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Alkyl nitrites (“poppers”) are a diverse class of volatile chemical compounds with a varied legal and medical history. Though once commonly prescribed to treat angina, popper use is now almost exclusively recreational. Currently, poppers are widely available and sold legally under labels like “solvent cleaner”, despite marketing suggesting they are meant to be consumed. As a result, there is little incentive for producers to implement robust quality controls to protect users. In this study, nine common popper brands were analyzed using hydrogen-1 and carbon-13 nuclear magnetic resonance spectroscopy to assess the presence of impurities. Physical labels on all nine samples indicated the contents were “pure” isobutyl nitrite, despite contradictory online marketing in several cases. Spectral results showed isobutyl nitrite was present in all popper samples. However, there was evidence that various unlabeled compounds were also present in all samples. The identity and concentration of these contaminants were not clear, but the seemingly ubiquitous presence of impurities and lack of consistency in the tested samples are concerning and may represent a threat to users’ health. We hope the results of this study draw attention to the potential dangers of recreational popper use and the need to reassess how these compounds are regulated.

Alkyl nitrites ("poppers") are a diverse class of volatile chemical compounds with a varied legal and medical history. Though once commonly prescribed to treat angina, popper use is now almost exclusively recreational. Currently, poppers are widely available and sold legally under labels like "solvent cleaner", despite marketing suggesting they are meant to be consumed. As a result, there is little incentive for producers to implement robust quality controls to protect users. In this study, nine common popper brands were analyzed using hydrogen-1 and carbon-13 nuclear magnetic resonance spectroscopy to assess the presence of impurities. Physical labels on all nine samples indicated the contents were "pure" isobutyl nitrite, despite contradictory online marketing in several cases. Spectral results showed isobutyl nitrite was present in all popper samples. However, there was evidence that various unlabeled compounds were also present in all samples. The identity and concentration of these contaminants were not clear, but the seemingly ubiquitous presence of impurities and lack of consistency in the tested samples are concerning and may represent a threat to users' health. We hope the results of this study draw attention to the potential dangers of recreational popper use and the need to reassess how these compounds are regulated. [ABSTRACT FROM AUTHOR]

In recent years, the range of combined narcotic drugs has widened. New chemical modifications have emerged, including so-called designer drugs, whose action on the body and in particular on the state of vision is increasingly difficult to determine. While the problem of drug abuse is growing drastically, timely detection of a possible toxic damage to the eye induced by drugs and reliable diagnosis differentiating such damage from other etiologies becomes a topical practical issue. The paper presents a clinical case of poppers maculopathy (poppers being a slang name of aromatic volatile alkyl nitrite compounds). Ophthalmological manifestations and differential diagnostic criteria of the damage are described. The mechanisms of action and possible treatment methods are discussed.

Abstract Acute pulmonary embolism may cause right heart failure due to increased pulmonary vascular resistance and arterial hypoxemia. Effective vasodilator therapy of the pulmonary hypertension is highly needed. Therefore, we investigated the effects of a newly developed effective pulmonary vasodilator, the organic mononitrites of 1,2‐propanediol (PDNO), in a rabbit model of acute pulmonary embolism. In anesthetized and ventilated rabbits, systemic and pulmonary hemodynamics, exhaled nitric oxide (NO), plasma nitrite concentration, and blood gases were monitored. First, dose–response experiments with intravenous and left heart ventricle infusions of PDNO and inorganic nitrite were done in naive animals and in pulmonary hypertension induced by a thromboxane A2 analogue. Second, acute pulmonary embolism was induced and either PDNO or placebo were administered intravenously within 20 minutes and evaluated within 1 hour after pulmonary embolization. PDNO intravenously, in contrast to inorganic nitrite intravenously, increased exhaled NO and counteracted pulmonary hypertension and vasodilated the systemic circulation, dose‐dependently, thereby showing efficient NO donation. Pulmonary embolization induced pulmonary hypertension and gas exchange disturbances. PDNO significantly decreased and normalized pulmonary vascular resistance and the right ventricle rate‐pressure product, without causing tolerance, with no significant side effects on the systemic circulation, nor on blood‐gas values or on methemoglobin formation. In conclusion, PDNO is a NO donor and an efficient vasodilator in the pulmonary circulation. Treatment with this or similar organic nitrites intravenously may be a future option to avoid right heart failure in life‐threatening acute pulmonary embolism.

