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Evaluating the ability of perennial ryegrass to continue underpinning New Zealand’s low-cost dairy production systems under future climate change scenarios requires a modelling approach. In this study, climate projections for different climate change scenarios were used in the BASGRA pasture model to predict changes in annual yields and seasonal pasture growth rate patterns of perennial ryegrass. These predictions, including uncertainty, were made for the years 2010-2014, 2040- 2044 and 2090-2094 in 14 dairy-dominant subregions in the Upper North Island of New Zealand. The suitability of perennial ryegrass is expected to decline in the future across all subregions, with worse outcomes expected under higher atmospheric greenhouse gas levels. Winter is expected to be the season least affected by climate change and summer the most affected. Late-winter/spring is predicted to become the main growing season, followed by late-autumn/early-winter. The ability offarmers to adapt their farming practices is essential in remaining profitable and internationally competitive.

NR4F salts simultaneously catalyse and template the reaction of dithiols with C6F6 to generate the first fluorinated corona[n]arenes. Simple SNAr functionalisation of the fluoraryl units easily afford diverse libraries of macrocyclic building blocks.

The Alder-ene reaction of neat polyisobutylene (PIB) and maleic anhydride (MAA) to produce the industrially important lubricant additive precursor polyisobutylene succinic anhydride (PIBSA) is studied at 150-180 °C. Under anaerobic conditions with [PIB] ∼1.24 M (550 g mol-1 grade, >80% exo alkene) and [MAA] ∼1.75 M, conversion of exo-PIB and MAA follows second-order near-equal rate laws with kobs up to 5 × 10-5 M-1 s-1 for both components. The exo-alkene-derived primary product PIBSA-I is formed at an equivalent rate. The less reactive olefinic protons of exo-PIB also react with MAA to form isomeric PIBSA-II (kobs up to 6 × 10-5 M-1 s-1). Some exo-PIB is converted to endo-PIB (containing trisubstituted alkene) in a first-order process (kobs ∼1 × 10-5 s-1), while PIBSA-I is difunctionalized by MAA to bis-PIBSAs very slowly. The MAA- and PIB-derived activation parameter ΔG‡(150 °C) 34.3 ± 0.3 kcal mol-1 supports a concerted process, with that of PIBSA-I suggesting a late (product-like) transition state.

Cyclization of substituted thiosemicarbazones with α-bromo-4-cyanoacetophenone allows rapid single-step sustainable syntheses of 4-cyanophenyl-2-hydrazinylthiazoles libraries (30 examples, 66-79%). All show anticancer efficacy against HCT-116 and MCF-7 carcinoma cell lines with the majority being more active than cisplatin positive controls. The compounds 2-(2-(2-hydroxy-3-methylbenzylidene)hydrazinyl)-4-(4-cyanophenyl)thiazole (3f) and 2-(2-((pentafluorophenyl)methylene)-hydrazinyl)-4-(4-cyanophenyl)thiazole (3a') show optimal GI

Thiazole has been a key scaffold in antidiabetic drugs. In quest of new and more effective drugs a simple, efficient, high yielding (67-79 %) and convenient synthesis of arylidenehydrazinyl-4-methoxyphenyl)thiazoles is accomplished over two steps. The synthesis involved the condensation of aryl substituted thiosemicarbazones and 2-bromo-4-methoxyacetophenone in absolute ethanol. The structures of the resulting thiazoles are in accord with their UV/VIS, FT-IR

Previously inaccessible large S

Historic and elite universities need to manage their reputation whilst facing up to problematic aspects of their own history. We determine contemporary readings of place and space require narratives to align with current, corporate thinking and values. In recent years, colonialism and slavery have been at the forefront of campaigns which, while they tend to originate as student-led, have resulted in historic universities having to ‘face up’ to their own role. We here focus on the University of Virginia which alongside nearby Monticello, has symbolic and charismatic hagiographic remembering afforded to the founder Thomas Jefferson. We note how competitively selected student guides are evidencing cultural change in the present as well as forming part of the alumni and present student ‘family’, where pride in place is contingent on such openness. Our study makes a contribution to our understanding of historic universities as heritage businesses.

