [TiCl3(THF)3] followed by chlorination of the formed [TiCl{η5-C5Me4(SiMe2H)}2] (2) with PbCl2. The reduction of 3 with excess magnesium in THF in the presence of excess bis(trimethylsilyl)ethyne (btmse) afforded the bivalent metal ansa disilylene complex with π-coordinated btmse [Ti{η5-C5Me4(SiMe2)}2(η2-btmse)] (4). The dehydrocoupling of the SiMe2H groups was accompanied by hydrogen transfer to the free btmse. Analogous reduction of 3 with magnesium in the presence of ethene gave a mixture of titanocene [Ti{η5-C5Me4(SiMe2Et)}2] (5) and its ethene complex [Ti{η5-C5Me4(SiMe2Et)}2(η2-C2H4)] (6). The latter complex is however unstable in this mixture and rearranges with evolution of ethane to [Ti{η5-C5Me4(SiMe2Et)}{η5:η2-C5Me4(SiMe2CH═CH2)}] (7), which has its vinyl group attached by π-coordination to Ti(II). The chlorination of 4 by PbCl2 yields ansa-[TiCl2{η5-C5Me4(SiMe2)}2] (8), liberating the btmse ligand. Complex 8 is reduced with a half-equivalent of Mg to give ansa-[TiCl{η5-C5Me4(SiMe2)}2] (9). Compounds 5, 6, and 7 were identified by 1H, 13C, and 29Si NMR spectra. The crystal structures of complexes 3, 4, and 9 have been determined by X-ray crystallography.

Theoretical Studies of the Formation and Reactivity of C2 Hydrocarbon Species on the Fe(100) Surface

The adsorption and reactions of organic fragments containing C2 unit on the iron surface have been investigated employing periodic density functional theory with a plane-wave basis set and pseudopotentials, as well as a slab model representing the p(2 × 2) Fe(100) surface topology. The calculations demonstrate that the most favorable C2 species on the Fe(100) surface are those containing the acetylenic carbon at the α position (i.e., C−CH, C−CH2, and C−CH3). Both the hydrogenation reactions and C−C bond coupling that are responsible for the chain growth process have been explored; it is observed that the most likely mechanism of C−C bond propagation involves the recombination of adsorbed C and CH2/CH3 followed by the migratory insertion of hydrogen at the α C atom. The subsequent β-hydride or reductive elimination results respectively in the evolution of ethylene or ethane. The present computational study indicates that the production of ethane is preferred over ethylene, which agrees with the product sel...

Organic-to-Inorganic Conversion Process of a Cage-Type AlN Precursor Poly(ethyliminoalane)

The organic-to-inorganic conversion process of cage-type poly(ethyliminoalane), (HAlNEt)n (n is mainly 8), was investigated by analyzing the gases evolved during pyrolysis. The conversion process can be divided into three temperature ranges: up to 300°C, 300-600°C, and above 600°C. Below 300°C, ethylene and ethylamine were formed probably via Al-N bond cleavage to form nitrogen terminal (≡N:), and polymerization of cages could occur via two possible reactions involving nitrogen terminals. The conversion process between 300 and 600°C involved the evolution of ethylene, ethane and methane, whose formation can be attributed to radical reactions. Ethylamine was also formed in this temperature range. Methane formation was also observed in the temperature range above 600°C, and appears to be ascribable to the rearrangement of the mineralized network.

Laser-based trace gas detection of ethane as a result of photo-oxidative damage in chilled cucumber leaves (invited)

At low temperatures, high light intensity induces strong photooxidative lipid peroxidation in chilling sensitive cucumber leaves. A sensitive laser-based photoacoustic detector was employed to monitor on-line the evolution of ethane, one of the end products of lipid peroxidation. The Δv=2 CO laser operated in the 2.62–4.06 μm infrared wavelength region with a maximum intracavity power of 11 W. In combination with an intracavity placed photoacoustic cell the laser was able to detect ethane down to 0.5 part per billion. Cucumber leaf disks chilled in the light produce ethane; the rate of ethane production depends on the applied temperature, light intensity, and period of chilling.