Introduction and Aims: Poppers (alkyl nitrites) are recreational substances commonly used during sexual activity. The current legal status of poppers is complex and wide-ranging bans are increasingly under discussion. Research has identified disproportionate levels of poppers use in sexual minority men. While research on poppers use among sexual minority men exists, little is known about poppers use patterns and correlations with psychosocial and other factors among gay and bisexual young men.Design and Methods: A cross-sectional survey was conducted with 836 Australian gay and bisexual young men aged 18 to 35 years. Descriptive statistics and hierarchical segmentation analyses were conducted to identify poppers use patterns, and correlates of recent poppers use (past 3 months) with personal characteristics, use of other substances, as well as mental and psychosocial health including minority stress, LGBT-community connectedness and participation.Results: High levels of lifetime (38%, n = 315) and recent (24%, n = 204) poppers use were reported. However, few participants reported dependency symptoms, risky consumption or problems arising from using poppers. The final model included three variables (visiting sex-on-premises venues, licensed LGBT venues, and using other substances) and predicted 85% (n = 174) of recent poppers use. No correlations with other concepts or characteristics could be identified.Conclusion: This analysis further supports the hypothesis that poppers may be substances with a comparably low-risk profile. A regulation of poppers with a harm reduction approach may present a valuable public health intervention. [ABSTRACT FROM AUTHOR]

Acute pulmonary embolism may cause right heart failure due to increased pulmonary vascular resistance and arterial hypoxemia. Effective vasodilator therapy of the pulmonary hypertension is highly needed. Therefore, we investigated the effects of a newly developed effective pulmonary vasodilator, the organic mononitrites of 1,2‐propanediol (PDNO), in a rabbit model of acute pulmonary embolism. In anesthetized and ventilated rabbits, systemic and pulmonary hemodynamics, exhaled nitric oxide (NO), plasma nitrite concentration, and blood gases were monitored. First, dose–response experiments with intravenous and left heart ventricle infusions of PDNO and inorganic nitrite were done in naive animals and in pulmonary hypertension induced by a thromboxane A2 analogue. Second, acute pulmonary embolism was induced and either PDNO or placebo were administered intravenously within 20 minutes and evaluated within 1 hour after pulmonary embolization. PDNO intravenously, in contrast to inorganic nitrite intravenously, increased exhaled NO and counteracted pulmonary hypertension and vasodilated the systemic circulation, dose‐dependently, thereby showing efficient NO donation. Pulmonary embolization induced pulmonary hypertension and gas exchange disturbances. PDNO significantly decreased and normalized pulmonary vascular resistance and the right ventricle rate‐pressure product, without causing tolerance, with no significant side effects on the systemic circulation, nor on blood‐gas values or on methemoglobin formation. In conclusion, PDNO is a NO donor and an efficient vasodilator in the pulmonary circulation. Treatment with this or similar organic nitrites intravenously may be a future option to avoid right heart failure in life‐threatening acute pulmonary embolism. [ABSTRACT FROM AUTHOR]

We report a case of cutaneous sensitization to isobutyl nitrite-containing poppers with subsequent elicitation of dermatitis through airborne exposure by proxy. Keywords: airborne dermatitis; alkyl nitrites; allergic contact dermatitis; amyl nitrite; case report; drugs; irritant contact dermatitis; isobutyl nitrite; isopropyl nitrite; poppers EN airborne dermatitis alkyl nitrites allergic contact dermatitis amyl nitrite case report drugs irritant contact dermatitis isobutyl nitrite isopropyl nitrite poppers 212 214 3 02/25/21 20210301 NES 210301 "Poppers" (alkyl nitrites) are drugs used for recreational (sexual) purposes. Airborne dermatitis, alkyl nitrites, allergic contact dermatitis, amyl nitrite, case report, drugs, irritant contact dermatitis, isobutyl nitrite, poppers, isopropyl nitrite. [Extracted from the article]

2-Aminocarboxylic acids have been synthesized through the reaction of lithium acylate α-carbanions with alkyl nitrites to form α-hydroxyiminoacylates, followed by reduction of the latter with tin chloride. The reactions of lithium acylate α-carbanions, generated by the metalation of carboxylic acids with lithium diisopropylamide at 35-40°С in THF under argon, with alkyl nitrites at 45-50°С give 2-hydroxyiminocarboxylic acids in 55-97% yields. The reduction of 2-hydroxyiminocarboxylic acids with tin(II) chloride in conc. HCl at 20-25°С leads to 2-aminocarboxylic acid hydrochlorides in 52-94% yields. [ABSTRACT FROM AUTHOR]