A Bayesian chemistry-assisted hydrograph separation (BACH) approach was previously demonstrated using 15 years of monthly total phosphorus (TP) and total nitrogen (TN) data from eight mesoscale catchments in New Zealand’s North Island. Calibration was done separately for three 5-year data periods, and in each period, concentrations of the two tracers (TP and TN) discharged from each of the three separated flow paths—fast (event-response near-surface flow), medium (seasonal shallow local groundwater flow), and slow (persistent deeper regional groundwater flow)—were assumed to be constant. This approach has now been extended to reveal non-linear trends in the tracer concentrations in each flow path, each represented using a four-parameter curve (initial and final values of a linear trend plus two harmonics). The extended method (called BACH2) identified clear TP and TN concentration trends in the medium and slow flow paths in most of the eight catchments. TP and TN concentration trends in the fast flow path were generally uncertain, however, due to the infrequency and inherent variability of concentrations sampled during high flow conditions. Concentrations closely matched previously published results from the constant-concentration BACH model calibrated to shorter data series. The BACH2 approach is a powerful tool for revealing concentration trends in the different pathways that sustain stream flow using commonly available water quality and flow data. This type of analysis has not previously been available outside of complex distributed simulation models.

The synthesis of cyclacene nanobelts remains an elusive goal dating back over 60 years. These molecules represent the last unsynthesized building block of carbon nanotubes and may be useful both as seed molecules for the preparation of structurally well-defined carbon nanotubes and for understanding the behavior and formation of zigzag nanotubes more broadly. Here we report the discovery that isomers containing two Dewar benzenoid rings are the preferred form for several sizes of cyclacene. The predicted lower polyradical character and higher singlet-triplet stability that these isomers possess compared with their pure benzenoid counterparts suggest that they may be more stable synthetic targets than the structures that have previously been identified. Our findings should facilitate the exploration of new routes to cyclacene synthesis through Dewar benzene chemistry.

Polypharmacy in older adults is a growing problem, as some drugs may be either unnecessary or even harmful. Admission to hospital under a Medicine for the Elderly specialist physicians represents an opportunity to review patients’ medication. The recent introduction of electronic prescribing to some hospitals in the United Kingdom allows the development of tools to measure polypharmacy in in-patients, and subsequently to assess the efficacy of interventions that aim to optimize medication prescribing. We tested the feasibility of developing an Excel-based software code that measured the number of medications a group of patients were taking at admission and how many of these were still prescribed on discharge. Electronic prescribing data was obtained from the Royal Derby Hospital, over a period of 52 weeks from April 2017 to March 2018 for all patients over the age of 65 years who were admitted onto the medicine for the elderly wards and subsequently discharged. On admission, the median number of eligible medications was 11 (interquartile range IQR 8 to 15). At the time of discharge, the median number of eligible medications retained since admission was 9 (IQR 6 to 12). This represents a median number of medications that have been removed from the current medication regimen of 2 (IQR 1 to 3, p

Recent years have seen a decline in herbage production and tiller populations in New Zealand's perennial ryegrass (Lolium perenne) dairy pastures. One hypothesis is that modern genotypes are less suited to the warmer, drier weather experienced under changing climate patterns. In this study, a combination of long‐term trial data (2011–2017) and a process‐based pasture model (BASGRA) was used to explore the causes and possible mitigation of the observed production and population loss at three sites (dryland sites in Northland and Waikato and an irrigated site in Canterbury). Bayesian calibration was used to identify the model parameter sets that were consistent with the trial data and to identify differences in plant morphology and responses between sites. The model successfully simulated the observed differences in tiller numbers between the dryland sites, where populations and production declined rapidly after the second year and the irrigated site where populations and production were maintained. Analysis of the model calibrations along with preliminary scenario simulations suggests that increased tiller mortality associated with drought was the main cause of persistence failure at the dryland sites and that decreasing grazing pressure or breeding for tolerance to higher temperatures may not be successful in preventing this.

