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C7‐Arylated pyrazolo[1,5‐a]azines are important structural motifs with profound applications in drug and material research. Here, we report a general and straighforward synthesis of these bi(hetero)aryls via palladium‐catalyzed direct C−H arylation, employing low‐cost and abundant (hetero)aryl chlorides as the aryl source. The catalytic system is robust and covers a wide substrate scope regarding heteroarenes as well as (hetero)aryl chlorides, with possible extension to the C−H arylation of [1,2,4]triazolo[1,5‐a]pyrimidines. This study also presents a rare example of using (hetero)aryl chlorides for the direct C−H arylation of six‐membered heteroarenes. [ABSTRACT FROM AUTHOR]

An unusual diastereodivergent stereoselective allylation reaction is presented. It consists of a palladium‐catalyzed allylation reaction of an organocatalytically generated amino isobenzofulvene, where the diastereoselectivity is controlled by the electronic properties of a monodentate, achiral ligand on palladium. One major diastereoisomer is formed using triarylphosphines substituted with neutral or electron‐donating substituents of the aryl group, while those with electron‐withdrawing substituents favor the other diastereoisomer. The diastereoselectivity correlates with the Taft inductive parameter of substituents on the triarylphosphine ligand on palladium. The synergistic reaction involves both a catalytic secondary amine catalyst for the indene‐aldehyde activation and the monodentate phosphine ligands on palladium, affording a highly enantioselective reaction with up to 98 % enantiomeric excess. Based on computational investigations, the role of the monodentate phosphine ligand on the diastereoselectivity is discussed. [ABSTRACT FROM AUTHOR]

The Annamite mountains of Vietnam and Laos are a global biodiversity hotspot harboring several threatened endemic species. Conservation efforts to protect these endemics are hampered by a lack of knowledge on their ecology and distribution. We conducted landscape scale camera‐trapping across six study areas in the Annamites to assess distribution patterns of two endemics: the Annamite dark muntjac species complex Muntiacus rooseveltorum/ truongsonensis and the Annamite striped rabbit Nesolagus timminsi. We used a Bayesian single‐species occupancy framework to estimate occupancy as a function of ecological and anthropogenic factors. Our study showed that Annamite dark muntjac was predominantly found at higher elevations (>1000 m) and in areas that were more inaccessible to people and had lower surrounding village density. Annamite striped rabbit exhibited both positive and negative responses to elevation among study areas, with no clear response to the anthropogenic covariates. Our results showed that covariate responses varied among the study areas when random effects were included on study areas. We discuss the application of random effects to investigate species occupancies across large spatial scales, and the risk of not accounting for variation among study areas. Our prediction maps provide the first comprehensive overview of the distribution of these endemic species across a substantial part of their range and can be used to help stakeholders focus conservation efforts on priority areas. [ABSTRACT FROM AUTHOR]

The synthesis of trifluoromethylated cyclopropenes is often associated with important applications in drug discovery and functional materials. In this report, we describe the use of readily available chiral rhodium(II) catalysts for a highly efficient asymmetric cyclopropenation reaction of fluorinated donor–acceptor diazoalkanes with a broad variety of aliphatic and aromatic alkynes. Further studies highlight the unique reactivity of fluorinated donor–acceptor diazoalkanes in the synthesis of oligo‐cyclopropenes. Subsequent C−H functionalization of trifluoromethyl cyclopropenes furnishes densely substituted cyclopropene frameworks and also allows the alternative synthesis of bis‐cyclopropenes. [ABSTRACT FROM AUTHOR]

Tropylium bromide undergoes noncatalyzed, regioselective additions to a large variety of Michael acceptors. In this way, acrylic esters are converted into β‐bromo‐α‐cycloheptatrienylpropionic esters. The reactions are interpreted as nucleophilic attack of bromide ions at the electron‐deficient olefins and the approach of the tropylium ion to the incipient carbanion. Quantum chemical calculations were performed to elucidate the analogy to the amine‐ or phosphine‐catalyzed Rauhut–Currier reactions. Subsequent synthetic transformations of the bromo‐cycloheptatrienylated adducts are reported. [ABSTRACT FROM AUTHOR]

A facile synthetic procedure for the preparation of α‐trifluoromethyl carboxylic acids and esters was achieved through multicomponent coupling reactions between gem‐difluoroalkenes, cesium fluoride, and carbon dioxide. The products were generated in moderate to excellent yields, and the synthetic utility of this method was demonstrated through the preparation of trifluoromethylated versions of popular nonsteroidal anti‐inflammatory drugs (NSAIDs). [ABSTRACT FROM AUTHOR]