A cyanide-free method for the preparation of 1-(2-pyridyl) isoquinoline-3-carbonitriles (3-cyanoisoquinolines) was developed. The interaction of 5-phenacyl-3-(2-pyridyl)-1,2,4-triazines with 1,2-dehydrobenzene generated in situ from anthranilic acid and an excess of amyl nitrites afforded the target compounds in good yields. The proposed mechanism involves the in situ transformation of the 5-phenacyl group into the 5-cyano group under the action of alkyl nitrite and the following inverse demand aza-Diels--Alder reaction of thus formed 5-cyano-1,2,4-triazines with 1,2-dehydrobenzene affording the target products. The presence of the 5-phenacyl substituent is a key for the reaction, as in case of 5-styryl- or 5-phenylethynyl-3-(2-pyridyl)-1,2,4-triazines the formation of the 1,2,4-triazine ring-transformation products was observed [ABSTRACT FROM AUTHOR]

Background: "Poppers" is a slang term for a group of alkyl nitrites that are used as recreational drugs. Their inhalative intoxication leads to muscle relaxation, analgesia, and euphoria. Maculopathy is a rare but serious side-effect. Patients/methods: Clinical, imaging, and electrophysiological findings of seven patients with maculopathy after consumption of poppers were presented. Results: All seven patients were male with a median age of 35 years (range 28-45 years), the median duration of periodical poppers use until the onset of symptoms was 9.8 years (one day to 25 years). Five of seven patients were HIV-positive, one patient was negative, and the HIV-status of one patient was unknown. Median average of visual acuity at presentation was 20/30 in each eye. In all patients, optical coherence tomography (OCT) showed pathognomonic alterations of the outer foveal retina. One patient showed an almost complete restitution of the maculopathy six months after cessation of drug use and following the oral intake of Lutein. Imaging alterations returned to normal and visual acuity recovered from 20/50 and 20/30 (right and left eye, respectively) to 20/20 on both eyes. Follow up of two other cases showed no relevant functional decline or improvement. Discussion: Toxic maculopathy due to the consumption of poppers is an important differential diagnosis in acute visual loss without clinico-morphological correlate. Optical coherence tomography is the only reliable diagnostic tool in these cases. Complete recovery of visual function and macular morphology is rare, even after cessation of drug abuse. Oral lutein therapy may have a beneficial effect. [ABSTRACT FROM AUTHOR]

The abuse of alkyl nitrites is common among adolescents and young adults worldwide. However, the information regarding the effects of alkyl nitrites on the central nervous system and the associated psychological abuse potential is scarce. The abuse potential of 3 representative alkyl nitrites – isobutyl nitrite, isoamyl nitrite, and butyl nitrite – was evaluated in mice using conditioned place preference tests with an unbiased method. The dopamine levels released by synaptosomes extracted from the striatal region were measured using high performance liquid chromatography. Mice treated with the test substances (50 mg/kg, i.p.) exhibited a significantly increased drug-paired place preference. Moreover, greater levels of dopamine were released by striatal region synaptosomes in response to isobutyl nitrite treatment in mice. Thus, our findings suggest that alkyl nitrites could lead to psychological dependence and dopaminergic effects. Furthermore, these results provide scientific evidence to support the regulation of alkyl nitrites as psychoactive substances in the future. [ABSTRACT FROM AUTHOR]

A novel continuous-flow approach for the synthesis of fluoroalkyl-substituted diazomethanes has been developed. Utilizing a cheap, self-made microreactor fluoroalkyl-substituted amines were transformed into the corresponding diazomethanes using tert-butyl nitrite and acetic acid as catalyst. These diazomethanes were employed in [2+3] cycloaddition reactions with olefins and alkynes, yielding valuable pyrazolines and pyrazoles in good to excellent yields. [ABSTRACT FROM AUTHOR]

This study aims to determine the relationship between recreational drug use in HIV-positive males in the past year and socio-economic factors and/or social support networks in Japan. A national online survey in a cross-sectional study was conducted by HIV Futures Japan project from July 2013 to February 2014. Of the 1095 HIV-positive individuals who responded, 913 responses were determined to be valid; responses from the 875 males were analysed. A total of 282 participants used addictive drugs (32.2%) in past year. New psychoactive substances were used by 121 participants (13.8%), methamphetamine or amphetamine by 47 (5.4%), air dusters/sprays/gas by 31 (3.5%), 5-methoxy-N,N-diisopropyltryptamine (5MeO-DIPT) by 16 (1.8%) and cannabis (1.0%) by 9. Multiple logistic regression analysis was performed with the use of alkyl nitrites, addictive drugs, air dusters and thinners, which are low illegality, as dependent variables. We found that the odds ratio (95% confidence interval) for use among participants with full-time and temp/contracted/part-time employees compared to management/administration professions were 2.59 (0.99–6.77) and 2.61 (0.91–7.51). Also, a correlation was observed between alkyl nitrites and new psychoactive substances and usage rates in people engaged in few HIV-positive networks. It is necessary to develop targeted policies for drug use prevention and user support among HIV-positive men and to support and provide care for drug users who are isolated or have a narrow HIV/AIDS support network. [ABSTRACT FROM AUTHOR]