Ethylene hydrogenation on Pt thin films on Ni(1 0 0) surface

From XPS and LEED studies, a layer-by-layer growth of Pt thin films is indicated up to 8 ML coverage on Ni(1 0 0) surface while a (1×1) structure changes to a disordered structure above 2 ML of Pt film thickness. The 1 ML Pt overlayer, as a model (1 0 0) surface of Pt–Ni alloy single crystal, shows a considerable d-band narrowing probably due to the formation of an interface state with the Ni substrate. This induces weakly adsorbed hydrogen atoms and ethylene molecules and, as a result, the maximum evolution of ethane is observed around 200 K. A wide d-band extending to −6 eV binding energy is developed for Pt 6 ML film characteristic of bulk Pt electronic states, resulting in a similar surface chemistry of ethylene as on Pt(1 1 1) surface.

Adsorption and reaction of ethylene and hydrogen on Rh(100) surface

Adsorption and reaction of ethylene on clean and H-presaturated Rh(100) have been investigated using HREELS. Adsorption of ethylene on H-presaturated Rh(100) surface at 110 K leads to a π-bonded state, as indicated by a πσ parameter of 0.39 equivalent to that of Zeise's salt. The formation of an ethyl intermediate from the π-bonded ethylene by insertion of preadsorbed H atom already takes place even at 110 K, leading to the evolution of ethane below 200 K. Upon heating, CC bond breakage is promoted on the H-preadsorbed surface, where the strength of metal to H in the adsorbed ethylene is considered to be reduced by preadsorbed hydrogen.

Thermal and photo-induced dissociation of (C2H5)2Zn on Rh(111) surface

The adsorption and dissociation of (C2H5)2Zn were studied on Rh(111) surface. The methods used included X-ray photoelectron spectroscopy (XPS), high resolution electron energy loss spectroscopy (HREELS), Auger electron spectroscopy (AES), temperature-programmed desorption (TPD) and work function measurements (Δφ). Diethyl zinc adsorbs predominantly irreversibly on an Rh surface and causes a work function decrease of 1.3eV. At submonolayer coverage it dissociates even at 90K. Thermal dissociation of adsorbed monolayer occurs at 170–250K very likely through the transient formation of C2H5Zn. The final products of the thermal dissociation, Zn and C2H5 are characterized by Zn(2p3/2) binding energy at 1021.3eV for atomically adsorbed Zn and by vibration losses at 510, 860, 1140, 1430 and 2900cm−1 for adsorbed C2H5. HREELS revealed the formation of adsorbed ethylene in di-σ form, which transforms into ethylidyne at higher temperature. TPD measurements showed the evolution of hydrogen, ethane and butene. The Zn adatoms formed interact strongly with the Rh above 400K, and desorb with Tp=860–915K. Illumination of the molecularly adsorbed layer at 90–95K enhances the extent of the dissociation to ethyl zinc. The possible pathways of the formation of different products are described.

Pyrazole complexes of acyloxydialkylboranes

The reaction of Me3CCOOBEt2 with pyrazole led to the formation of the stable addition complex 1, which was found to be monomeric in solution. The reaction of 9-H-9-borabicyclo[3.3.1]nonane (9-H-9-BBN)2 with pyrazole and pivalic acid yielded a similar complex Me3CCOO(9-BBN)-pzH 2. Crystallographic analysis of 2 revealed a dimeric structure due to the strong hydrogen bonding between azole hydrogen and carbonyl oxygen. The one boron–carbon bond of compound 1 cleaves readily with triethylborane at 20°C with the evolution of ethane, giving a species Me3CCOO(BEt2)2pz 3 with a seven-membered heterocyclic ring as the main structural feature.