Parts of Northern Albania are still hard to get to, but adventure tourism has been making significant inroads, year by year, up until 2019. Two entrepreneurial villages, in particular, have led the way. Over 20 guest-houses have already opened, providing accommodation and food to travellers. Information Adapted from ‘Chapter 12: Destination Management: Case Study: Developing Rural Tourism in Northern Albania’. In: Robinson P., Lück M. and Smith S. (eds) Tourism 2nd Edition . CAB International, pp. 274-276. © CAB International 2021

Interpretation of, and commitment to, Corporate Social Responsibility (CSR) differs from country to country, resulting in variances in implementation. It is theorised that these variances originate from organisational and cultural context. There is limited research dedicated to contextual variances of CSR in the meetings industry. As such, the objective of this paper is twofold: first, to understand whether Meeting Planners in America and Western Europe differ in their current and future motives for engaging with CSR. Second, to establish whether the differences in motivation are influenced by their conceptual understanding of CSR or the wider socio-economic and political. The authors analysed over one thousand self-reporting questionnaires from Meeting Planners across the two continents. Results were analysed using un-related t-tests in order to establish if the two groups differ in their underlying motives to engage with CSR. An exploratory factor analysis was used to determine how Meeting Planners conceptualised CSR across the two continents. Results suggests similar strategic motives to engage in CSR. European Meeting Planners identify egoistic motives to engage in CSR. In contrast to America, CSR practice in Europe will change in the future as value-driven motives become prevalent. The paper provides evidence of context as a defining factor in CSR, where ubiquitous constructs of CSR cannot be easily applied to Meeting Planners. The findings demonstrate the incongruent nature of CSR practice. The results advance the application of CSR to Meeting Planner’s practice in both America and Western Europe, re-igniting the definitional debate of CSR within the meetings industry.

Alpha (α)amylase inhibition is an important strategy for controlling blood glucose level. Presently more potent and easily accessible inhibitors are required for managing diabetes. A series of 5-acetyl-2-(arylidenehydrazin-1-yl)-4-methyl-1,3-thiazoles (2a-n) were designed and synthesised in two steps from thiosemicarbazide via thiosemicarbazones. The structures of the compounds were confirmed spectroscopically (UV, FT-IR, 1H-, 13C-NMR and HRMS). Molecular docking studies of the enzyme-inhibitor complex revealed that the most active compounds have better binding with the α-amylase active site as compared to standard acarbose. Compounds 2c and 2e exhibited excellent α-amylase inhibition with IC50 values 4.80 ± 0.07 and 4.79 ± 0.08 µM, respectively, far better than standard acarbose (IC50 = 5.62 ± 0.04 µM). Compounds 2c and 2e have strong calculated binding affinity (-8.1 and -7.9 kcal/mol, respectively) to the enzyme active site endorsing the experimentally observed inhibition. All other compounds also exhibited excellent α-amylase inhibition and in good agreement with the docking results. Importantly, most of the compounds screened by us did not exhibit any haemolysis up to their active concentrations. All compounds were also evaluated for their anti-glycation and anti-oxidant activities. Their results revealed that besides being α-amylase inhibitors the compounds can be used to reduce diabetic complications, as is evident from anti-glycation results.

The combination of [Cu(MeCN)4]TFA·TFAH (TFA = O2CCF3) with Feringa’s phosphoramidite ligand (LA) provides an exceptionally active (0.75 mol %) catalyst for asymmetric conjugate additions of ZnR2 (R = Et and Me at −40 to −80 °C) to enones. Kinetic and other studies of the addition of ZnEt2 to cyclohex-2-en-1-one indicate a transition state stoichiometry composition of (ZnEt2)3(enone)4Cu2(LA)3 that is generated by transmetalation from Et2Zn(enone)2. Catalyst genesis is significantly slower than turnover (which has limited previous attempts to attain useful kinetic data); in the initial stages, varying populations of catalytically inactive, off-cycle, species are present. These issues are overcome by a double-dose kinetic analysis protocol. A rest state of [LACu(Et)(μ-TFA)(μ-{(enone)(ZnEt)2(enolate)})CuLA2]+ (through the equivalence of enolate = enone + ZnEt2) is supported by DFT studies (ωB97X-D/SRSC). Rate-determining ZnEt2(enone)2 transmetalation drives the exceptionally high catalytic activity of this system.