The enthalpy and activation energy of reactions involving attack by MeO and MeO on CH groups of 2-butyl nitrite and 2-nitrosobutane have been calculated by quantum chemical methods. The abstraction of a hydrogen atom is accompanied, in the former case, by concerted N-O bond breaking and, in the latter case, by concerted C-N bond breaking, resulting in NO• formation. On the basis of the results obtained, an algorithm has been developed within the intersecting parabolas model for calculating the enthalpies, activation energies, and rate constants of these types of reactions involving alkyl, alkoxyl, aminyl, peroxyl, phenoxyl, thiyl, and hydroxyl radicals. [ABSTRACT FROM AUTHOR]

Although alkyl nitrites are used as recreational drugs, there is only little research data regarding their effects on the central nervous system including their neurotoxicity. This study investigated the neurotoxicity of three representative alkyl nitrites (isobutyl nitrite, isoamyl nitrite, and butyl nitrite), and whether it affected learning/memory function and motor coordination in rodents. Morris water maze test was performed in mice after administrating the mice with varying doses of the substances in two different injection schedules of memory acquisition and memory retention. A rota-rod test was then performed in rats. All tested alkyl nitrites lowered the rodents’ capacity for learning and memory, as assessed by both the acquisition and retention tests. The results of the rota-rod test showed that isobutyl nitrite in particular impaired motor coordination in chronically treated rats. The mice chronically injected with isoamyl nitrite also showed impaired function, while butyl nitrite had no significant effect. The results of the water maze test suggest that alkyl nitrites may impair learning and memory. Additionally, isoamyl nitrite affected the rodents’ motor coordination ability. Collectively, our findings suggest that alkyl nitrites may induce neurotoxicity, especially on the aspect of learning and memory function. [ABSTRACT FROM AUTHOR]

Alkyne C≡C bond breaking, outside of alkyne metathesis, remains an underdeveloped area in reaction discovery. Recently, nitrogenation has been reported to allow nitrile formation from alkynes. A new protocol for the metal-free C≡C bond cleavage of terminal alkynes to produce nitriles is reported. This method provides an opportunity to synthesize a vast range of nitriles containing aryl, heteroaryl, and natural product derivatives (38 examples). In addition, the potential of tBuONO to act as a powerful nitrogenating agent for terminal aryl alkynes is demonstrated. [ABSTRACT FROM AUTHOR]

We present a DC slice imaging study of the decomposition of C2, C3 and C4 nitroalkanes and alkyl nitrites, focusing on the NO elimination channel, possibly a minor pathway. Infrared multiphoton dissociation (IRMPD) is used to induce dissociation on the ground electronic state under collisionless conditions. The channels that produced NO as a product were studied and compared among the target molecules to gain a better understanding of the isomerization of the nitroalkanes prior to dissociation. Trends in the total translational energy and NO rotational temperatures obtained from the images are discussed. [ABSTRACT FROM AUTHOR]

Background: The term 'inhalants' is commonly used to describe a group of drugs that are characterised by the route of administration. There are three main sub-groups of inhalants; volatile solvents, alkyl nitrites, and nitrous oxide. These drugs all have different pharmacological properties, use patterns, and potential harms; yet they are sometimes grouped together in survey instruments. This critical review aimed to present a comparative analysis of how these inhalant drugs are defined, and use measured, across a range of population-level drug use surveys., Methods: Population-level drug use surveys of youth (n=5) and general population (n=6), which measured use of at least once type of inhalant drug, were analysed as case studies. The types of inhalants surveyed were extracted, as well as definitions of these drugs, from code books or survey methods., Results: Differing definitions were used between surveys, and included differences between countries, and between surveys intended to measure youth and general population drug use. Of the six general population surveys; five reported nitrous oxide use, five reported volatile solvent use, and four reported alkyl nitrite use. Of the five youth-specific surveys; three reported volatile solvent use, whereas only one reported on alkyl nitrite use, and one reported nitrous oxide use., Conclusions: There is no consistent approach used to define or measure the use of inhalant drugs, which has implications for global comparisons and understanding drug use in different populations. We conclude that the term 'inhalants' should be discontinued, due to the limited value in continuing to group very different types of drugs solely on the basis of their route of administration. Improving the epidemiology of volatile solvents, alkyl nitrites, and nitrous oxide as distinct drug types will be of benefit to harm reduction, treatment, and prevention efforts, and ensure these are targeted appropriately to population groups and context of use., Competing Interests: Declarations of Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