Abstract: An Intramolecular Diels‐Alder cycloaddition reaction between a furan diene and an alkynic dienophile was performed within a flow hydrogenator fitted with an inert titanium column at 150 °C, no H2, under 100 bar pressure. A single column pass (tR=1.6 min) afforded ≈55% conversion to the tetrahydroepoxyisoindole carboxamide scaffold with a product turnover of ≈0.035 g/h, a 95% improvement over batch procedures. The cycloaddition protocol is performed in water and ethanol, and does not require catalysts or other additives. Quantitative hydrogenation of the resulting dual π‐bonds within the oxabicyclo system was effected with either a 10% Pd/Al2O3 or 10% Pd/CaCO3 catalyst at 20 °C, 20 bar, with full H2 whereas utilisation of a Raney Ni catalyst under these conditions resulted in a quantitative mono‐olefin reduction of the C4‐C5 double‐bond. With regard to di‐olefin reduction, a degree of stereoselectivity was observed with the aforementioned palladium‐based catalysts yielding exclusive formation of (R) configuration at C7 while utilisation of a 5% Pt/C (sulfided) catalyst at temperatures below 60 °C promoted the formation of the (S)‐isomer at C7. Hence this work further highlights that flow‐hydrogenation provides unprecedented convenience for establishing robust protocols to effect chemoselective transformations. [ABSTRACT FROM AUTHOR]

The development of efficient methods for the metathesis and phosphorylation reactions of disulfide compounds is of widespread interest due to their important synthetic utility in polymer, biological, medicinal and agricultural chemistry. Herein, we demonstrate the use of N-heterocyclic carbenes (NHCs) as versatile organocatalysts to promote these challenging reactions under mild conditions. This metal- and oxidant-free protocol is operationally simple with very short reaction times. The interplay between the nucleophilicity and basicity of NHCs in these reactions were also elucidated by NMR studies and high-level ab initio calculations. [ABSTRACT FROM AUTHOR]

The first three primary members of the non-benzenoid carbocyclic aromatic ion family, namely cyclopropenium, cyclopentadienide, and cycloheptatrienium (tropylium) ions, have planar cyclic structures with (4 n+2)π electrons in fully conjugated systems. They fulfill Hückel's rule for aromaticity and hence possess extraordinary stability. Since the historic discovery of tropylium bromide in the late 19th Century, these non-benzenoid aromatic ions have attracted a lot of attention because of their unique combination of stability and reactivity. The charge on the aromatic ions makes them more prone to nucleophilic/electrophilic reactions than the neutral benzenoid counterparts. Within the last seven years, there has been a large number of investigations in utilizing aromatic ions to mediate organic reactions. This Review highlights these recent developments and discusses the potential of aromatic ions in promoting synthetically useful organic transformations. [ABSTRACT FROM AUTHOR]

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Wildlife conservation is a dynamically complex system, linking seemingly disparate biological and cultural components. This article offers policy professionals an illustration of how a dynamically complex system was diagnosed by applying the system dynamics approach. An integrated method was applied to develop a causal loop diagram, showing the interconnected variables within the system, relating to the conservation status and viability of Cat Ba Langur. Rural poverty, low livelihoods options, human population growth, inappropriate tourism planning and weak management capacity are challenges that have prevented the langur population from increasing over the last decades. Tragedy of commons and shifting the burden systems archetypes were identified and then leverage points for saving the species were proposed. A shift towards the systems perspective of viewing wildlife conservation as the dynamically complex system enables decision-makers to avoid the unintended consequences emerging from the linear thinking, and find sustainable solutions for both wildlife and human. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Interactions with smartphones, which have become more than just communication devices, have wide-reaching consequences on the social harmony of the system in which people, organizations and natural environment co-exist. This study employs a 'systems thinking' approach and uses associated systems tools [causal loop diagrams, systems archetypes and the Bayesian belief network (BBN) modelling] to examine the issue of social dysfunctions resulting from compulsive smartphone use in Singapore. A causal loop diagram was created to map out the interconnected variables within the system, showing many variables relating to the usage of smartphones. Amongst five identified systems archetypes, the 'eroding goals' systems archetype was considered to be the most effective leverage point in the system. The results from a BBN model suggested that small changes made within a family unit to improve on the quality of time spent together could afford benefits to the overall system. The proposed management objective of improving quality of time spent as a family can be utilized by individuals who are determined and willing to reduce social dysfunction in the social environment of which they are a part of. This research encourages business managers and decision-makers to use a systems perspective to look at issues they need to manage, in terms of the issues' relation to other systems components. A shift towards the systems perspective of viewing issues integrates diverse but complementary decision-making and problem-solving methods, in order to find sustainable solutions that afford system-wide benefits. [ABSTRACT FROM AUTHOR]

In recent decades, N-heterocyclic carbenes have become established as a prevalent family of organocatalysts. N-Heterocyclic olefins, the alkylidene derivatives of N-heterocyclic carbenes, have recently also emerged as efficient promoters for CO2 fixation and polymerization reactions. Their extraordinarily strong Lewis/Brønsted basicity suggests great potential as a new class of organocatalysts for a broad range of reactions in synthetic chemistry. [ABSTRACT FROM AUTHOR]