Here we report the discovery that isomers containing two Dewar benzenoid rings are the preferred form for several sizes of cyclacene. The predicted lower polyradical character and higher singlet-triplet stability that these isomers possess compared with their pure benzenoid counterparts suggests that they may be more stable synthetic targets than the structures which have previously been identified.

This chapter examines the role of student guides as mediators between the institutional mission and heritage of their university and visitors to the historic campus. Drawing on a longitudinal study undertaken at two historic universities in the west, the authors establish that a small cadre of elite, competitively-chosen guides at these institutions perform a role of openness and democracy on behalf of the increasingly complex and hybrid modern university. The chapter considers how student guides are able to navigate their own pride at such privileged engagement and how this privilege impacts on tours offered to visitors, where campus tours become a negotiation based on internal and external influences and are constructed and reconstructed according to the imagined or actual demands of different tour groups. By managing risk at the point of employment, and by encouraging free reign in tours, there is limited risk involved to host universities as student guides offer an informed, personalised heritage experience to both domestic and international tourists.

A Bayesian chemistry-assisted hydrograph separation (BACH) approach was developed, based on calibration of a three-component recursive digital filter, that requires monthly water quality data only. This enables BACH to be applied to the large number of rural catchments for which continuous flow records and monthly water chemistry time series exist from ‘state of environment’ monitoring programmes, but little supplementary data required for more sophisticated analysis techniques. As well as estimating fast, medium, and slow flow components, BACH also estimates for each flow component a time-invariant concentration of the chemical tracers chosen, allowing flow path-specific loads to be calculated. The method was demonstrated using 15 years of total phosphorus (TP) and total nitrogen (TN) data from eight mesoscale catchments in the Waikato region of New Zealand’s North Island. Calibration was done separately for three 5-year data periods, and validated against data from the following 5-year period. Flow path separation and concentration predictions were consistent between data periods, indicating that the TP–TN combination contained sufficient information to reliably identify three flow paths in each catchment; an event-response near-surface flow path with high concentrations of both phosphorus and nitrogen, a seasonal shallow groundwater flow path with lower concentrations of TP but high concentrations of TN, and a deeper slower groundwater flow path characterised by generally low concentrations of both TP and TN. Based on this analysis, the catchments were able to be grouped in three hydro-types. This shows that commonly available water quality data can support robust, objective flow separation and nutrient load apportionment, even in the absence of other supporting data, provided appropriate modelling methods are used.

Electrically conducting organic salts, known for over 60 years, have recently demonstrated new abilities to convert waste heat directly into electrical power via the thermoelectric effect. Multiple opportunities are emerging for new structure–property relationships and for new materials to be obtained through synthetic organic chemistry. This review highlights key aspects of this field, which is complementary to current efforts based on polymeric, nanostructured or inorganic thermoelectric materials and indicates opportunities whereby mainstream organic chemists can contribute.1 What Are Thermoelectrics? And Why Use Them?2 Current Organic and Hybrid Thermoelectrics3 Unique Materials from Tetrathiotetracenes4 Synthesis of Tetrathiotetracenes5 Materials and Device Applications6 Future Perspectives

Rare electron-rich 1-(2-{2-[(aryl)methylidene](R-hydrazinyl}-4-methyl-1,3-thiazol-5-yl)ethan-1-ones [ArCH NN(R)C3NS(Me)(COMe); Ar = 2-, 3- or 4-MeOC6H4, R = H, n-C5H11, CH2Ph) were synthesized (70–77%) and characterized (FTIR, HRMS and 1H-/13C NMR spectroscopy). In one case (Ar=3-MeOC4H4, R = H), the structure was verified by single crystal X-ray diffraction. The observed geometries are true minima, based on M06/6–311G(d,p) level DFT calculation comparisons with experimental data. Calculations were used to extract natural bond orbital (NBO) analyses and predicted non-linear optical (NLO) properties. For comparison, calculated UV–Vis absorptions and frontier molecular orbitals (FMO) analysis were computed using TD-DFT/M06/6–311G(d,p) approaches. The NBO analysis concludes that prolonged hyperconjugation and strong ICT exist in all the entitled compounds, which stabilizes the systems and also offers key evidence of charge transfer/NLO properties. Global reactivity parameters revealed chemical hardness in all molecules and efficient electron donating ability. Calculated band gaps (Egap) of 4.41–4.42 eV were realized while the compound, with all species showing high polarizability. The 4-MeOC6H4, -CH2Ph (Ar,R) compound had the highest calculated values of first hyperpolarizability (βtot), 2975.06 (a.u) and second hyperpolarizability ( ) (2.42 × 105). However, our X-ray results suggest that a centro-symmetric space group is favoured, unvalidating second-order NLO properties studies.