A three-component carboetherification of unactivated alkenes has been developed allowing the rapid building of complexity from simple starting materials. A wide range of α-substituted styrenes underwent smooth reactions with unactivated alkyl nitriles and alcohols to afford γ-alkoxy alkyl nitriles with concomitant generation of a quaternary carbon center. A radical clock experiment provided clear-cut evidence that the reaction proceeds through a tertiary alkyl radical intermediate. [ABSTRACT FROM AUTHOR]

While men who have sex with men (MSM) in North America have commonly used alkyl nitrite “poppers,” related to the vasodilator amyl nitrite, in sexual contexts since at least the 1970s, they do not have a significant history of using solvent or propellant inhalants, known as “huffing.” This may be changing, with some solvents being marketed as a “new form of poppers.” Huffing solvents carries considerably more health risk than using alkyl nitrite poppers, but this may not be recognized by clinicians, who usually have little knowledge of either, or MSM, who do not have a cultural history of huffing. We discuss this potential recent trend and health risks. [ABSTRACT FROM PUBLISHER]

In this contribution we use computational tools to investigate the reaction of alcohol substrates with reactive nitrogen oxide species such as NO and NO, leading to the formation of alkyl nitrites. These nitrites are interesting intermediates which can be processed to various valuable chemicals such as ketones/aldehydes and dimethyl oxalate while regenerating NO. As such, NO is used as an oxidation mediator, converting alcohol substrates to more reactive nitrites which can be selectively converted to more desired compounds, closing a catalytic cycle in NO species. [ABSTRACT FROM AUTHOR]

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Visible advance: A mild, one‐pot Stadler–Ziegler process for CS bond formation has been developed. The method employs the photoredox catalyst [Ru(bpy)3Cl2]⋅6 H2O irradiated with visible light. A variety of aryl–alkyl and diaryl sulfides were prepared from readily available arylamines and aryl/alkylthiols in good yields. The use of a photo microreactor led to a significant improvement with respect to safety and efficiency. [ABSTRACT FROM AUTHOR]

Alkyl nitrites have been used previously to produce alkoxyradicals,which are important intermediates in the oxidation of alkanes in atmosphericand combustion processes. Substituted alkoxy radicals, particularyhydroxyalkoxy radicals, are also important intermediates in the atmosphericoxidation of alkenes and combustion of alcohols. In order to producesubstituted alkoxy radicals we have photolyzed at 351 nm substitutedalkyl nitrites, XCH2CH2ONO (X = F, Cl, Br, OH).Using laser-induced fluorescence only in the case of X = F do we observethe spectrum of substituted alkoxy radical, XCH2CH2O; but we always observe the electronic transitions of formaldehyde,HCHO, and vinoxy radical, CH2CHO. HCHO can be formed bythe dissociation of XCH2CH2O in its ground stateas the barrier to C–C bond dissociation is less than the photonenergy remaining after O–NO bond breakage. However, the barrieralong the reaction path directly leading from XCH2CH2O to CH2CHO + HX is much higher than the availableenergy remaining after O–NO bond breakage. A roaming mechanism,involving a frustrated dissociation of X followed by HX extraction,might explain the apparent paradox. Under the conditions of our observationsvinoxy retains considerable vibrational excitation but the observedrotational temperatures of both HCHO and CH2CHO are ?7K. [ABSTRACT FROM AUTHOR]

BackgroundPoppers are a recreational substance of abuse belonging to the alkyl nitrite family of compounds. In the United Kingdom, where they are legal to purchase but illegal to sell for human consumption, 10% of the general population have tried them. They are considered low risk to physical and mental health. Two recent case series from France demonstrated foveal pathology in individuals associated with poppers use.MethodA case series of seven patients presenting to four hospitals in the United Kingdom with visual impairment and maculopathy associated with inhalation of poppers.ResultsAll patients experienced visual symptoms associated with poppers use. The majority had impaired visual acuity, central scotomata, distortion, or phosphenes. Clinical signs on fundoscopy ranged from normal foveal appearance to yellow, dome-shaped lesions at the foveola. Spectral domain optical coherence tomography (SD-OCT) showed varying degrees of disruption of the presumed inner segment/outer segment (IS/OS) junction.DiscussionAlthough poppers have been in use for several decades, in 2007, following legislative changes, there was a change in the most commonly used compound from isobutyl nitrite to isopropyl nitrite. There were no reports of 'poppers maculopathy' before this. Poppers maculopathy may be missed if patients are not directly questioned about their use. The disruption or loss of the presumed IS/OS junction on SD-OCT are a characteristic feature. Further study of maculopathy in poppers users is now needed. Raising public awareness of the ocular risks associated with their use may be necessary. [ABSTRACT FROM AUTHOR]