Silylation of Styrene with Vinylsilanes Catalyzed by RuCl(SiR3)(CO)(PPh3)2 and RuHCl(CO)(PPh3)3

The coupling reaction of styrene with vinylsilanes catalyzed by ruthenium complexes was investigated. RuHCl(CO)(PPh3)3 (I) and RuCl(SiR3)(CO)(PPh3)2 (where R3 = Me3 (II), Me2Ph (III), (EtO)3 (IV)) were found to be efficient and selective catalysts for the formation of E-1-phenyl-2-silylethene and evolution of ethene. Stoichiometric reactions of styrene with the Ru−Si bonds of II−IV in argon and silylstyrene with the Ru−H bond in air (I*) as well as a MS study of the product of the deuterated styrene with vinylsilanes are convincing evidence for the mechanism of the process involving the migratory insertion of styrene into the Ru−Si bond (and vinylsilane into Ru−H bond) followed by β-H (and β-Si) elimination to give phenylsilylethene (and ethene). Kinetic tests (TOF) indicate a prior dissociation of the PPh3 molecule (or by its oxygenation) from I to yield pentacoordinated RuHCl(CO)(PPh3)2 which is almost as active as II.

β-Hydrogen-Containing Zirconium Alkyls with the Doubly-Bridged Bis(dimethylsilanediyl)dicyclopentadienyl Ligand. X-ray Molecular Structures of [Zr{(SiMe2)2(η5-C5H3)2}ClEt] and [Zr{(SiMe2)2(η5-C5H3)2}Et]2(μ-CH2CH2)

Alkylation of [Zr(CpSi2Cp)Cl2] (CpSi2Cp = (η5-C5H3)2[Si(CH3)2]2 with 1 equiv of RMgCl in THF at 10 °C gave the monoalkylated complexes [Zr(CpSi2Cp)ClR] (R = Et, n-Pr, i-Pr) in 80% yield, the isopropyl complex isomerizing to the n-propyl derivative above 10 °C. Addition of a second equivalent or an excess amount of the akylating agent resulted in the formation of the dialkyl compounds [Zr(CpSi2Cp)R2] (R = Et, n-Pr). Hydrolysis of [Zr(CpSi2Cp)ClR] led to the μ-oxo dinuclear complex [{Zr(CpSi2Cp)Cl}2(μ-O)]. Thermal decomposition of THF solutions of [Zr(CpSi2Cp)ClR] takes place with the evolution of an equimolar amount of alkane and alkene and the formation of [Zr(CpSi2Cp)Cl2] and an unidentified residue. Formation of [Zr(CpSi2Cp)Et2] is always accompanied by decomposition with the evolution of ethane to give [{Zr(CpSi2Cp)Et}2(μ-CH2CH2)] in 70% yield. A similar behavior was observed for [Zr(CpSi2Cp)(n-Pr)2]. All of the compounds were characterized by elemental analysis and NMR spectroscopy, and the molecular ...

The Role in Ozone Phytotoxicity of the Evolution of Ethylene upon Induction of 1-Aminocydopropane-1-carboxylic Acid Synthase by Ozone Fumigation in Tomato Plants

The rate of evolution of ethylene by tomato plants was rapidly increased by O3 fumigation. The time course of the increase in 1-aminocyclop ropane-l-carboxylic acid (ACC) synthase activity was the same as that in the rate of evolution of ethylene, suggesting that ACC synthase activity might be a rate-limiting step in the evolution of ethylene that is caused by O3 fumigation. The rate of the O3-induced evolution of ethylene was increased by the application of ACC to tomato plants, suggesting the involvement of ACC oxidase in the O3-induced evolution of ethylene. Treatment of plants with tiron inhibited the evolution of ethane, but not of ethylene. These results indicated that evolution of ethylene in O 3-treated tomato plants might result from enzymatic reactions catalyzed by both ACC synthase and ACC oxidase, but not from stimulation by O3 of the peroxidation of lipids mediated by free radicals. Pretreatment of leaves with aminoethoxyvinylglycine (AVG), an inhibitor of ACC synthase, significantly inhibited the evolution of ethylene that was induced by O3 and concomitantly reduced the extent of O3-induced visible damage to leaves. Treatment with 2,5-norbonadiene, an inhibitor of the action of ethylene, strongly reduced the extent of visible damage caused by O3, even though it did not suppress the evloution of ethylene. These results indicate that ethylene acts on certain metabolic processes to cause visible damage.

Biological Roles and Biochemistry of the Lipoxygenase Pathway

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