Simple enantioselective synthesis of 6,6-disubstituted pentafulvenes bearing chiral pendant hydroxy groups are attained by cascade reactivity using commercially available proline-based organocatalysts. Condensation of cyclopentadiene with the acetyl function of a 1,2-formylacetophenone, followed by cyclization of a resulting fulvene-stabilized carbanion with the formyl group, generates bicyclic chiral alcohols with initial er values up to 94:6. Exceptional enantio-enrichment of the resultant alcohols results upon crystallization – even near racemic samples spontaneously de-racemize. This enables new families of substituted cyclopentadienes that are both enantiomerically and diastereomerically pure to be rapidly attained.

Derivatives of 3,4-ethylenedithiothiophene (EDTT) are reported starting from tetrabromothiophene. Selective 2,5-dilithiation followed by reaction with a range of aldehydes gives diols as mixtures of diastereomers. Only the 2 and 5 positions in thiophene react leaving the 3,4-bromides for further elaboration. The diols are oxidised to their corresponding diketones using activated MnO2. Reaction with 1,2-ethanedithiol, by addition-elimination, provides access to novel monomers for the preparation of conjugated copolymers of 3,4-ethylenedithiothiophene (EDTT). A range of these monomers can be attained by applying the synthesis of a series of ketones applicable to further synthesis of ?-extended thiophene-based organic semiconductors. Finally, this new route was compared to 3,4-ethylenedioxythiophene (EDOT) dialdehyde derivatives synthesised by an alternative to literature chemistry.

The common practice of infrequent (e.g., monthly) stream water quality sampling for state of the environment monitoring may, when combined with high resolution stream flow data, provide sufficient information to accurately characterise the dominant nutrient transfer pathways and predict annual catchment yields. In the proposed approach, we use the spatially lumped catchment model StreamGEM to predict daily stream flow and nitrate concentration (mg L −1 NO 3 -N) in four contrasting mesoscale headwater catchments based on four years of daily rainfall, potential evapotranspiration, and stream flow measurements, and monthly or daily nitrate concentrations. Posterior model parameter distributions were estimated using the Markov Chain Monte Carlo sampling code DREAM ZS and a log-likelihood function assuming heteroscedastic, t-distributed residuals. Despite high uncertainty in some model parameters, the flow and nitrate calibration data was well reproduced across all catchments (Nash-Sutcliffe efficiency against Log transformed data, NSL, in the range 0.62–0.83 for daily flow and 0.17–0.88 for nitrate concentration). The slight increase in the size of the residuals for a separate validation period was considered acceptable (NSL in the range 0.60–0.89 for daily flow and 0.10–0.74 for nitrate concentration, excluding one data set with limited validation data). Proportions of flow and nitrate discharge attributed to near-surface, fast seasonal groundwater and slow deeper groundwater were consistent with expectations based on catchment geology. The results for the Weida Stream in Thuringia, Germany, using monthly as opposed to daily nitrate data were, for all intents and purposes, identical, suggesting that four years of monthly nitrate sampling provides sufficient information for calibration of the StreamGEM model and prediction of catchment dynamics. This study highlights the remarkable effectiveness of process based, spatially lumped modelling with commonly available monthly stream sample data, to elucidate high resolution catchment function, when appropriate calibration methods are used that correctly handle the inherent uncertainties.