The primary products of n-butoxy and2-pentoxyisomerization in the presence and absence of O2have beendetected using pulsed laser photolysis-cavity ringdown spectroscopy(PLP-CRDS). Alkoxy radicals n-butoxy and 2-pentoxywere generated by photolysis of alkyl nitrite precursors (n-butyl nitrite or 2-pentyl nitrite, respectively), andthe isomerization products with and without O2were detectedby infrared cavity ringdown spectroscopy 20 μs after the photolysis.We report the mid-IR OH stretch (ν1) absorption spectrafor δ-HO-1-C4H8•, δ-HO-1-C4H8OO•, δ-HO-1-C5H10•, and δ-HO-1-C5H10OO•.The observed ν1bands are similar in position andshape to the related alcohols (n-butanol and 2-pentanol),although the HOROO• absorption is slightly stronger than theHOR• absorption. We determined the rate of isomerization relativeto reaction with O2for the n-butoxy and2-pentoxy radicals by measuring the relative ν1absorbanceof HOROO• as a function of [O2]. At 295 K and 670Torr of N2or N2/O2, we found rateconstant ratios of kisom/kO2= 1.7 (±0.1) × 1019cm–3for n-butoxy and kisom/kO2= 3.4(±0.4) × 1019cm–3for2-pentoxy (2σ uncertainty). Using currently known rate constants kO2, we estimate isomerization ratesof kisom= 2.4 (±1.2) × 105s–1and kisom≈ 3 × 105s–1for n-butoxy and 2-pentoxy radicals, respectively, where theuncertainties are primarily due to uncertainties in kO2. Because isomerization is predicted to bein the high pressure limit at 670 Torr, these relative rates are expectedto be the same at atmospheric pressure. Our results include correctionsfor prompt isomerization of hot nascent alkoxy radicals as well asreaction with background NO and unimolecular alkoxy decomposition.We estimate prompt isomerization yields under our conditions of 4± 2% and 5 ± 2% for n-butoxy and 2-pentoxyformed from photolysis of the alkyl nitrites at 351 nm. Our measuredrelative rate values are in good agreement with and more precise thanprevious end-product analysis studies conducted on the n-butoxy and 2-pentoxy systems. We show that reactions typically neglectedin the analysis of alkoxy relative kinetics (decomposition, recombinationwith NO, and prompt isomerization) may need to be included to obtainaccurate values of kisom/kO2. [ABSTRACT FROM AUTHOR]

A highly efficient metal-free catalytic system, 1,3-dibromo-5,5-dimethylhydantoin (DBDMH)–tert-butylnitrite (TBN)–H2O, has been developed for an environmentally friendly and economical aerobic acid-free oxidation of sulfides. TBN was identified as an efficient NO equivalent for the activation of molecular oxygen. Under optimal conditions, a variety of sulfides substrates were converted into their corresponding sulfoxides in good yields by molecular oxygen. [ABSTRACT FROM AUTHOR]

A straightforward and efficient method for the synthesis of nitriles or β-cyanocarbonyls via Knoevenagel condensation and Michael addition reaction of a barbituric acid, aldehyde and sodium cyanide in water without using any catalyst or activation at 70 °C is reported. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) based calculations are performed on a series of alkyl nitrites and nitroalkanes representing large-scale primary, secondary, and tertiary nitro compounds and their radicals resulting from the loss of their skeletal hydrogen atoms. Geometries, vibration frequencies, and thermochemical properties [S°(T) and C°p(T) (10 K ⩽ T ⩽ 5000 K)] are calculated at the B3LYP/6-31G(d,p) DFT level. ΔfH°298 values are from B3LYP/6-31G(d,p), B3LYP/6-31+G(2d,2p), and the composite CBS-QB3 levels. Potential energy barriers for the internal rotations have been computed at the B3LYP/6-31G(d,p) level of theory, and the lower barrier contributions are incorporated into entropy and heat capacity data. The standard enthalpies of formation at 298 K are evaluated using isodesmic reaction schemes with several work reactions for each species. Recommended values derived from the most stable conformers of respective nitro- and nitrite isomers include -30.57 and -28.44 kcal mol-1 for n-propane-, -33.89 and -32.32 kcal mol-1 for iso-propane-, -42.78 and -41.36 kcal mol-1 for tert-butane-nitro compounds and nitrites, respectively. Entropy and heat capacity values are also reported for the lower homologues: nitromethane, nitroethane, and corresponding nitrites. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 181–199, 2010 [ABSTRACT FROM AUTHOR]