NHC-rhodium complexes (NHC=N-heterocyclic carbenes) have been widely used as efficient catalysts for hydrosilylation reactions. However, the substrates were mostly limited to reactive carbonyl compounds (aldehydes and ketones) or carbon-carbon multiple bonds. Here, we describe the application of newly-developed chelating bis( tzNHC)-rhodium complexes ( tz=1,2,3-triazol-5-ylidene) for several reductive transformations. With these catalysts, the formal reductive methylation of amines using carbon dioxide, the hydrosilylation of amides and carboxylic acids, and the reductive alkylation of amines using carboxylic acids have been achieved under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract: The use of a simple copper salt as a catalyst, in conjunction with CsF as an activator, enabled a wide range of aryl‐ and alkenyltrialkoxysilanes to undergo carboxylation under atmospheric pressure of CO2, affording the corresponding carboxylic acids in good to high yields. [ABSTRACT FROM AUTHOR]

The reductive formylation of amines using CO2 and hydrosilanes is an attractive method for incorporating CO2 into valuable organic compounds. However, previous systems required either high catalyst loadings or high temperatures to achieve high efficiency, and the substrate scope was mostly limited to simple amines. To address these problems, a series of alkyl bridged chelating bis(NHC) rhodium complexes (NHC=N-heterocyclic carbene) have been synthesized and applied to the reductive formylation of amines using CO2 and Ph2SiH2. A rhodium-based bis( tzNHC) complex ( tz=1,2,3-triazol-5-ylidene) was identified to be highly effective at a low catalyst loading and ambient temperature, and a wide substrate scope, including amines with reducible functional groups, were compatible. [ABSTRACT FROM AUTHOR]

Shallow methylene-bridged cavitands appended with simple H-bond donor/acceptor groups are shown to bind aspirin. The structural features needed in a synthetic receptor for aspirin binding are defined. [ABSTRACT FROM AUTHOR]

A copper-catalyzed multicomponent coupling reaction between in situ generated ortho-arynes, terminal alkynes, and carbon dioxide was developed to access isocoumarins in moderate to good yields. The key to this CO2-incorporating reaction was the use of a versatile N-heterocyclic carbene/copper complex that was able to catalyze multiple transformations within the three-component reaction. [ABSTRACT FROM AUTHOR]

We manage the systems we are part of in highly compartmentalized structures. Government departments are typical examples of how society operates in silos. Complex political, environmental, socio-economic and business-financial issues tend to transcend the jurisdictions and capacities of any single government department (silo), which adds significantly to the difficulties in finding systemic management solutions and developing effective governance plans. The government of Haiphong City decided to establish an Evolutionary Learning Laboratory (ELLab) to enhance communication and collaboration between its different departments. This paper discusses the application of the ELLab approach to develop a series of management models for dealing with sustainability issues in Haiphong City and to use these to develop an integrated and cross-sectoral strategic governance plan for the city as a whole. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Newly-developed chelating N-heterocyclic carbene-rhodium complexes catalyze the formal reductive methylation of amines using CO2, the hydrosilylation of amides and carboxylic acids, and the reductive alkylation of amines using carboxylic acids under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Review: [22 refs. [ABSTRACT FROM AUTHOR]

The shown rhodium complex (TZNHC) is the best catalyst for the reductive formylation reaction of amines with CO2 and Ph2SiH2. [ABSTRACT FROM AUTHOR]

Chlorotropylium chloride is successfully applied as a novel coupling reagent for the two-step esterification and amidation reactions of different carboxylic acids. [ABSTRACT FROM AUTHOR]

The use of aliphatic alkynes such as (Vb) is less suitable and even a change in catalyst does not increase the yield significantly. [ABSTRACT FROM AUTHOR]

The reaction proceeds via in situ prepared 1,1-dichlorocycloheptatriene which forms a tropylium cation. [ABSTRACT FROM AUTHOR]

Optimized conditions which include pyrrolidine as the promoter allow the retro aldol hydrolysis of cinnamaldehydes and aliphatic α,β-unsaturated aldehydes. [ABSTRACT FROM AUTHOR]