Direct numerical evaluation of the real-time path integral has a well-known sign problem that makes convergence exponentially slow. One promising remedy is to use Picard-Lefschetz theory to flow the domain of the field variables into the complex plane, where the integral is better behaved. By Cauchy's theorem, the final value of the path integral is unchanged. Previous analyses have considered the case of real scalar fields in thermal equilibrium, employing a closed Schwinger-Keldysh time contour, allowing the evaluation of the full quantum correlation functions. Here we extend the analysis by not requiring a closed time path, instead allowing for an initial density matrix for out-of-equilibrium initial value problems. We are able to explicitly implement Gaussian initial conditions, and by separating the initial time and the later times into a two-step Monte-Carlo sampling, we are able to avoid the phenomenon of multiple thimbles. In fact, there exists one and only one thimble for each sample member of the initial density matrix. We demonstrate the approach through explicitly computing the real-time propagator for an interacting scalar in 0+1 dimensions, and find very good convergence allowing for comparison with perturbation theory and the classical-statistical approximation to real-time dynamics., 34 pages, 12 figures; more references added

Business reputation, competitive advantage, differentiation, and regulatory adherence are all factors that are pushing corporate social responsibility (CSR) center stage within the international meetings industry. However, attempts to simplify what is essentially a complex and contextual driven movement through certification and guides has created an incomplete understanding of the salient issues; contemporaneously ignoring contextual variables rather than acknowledging these and the impact these variables have on CSR practice and acceptance. The purpose of this article is to explore the contextual debate of CSR adaptation and practice within the meetings sector within a framework of an ecological systems theory. The authors applied a constant comparison process across 90 interview transcripts in order to establish a rigorous audit trail of analysis. Eight practices were identified: Green Technology, Legislation, Transparency and Reliability, Nonfinancial Donations, Workforce, Community Engagement, Supply Chain Management, and Volunteer Labor. These eight practices were then applied to the constructs of an ecological systems model and an exploration of contextual factors was considered. In recognizing a systems approach to CSR there is an acceptance that there is not one best method and that different values, implementation approaches, and evaluation mechanisms of CSR can lead to similar results.

The reaction of excess TMSCl and LiCCl2 Br at low temperature is a technically simple high yield route to TMSCCl2 Br. The latter is a stable source of the dichlorobromomethide carbanion, which undergoes 1,4-addition with cyclic nitroalkenes and (E)-fumarates leading to dichlorocyclopropanes after bromide expulsion. For nitrostyrenes the reaction arrests at the 1,4-addition product. Low temperature NMR spectroscopy studies and DFT calculations suggest the formation of an "ate" species [(nitronate)SiFMe3 ](-) which, upon boil-off of TMSF at 10-20 °C, yields the cyclopropane. DFT calculations also support the experimental differences between fluoride and acetate as promotors.

While analysis of river water quality time series data alone allows observation of means, variances, trends, and seasonality, it cannot elucidate the catchment mechanisms responsible for these observations. Incorporating river flow data into the analysis allows additional insight to be gained into the mechanisms driving water quality change. Twenty-year series of monthly water quality samples were analyzed alongside high-resolution flow records in 26 catchments across the agriculturally dominated Waikato region of New Zealand. Concentration-discharge relationships indicated the importance of near-surface flow paths in transporting nitrogen and non-dissolved phosphorus species from the land into rivers. Dissolved phosphorus, on the other hand, appears to be discharged primarily in deeper groundwater carrying higher concentrations of geogenic origin. Subsequent data stratification was able to explain the origin of nitrate or phosphorus trends in some catchments as being due to either historical or recent land use changes. These results highlight the value of combined analysis of water quality data with river flow records.