Abstract: The mechanistic aspects of the photo induced reactions of gaseous amyl nitrite have been investigated using ab initio calculations. We show that the C5H11O–NO bond dissociation mechanism is different on the S1 and S2 surfaces, respectively. The subsequent conformational changes in the ground state 1-pentoxy radical involves several barriers. Interestingly, we show that the intramolecular 1,5-H transfer in the 1-pentoxy radical proceeds in the opposite direction on the S1 state compared to the S0 reaction. Moreover, the results show that the excited state reaction of the alkoxy radical may be a proton transfer that proceeds on a repulsive surface. [Copyright &y& Elsevier]

Abstract: A method for the safe and reliable iododeamination of aromatic and heteroaromatic amines under copper-free conditions is described and its scope is evaluated. [Copyright &y& Elsevier]

The first transition-metal-free addition of alkyl nitriles to unactivated imines was developed using a catalytic combina- tion of 4-MeOC6H4ONa and TMSCH2CO2Et to promote the reaction. The corresponding β-amino nitriles are obtained in good to almost quantitative isolated yields under mild conditions. A mechanism involving an autocatalytic pathway is proposed on the basis of experimental observations. [ABSTRACT FROM AUTHOR]

Photodissociation of methyl nitrite and n-butyl nitrite at 266 and 355 nm has been investigated in the gas phase at room temperature. OH photoproducts were observed, and their internal state distributions were measured by the one-photon laser-induced fluorescence (LIF) technique. It was found that the nascent OH from the 266 nm photolysis of methyl nitrite was vibrationally cold, and its rotational state distribution conformed to a Boltzmann behavior with a rotational temperature of Trot= 2200 ± 150 K. In contrast, the nascent OH from the 266 nm photolysis of n-butyl nitrite was found to be vibrationally excited, and the measured relative population of v′′ = 0:1 was 0.78:0.22. The rotational state distribution of the OH v′′ = 1 state conformed to Boltzmann behavior, with a rotational temperature of Trot= 1462 ± 120 K. However, a simple Boltzmann distribution was not found for the OH v′′ = 0 state. In the photolysis of n-butyl nitrite at 355 nm, the OH fragment was found to be vibrationally cold and its rotational state distribution showed non-Boltzmann behavior. A photodissociation mechanism involving an intramolecular hydrogen atom transfer process is proposed for the OH product pathway for methyl nitrite, which has been compared with the potential energy surfaces obtained from density functional theory (DFT) calculations. A photodissociation mechanism of n-butyl nitrite is also proposed for the OH product pathway, which differs from that of methyl nitrite due to the effects of the different alkoxy substituents. [ABSTRACT FROM AUTHOR]

Background: Poppers (alkyl nitrites) are vasodilators used by many gay, bisexual, and other men who have sex with men (GBMSM) to relieve pain, enhance pleasure, and facilitate penetration during sex. In 2013, the Canadian government cracked down on the sale of poppers products, however prevalence of poppers use among GBMSM in Canada remains high. Poppers have been studied by medical researchers since the 1980s, yet qualitative and community-based research to inform federal policy, remains somewhat less common.Methods: We conducted a critical interpretive synthesis (CIS) to better understand poppers health literature using the medical model of health as a point of reference. Analysis was performed using inductive and deductive methods including reflexive note-taking, mind-mapping, and close coding. 153 publications were identified to inform this review of which 5 were chosen for coding based on a purposive sampling framework.Results: Our findings are unified within a theoretical construct we term responsibility. Responsibility is a construct we use to describe the bias we identified in health sciences literature regarding poppers use that tends to exaggerate the necessity for poppers cessation, and devalue both the benefits of poppers use and the perspectives and experiences of people who use poppers. The emphasis on individual behavior change within the literature appears to be motivated less by objective measures or assessments of health risks and outcomes, and more by harmful stereotypes that position gay men and people who use drugs as inherently irresponsible.Conclusion: We conclude by discussing how these findings have important implications for the review of current policy on poppers sales in Canada which remains influenced by a literature base prejudiced by factors such as homophobia, heteronormativity, and drug stigma, and recommend areas for future work. [ABSTRACT FROM AUTHOR]