Introduction: Cannabidiol (CBD) is a non-intoxicating cannabis compound found in diverse commercial products worldwide. However, its use may not be fully harmless. Accordingly, it is important to document the prevalence of CBD use and user characteristics in the general population., Methods: We conducted a nationwide survey from a random sample of adults living in France using computer-assisted telephone interviews between 2 March and 9 July 2022. We estimated the prevalence of CBD awareness and CBD use, and explored the different routes of administration. We also performed logistic regression models to identify factors associated with past-year CBD use., Results: Based on data from 3229 participants, we estimated that 71.0% (95% confidence interval) (69.0-73.0) of the French adult population had heard of CBD, and 10.1% (8.7-11.4) had used it in the previous year. Past-year CBD use was associated with younger age, a higher educational level, not living in a middle-sized urban unit, tobacco consumption and e-cigarette use. The most common route of administration was smoking (56.1%)., Discussion and Conclusion: Past-year CBD use prevalence in France appeared to be as high as that for cannabis. Proper prevention, regulation and control of CBD products is necessary to ensure that people have access to safe and high-quality products. Reliable information on CBD should be sought and disseminated, especially regarding the harms associated with smoking the compound., (© 2024 The Authors. Drug and Alcohol Review published by John Wiley & Sons Australia, Ltd on behalf of Australasian Professional Society on Alcohol and other Drugs.)

Aims: To evaluate the effectiveness of a French mass-media campaign in raising knowledge of both long-term alcohol-related harms (LTH) and low-risk drinking guidelines (LRDG), as well as in lowering alcohol consumption., Design: An 8-month longitudinal survey from February to October 2019, with three waves of on-line data collection (T0 before the campaign, T1 just after it ended and T2 6 months after it ended)., Setting: France., Participants: A total of 2538 adult drinkers (aged 18-75 years)., Measurements: The main outcomes' variables were LTH knowledge (cancer, hypertension, brain haemorrhage), LRDG knowledge (two guidelines: 'maximum of two drinks a day' and 'minimum of 2 days without alcohol per week'), intention to reduce alcohol consumption and self-declared consumption with respect to the French LRDG. At T1, exposure to the campaign was measured using self-reported campaign recall., Findings: In T1, we observed significant positive interactions between exposure group based on campaign recall and survey waves on knowledge of (i) the 'maximum two drinks a day' guideline [adjusted odds ratio (aOR) = 1.32, 95% confidence interval (CI) = 1.08-1.62, P = 0.008], (ii) brain haemorrhage (aOR = 1.80, 95% CI = 1.44-2.25, P < 0.001) and (iii) hypertension (aOR = 1.41, 95% CI = 1.09-1.81, P = 0.008) risks. Campaign exposure was also associated with a significant decrease in at-risk drinking in women (aOR = 0.67, 95% CI = 0.50-0.88, P = 0.004). No significant interaction was observed at T1 for the knowledge of the 'minimum of 2 days without alcohol a week' guideline, or of cancer risk. At T2, no significant interaction was observed for the main outcomes' variables., Conclusions: There appears to be an association between exposure to a 2019 French mass-media campaign to raise knowledge of long-term alcohol-related harms and low-risk drinking guidelines and reduce alcohol consumption and (i) improved knowledge of the 'maximum two drinks per day guideline', (ii) knowledge of the risks of hypertension and brain haemorrhage and (iii) a reduction in the proportion of people exceeding low-risk drinking guidelines (in the general population only). These associations were only observed over the short term and, in some cases, only for certain segments of the population., (© 2022 Society for the Study of Addiction.)

Background and Aims: There is conflicting evidence that use of e-cigarettes promotes cessation in regular smokers, but contrasting findings may be due to differing definitions of vaping. The aim was to assess whether regular use of e-cigarettes while smoking is associated with subsequent smoking cessation., Design: Baseline internet survey with outcomes measured at 6-month follow-up., Setting: All French metropolitan territory., Participants: A total of 2057 smokers aged 15-85 years were recruited through an access panel and responded to a 6-month follow-up: 1805 exclusive tobacco smokers and 252 dual users (tobacco plus regular e-cigarette users) at baseline., Measurements: The three outcomes assessed at 6 months were: a minimum 50% reduction in the number of cigarettes smoked per day, quit attempts of at least 7 days and smoking cessation of at least 7 days at the time of follow-up. Logistic regressions were performed to model the three outcomes according to regular e-cigarette use at baseline, adjusted for socio-economic variables and smoking behaviours., Findings: Baseline dual users were more likely than baseline exclusive tobacco smokers to have halved cigarette consumption [25.9 versus 11.2%, P < 0.001, adjusted odds ratio (aOR) = 2.6, confidence interval (CI) = 1.8-3.8]. Dual users at baseline were also more likely to have made a quit attempt of at least 7 days (22.8 versus 10.9%, P < 0.001, aOR = 1.8, CI = 1.2-2.6). No significant difference was found for 7-day cessation rates at 6 months (12.5 versus 9.5%, P = 0.18, aOR = 1.2, CI = 0.8-1.9)., Conclusions: Among people who smoke, those also using an e-cigarette regularly are more likely to try to quit smoking and reduce their cigarette consumption during the next 6 months. It remains unclear whether regular e-cigarette users are also more likely to stop smoking., (© 2017 Society for the Study of Addiction.)