Summary Understanding the hydrological and hydrogeochemical responses of hillslopes and other small scale groundwater systems requires mapping the velocity and direction of groundwater flow relative to the controlling subsurface material features. Since point observations of subsurface materials and groundwater head are often the basis for modelling these complex, dynamic, three-dimensional systems, considerable uncertainties are inevitable, but are rarely assessed. This study explored whether piezometric head data measured at high spatial and temporal resolution over six years at a hillslope research site provided sufficient information to determine the flow paths that transfer nitrate leached from the soil zone through the shallow saturated zone into a nearby wetland and stream. Transient groundwater flow paths were modelled using MODFLOW and MODPATH, with spatial patterns of hydraulic conductivity in the three material layers at the site being estimated by regularised pilot point calibration using PEST, constrained by slug test estimates of saturated hydraulic conductivity at several locations. Subsequent Null Space Monte Carlo uncertainty analysis showed that this data was not sufficient to definitively determine the spatial pattern of hydraulic conductivity at the site, although modelled water table dynamics matched the measured heads with acceptable accuracy in space and time. Particle tracking analysis predicted that the saturated flow direction was similar throughout the year as the water table rose and fell, but was not aligned with either the ground surface or subsurface material contours; indeed the subsurface material layers, having relatively similar hydraulic properties, appeared to have little effect on saturated water flow at the site. Flow path uncertainty analysis showed that, while accurate flow path direction or velocity could not be determined on the basis of the available head and slug test data alone, the origin of well water samples relative to the material layers and site contour could still be broadly deduced. This study highlights both the challenge of collecting suitably informative field data with which to characterise subsurface hydrology, and the power of modern calibration and uncertainty modelling techniques to assess flow path uncertainty in hillslopes and other small scale systems.

The reaction pathway for the formation of tetracenes from the diols 1,2-C6H4(CHOHC≡CAr)2 , LiHDMS, CS2 and MeI has been modelled by computational methods at the CBS-QB3 level of theory. Comparison of PhCHOC(=S)YCCPh (Y = S- or SMe) indicates a slight kinetic advantage for the anionic system towards [3,3]-sigmatropic rearrangement [Eact(calc.) 19.7 vs 21.8 kcal mol-1]. Using anthracene-based models, 10-{SC(=O)Y}-4a,10-dihydroanthracene (Y = S- or SMe), allows direct comparison of both syn and anti-manifolds in the neutral vs. anionic Chugaev elimination. Syn elimination of [HSC(=O)S]- is distinctly favoured [Eact(calc.) 11.4 kcal mol-1] vs. syn elimination of neutral methylated HSC(=O)SMe [Eact(calc.) 27.5 kcal mol-1]. The smaller barrier to syn elimination of the anionic leaving group is in accord with the low temperature conditions required for this Chugaev reaction (60 oC) and suggests a general advantage in carrying out Chugaev eliminations in anionic manifolds.

The electrical properties of organic thin films are determined by their chemical constituents and the morphology of the films deposited. In this paper the morphology of vacuum sublimed (7?10-6 mbar) tetrathiotetracene (TTT) thin films is shown to be strongly affected by the thermal deposition temperature (222-350 K) and rate of deposition. Mostly needle-like morphologies are identified by scanning electron microscopy. Optimal TTT purity (a pre-requisite for device preparation via subsequent oxidation) is evidenced by their initially low electrical conductivity. Altering the TTT morphology, by variation of the evaporation parameters, strongly affects this base electrical conductivity. Four probe conductivity measurements and charge extraction by linear increasing voltage methods are used to characterize film electrical properties. In-plane conductivity of up to 7.03?10-5 S/cm is achieved for pure TTT thin films. Subsequent aerial oxidation resulted in a 3.4-fold increase in electrical conductivity.

The Mogao Caves near Dunhuang contain the largest collection of Buddhist art in China and in the last two decades or so have become one of the most heavily visited archaeological sites away from Be...

Substituted chrysenes have been swiftly synthesised by the 6-endo-dig cyclisation of ethynylnaphthalenes using platinum(II) chloride. Cyclisation precursors were directly prepared from commercially available 2-bromoaldehydes in a telescoped synthetic procedure involving a Cannizzaro triggered cascade and subsequent dehydration and desilylation. This short synthetic procedure allows rapid access to derivatives of biologically active molecules with useful electronic properties.