In this paper we describe the unprecedented reaction between α-diazo esters 1 and iodine. The reaction, carried out in the presence of aqueous NaHCO3, afforded the Z-isomer of the corresponding unsaturated-2-iodo ester 8. The configuration of compounds 8 was determined using the 3JC&bond;H coupling between carbonyl carbon atom and alkene proton. Mechanistic considerations accounting for the observed phenomena and including quantum chemical calculations are proposed. Copyright © 2008 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An accelerated quantum chemical molecular dynamical code “Colors-Excite” was used to investigate the photolysis of alkyl nitrites series, RONO (RᆖCH3 and C(CH3)3) on copper surfaces. Our calculations showed that the photo-dissociated processes are associated with the alkyl substituents of RONO when adsorbed on copper surfaces. For RᆖCH3, a two-step photolysis reaction occurred, yielding diverse intermediate products including RO radical, NO, and HNO, consistent with those reported in gas phase. While for RᆖC(CH3)3, only one-step photolysis reaction occurred and gave intermediate products of RO radical and NO. Consequently, pure RO species were achieved to adsorb on metal surfaces by removing the NO species in photolysis reaction. The detailed photo-dissociated behaviors of RONO on copper surfaces with different alkyl substituents which are uncovered by the present simulation can be extended to explain the diverse dissociative mechanism experimentally observed. The quantum chemical molecular dynamical code “Colors-Excite” is proved to be highly applicable to the photo-dissociations on metal surfaces. [Copyright &y& Elsevier]

Abstract: The photodissociation of alkyl nitrites series (RONO) in gaseous state were studied using density functional theory with Amsterdam Density Functional program (ADF2000) and quantum chemical molecular dynamical method by “Colors-Excite” code. The different dissociative phenomena have been explained by this investigation. Alkyl nitrites were shifted to their excited states by capturing the light energy and the bonds of O–N (RO–NO) were broken. A two-step reaction occurred for methyl nitrite (THN) to yield the diverse products, such as RO radical, NO and HNO, whereas only one-step reaction occurred for tert-butyl nitrite (TBN). The consistent results in theoretical calculation and experiment, including geometrical structures and excitation energies, demonstrated the good performances of “Colors-Excite”. [Copyright &y& Elsevier]

Abstract: A method for the synthesis of peroxynitrite is described. It involves nitrosation of H2O2 at pH⩾12.5 by isoamyl or butyl nitrite in mixed solvents of isopropyl alcohol (IPA) and water at 25±1°C. Maximum yields of peroxynitrite are obtained after 15 min of incubation at IPA concentrations of 30–70% (v/v). The solutions of peroxynitrite are processed for removal of IPA and isoamyl alcohol by solvent extraction. Unreacted H2O2 is removed by catalytic decomposition on granular MnO2. The post processed solutions of peroxynitrite are useful in several chemical and biochemical investigations where bolus additions are required. The method as reported is amenable for large scale synthesis as it involves sequential mixing of solvents (water and IPA) to alkali followed by the addition of H2O2 and alkyl nitrite. [Copyright &y& Elsevier]

Alcohols in acetonitrile are converted into alkyl nitrates, nitrites, or thiocyanates by the action of triphenylphosphine and trichloroisocyanuric acid along with silver nitrate, silver nitrite, or sodium thiocyanate, respectively. [ABSTRACT FROM AUTHOR]

Volatile alkyl nitrites have been used during the past decades for “recreational purposes,” and for intensifying sexual experience. Their use has been associated with methemoglobinemia and hemolysis. We report three patients who presented over the past year with acute hemolysis after inhalation of butyl nitrite, two of them had glucose-6-phosphate dehydrogenase (G6PD) deficiency. [ABSTRACT FROM AUTHOR]

We review some of the work that we have been doing in the field of chemical kinetics on the reactivity of alkyl nitrites in microorganized media. For comparative purposes, the reactivity of alkyl nitrites in water, organic solvents, aqueous β-cyclodextrin solutions and aqueous micellar solutions is reviewed. After a brief description of common properties of alkyl nitrites and of microorganized media, we report kinetic studies on the reactivity of alkyl nitrites. The emphasis is on three important reactions undergone by these reagents in solution, namely acid-catalysed hydrolysis, base-catalysed hydrolysis and NO-transfer reactions, mainly to amines to produce nitroso compounds. The principal features observed through the experimental study of these reactions allow reaction mechanisms in each reaction medium to be prepared; these give information on the constitution of the transition state and its energy characteristics, the presence of possible intermediates, the effects of structural variation on rate and the role of the solvent. [ABSTRACT FROM AUTHOR]

The “donor-induced” generation of nitrosonium cation in acidified solutions of alkyl nitrites in dichloromethane is demonstrated spectroscopically. Electron-rich organic molecules, including polymethylbenzenes and thioethers, affect the donor-induced release of nitrosonium as the corresponding electron donor–acceptor complex [donor, NO+]. These complexes are spectrally identified using a combination of UV–vis and IR spectroscopy. The almost quantitative formation of the [donor, NO+] EDA complex with hexamethylbenzene and butyl sulfide as donors is verified with UV–vis spectroscopy. [ABSTRACT FROM AUTHOR]