Reaction of elemental sulfur with 2-R1 and 2,8-R1,R2-substituted tetracenes (2) in refluxing DMF affords 5,6,11,12 tetrathiotetracenes (1) in good yields (74–99%) for a range of substituents where R1,R2 are: H,H (a); Me,H (b); MeO,H (c); Ph,H (d); Me,Me (e), iPr,Me (f, iPr = iso-propyl, CHMe2), Me,MeO (g); MeO,MeO (h). The reaction rate is limited only by the solubility of the tetracene (2); 2g–h being both the least soluble and slowest reacting. At partial conversion recovered single crystalline 2g led to its X-ray structure determination. Vacuum deposited (substrate deposition temperature 300 K, pressure 7 × 10−6 mbar, source temperature 500 K) thin films from 1 (of initial 88–99% purity) show final electrical conductivities, σ(in plane) from 1.40 × 10−5 S cm−1 (1g) to 3.74 × 10−4 S cm−1 (1b) for the resultant near pristine films; while 1d proved too involatile to be effectively sublimed under these conditions. In comparison, initially 95% pure TTT (1a) based films show σ(in-plane) = 4.33 × 10−5 S cm−1. The purities of 1a–h are highly upgraded during sublimation. Well defined micro-crystallites showing blade, needle or mossy like habits are observed in the films. The Seebeck coefficients (Sb) of the prepared 1 range from 374 (1c) to 900 (1f) μV K−1 (vs. 855 μV K−1 for identically prepared 95% pure TTT, 1a). Doping of films of 1f (R1 = iPr, R2 = Me) with iodine produces optimal p-type behaviour: σ(in-plane) = 7.00 × 10−2 S cm−1, Sb = 175 μV K−1. The latter's power factor (PF) at 0.33 μW m−1 K−2 is more than 500 times that of the equivalent I2-doped TTT films (1a, R1 = R2 = H), previously regarded as the optimal material for thin film thermoelectric devices using acene radical cation motifs.

Methods for the batch scale up of DABAL-Me3 promoted direct ester to amide synthesis have been demonstrated at 10–100 g scales using a tert-amide model compound. Procedures for 20 g scale couplings in standard laboratory glassware and up to 0.1 kg in industry-standard jacketed glass reactors in near quantitative yields are given. A derivative of the anticancer agent Imatinib (Gleevec) has been synthesized on a 26 g scale (98% yield, >98% purity) establishing DABAL-Me3 as a potential alternative for the synthesis of amides in API scale preparations. Continuous flow methodology provides a method for larger scales (productivities of >50 g h–1). In addition, nitriles were coupled to primary amines and hydrazines with DABAL-Me3, resulting in the clean formation of free amidines (16 examples) and amidrazones.

The asymmetric copper-catalyzed conjugate addition to α-alkylidene cycloalkanones, substituted at their terminal position with aromatic and aliphatic groups, is reported. While high enantioselectivity is reached using chiral phosphoramidite ligands, with R3Al reagents, moderate diastereoselectivity was observed upon hydrolysis of the aluminium enolates. A Grignard reagent also react with high diastereo­selectivity.

The amidoamines (S)-Ar1CONHCHRCH2NHAr2 [Ar1 = o-C6H4SO3H, R = Bn, iBu, iPr; Ar2 = 2,6-iPr2C6H4, 2,6-Et2C6H4, 2,4,6-Me3C6H2] cyclise to (S) 1-aryl-substituted 4,5-dihydro-1H-imidazolinium species with HC(OEt)3 in moderate-to-excellent yields on heating to 150–175 °C (nine examples, four isolated yields of 48 to >97 %). They are attained as their o-C6H4(SO3–)(CO2Et) salts. The latter are readily deprotonated to afford analytically pure (S) 1-aryl-substituted 4,5-dihydro-1H-imidazoles (imidazolines). The purification of the intermediate sulfonate salts is not always necessary, and analytically pure imidazolines are isolated by simple kugelrohr distillation (nine examples, 45–95 %) after basification. Imidazoline alkylation provides a library of (S)-N-alkylimidazolinium salts (23 examples, 74–97 %). As the initially required amidoamines are available in simple one-pot reactions, the overall approach constitutes a rather efficient approach to this useful family of chiral N-heterocyclic carbene (NHC) ligand precursors (effectively three steps from commercial N-Boc-α-amino alcohols; BOC = tert-butyloxycarbonyl).