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A unified method for direct C4-H halogenation of indoles has been accomplished with the assistance of anthranilic acids as suitable transient directing groups. Exclusive site selectivity (one out of five potential reactive sites) as well as good functional group tolerance was obtained to install three kinds of halogen atoms (Cl, Br and I, respectively) by using inexpensive N-halosuccinimides (NXS) as halogen sources under mild conditions. Taking advantage of the rich functional groups in the product, a diversity of nitrogen-containing heterocycles were facily constructed via one-step late-stage derivations.

This study aims to determine the Effectiveness of the Cooperative Learning Model with Group Advisory Strategy in Mathematics Learning of the Grade VII SMP. This research is pre-experiment with techniques sampling is cluster random sampling. Data collection was carried out using observation sheets of implementation of learning, test results of learning (pretest and posttest), observation sheets of student activities, and student questionnaire responses. The data analysis technique used is descriptive and inferential statistical analysis. The results of descriptive statistical analysis showed: (1) The average score of learning outcomes after learning reaches 80.04 with standard deviation of 8.79, (2) the posttest results show that classical completeness is achieved 91% (3) The average percentage of student activity is 89% (4) the average percentage of students who gave positive response 89%. The results of inferential statistical analysis showed : (1) The average value of students taught using cooperative learning models with the Advisor Group Strategy is greater than completeness, which is 70, and (2) The proportion of classical completeness of learning outcomes after the application of the cooperative learning model with Group Advisors Strategy achieve classical completeness. From the results of this research it can be concluded that cooperative learning models with the Group Advisory Strategy are effectively used in students of grade VII.

An efficient ethylation reaction of phenols was accomplished by using boron triflouride diethyletherate solution as alkyl source at elevated temperatures. The reaction furnished a repertoire of ary...

I consider the housing market problem with weak preferences. In this context, I provide a sufficient condition for weak group strategy proofness; no group of agents can jointly misreport their preferences such that each agent in the group becomes better-off. Using this sufficient condition, I prove that the top trading absorbing sets, top cycles, and highest priority object rules satisfy weak group strategy proofness. Thus, this paper establishes that it is possible to achieve weak group strategy proofness, along with other desirable results, for the housing market problem with weak preferences even though group strategy proofness is incompatible with Pareto efficiency in this setting.

A rhodium-catalyzed C4-selective C-H alkenylation of 3-carboxy-2-pyridones with styrenes has been developed. The carboxylic group at the C3 position works as the traceless directing group, and the corresponding C4-alkenylated 2-pyridones are obtained exclusively with concomitant decarboxylation. Unlike the reported procedures, the exclusive C4 selectivity is uniformly observed even in the presence of potentially more reactive C-H bonds at the C5 and C6 positions. By using this strategy, the multiply substituted 2-pyridone can be prepared via sequential C-H functionalization reactions.

Over the past few decades, regioselective catalytic C-H functionalization has provided an attractive tool for unique retrosynthetic disconnections. The advancement of the directing group strategy in metal catalyzed synthetic transformation has contributed significantly to the incorporation of a wide range of functionalization reactions in both aromatic systems and aliphatic backbones. However, the extensive utilization of these methodologies depends on the ease of removal of the directing group to restore the free functional group. In this review, we have summarised the reported approaches for removing/modifying versatile directing groups.

Aryl nitriles are key structural motifs in numerous important dyes, agrochemicals, natural products and drug molecules. They are also well known as versatile intermediates for the rapid synthesis of diverse organic compounds such as amines, amidines, tetrazoles, aldehydes, amides and carboxylic acids. In recent years, transition metal-catalyzed sp2 C–H bond cyanation has attracted considerable attention and significant progress has been made in this field. As a major advancement in this field, the directing group strategy in transition metal-catalyzed sp2 C–H bond cyanation has contributed significantly to the direct conversion of cheap hydrocarbons to synthetically versatile cyano-containing compounds, which features the advantages of high efficiency, no pre-functionalization of the substrate, low pollution etc. In this minireview with sections classified by the type of different metal-mediated catalytic systems, we mainly focus on catalytic methodologies of transition metal-catalyzed sp2 C–H bond cyanation assisted by a directing group, with emphasis on reaction scopes, limitations and mechanisms. In addition, the future development prospects of this specific field are also introduced.

Aim To maintain the frequency of going out and to improve homebound status among older adults, specific barriers need to be identified. Hence, this study developed a scale to measure barriers to going out. Methods A preliminary study was carried out to collect items for the scale. We conducted semi-structured interviews with five homebound older adults, and created 14 items as a draft barrier scale. The main study included 2273 older adults and their cohabitating family members in rural Japan. For older adults, the questions included demographic characteristics, responses to the draft scale and variables to examine its validity. For family members, the questions included demographic characteristics, their relationship with the older adult and their assessment of their older relative's willingness to go out. We used data from 892 pairs for our analysis. Results We selected nine items through the criterion group strategy, and confirmed the unidimensional structure of the scale through factor analysis. The results showed significant relationships between the scale and older adults' self-efficacy about going out, their health locus of control, the frequency of going out and their reluctance to go out as assessed by family members. We carried out a receiver operating characteristic analysis to determine the scale's cut-off point. Our multivariate analysis showed that the scale had a significantly stronger association with homebound status than with other variables. Conclusion We developed a highly reliable and valid scale on barriers to going out among community-dwelling older adults and confirmed its usability. Geriatr Gerontol Int 2021; 21: 238-244.

Temporary directing groups (TDGs) underpin a range of C-C bond activation methodologies; however, the use of TDGs for the regiocontrolled activation of cyclopropane C-C bonds is underdeveloped. In this report, we show how an unusual ring contraction process can be harnessed for TDG-based carbonylative C-C bond activations of cyclopropanes. The method involves the transient installation of an isocyanate-derived TDG, rather than relying on carbonyl condensation events as used in previous TDG-enabled C-C bond activations.

A second-generation kilogram-scale synthesis of the psychedelic tryptamine psilocybin has been developed. The synthesis was designed to address several challenges first encountered with the scale-up of previously described literature procedures, which were not optimized for providing consistent yield and purity of products, atom economy, or being run in pilot plant-scale reactors. These challenges were addressed and circumvented with the design of the second-generation route, which featured an optimized cGMP large-scale Speeter-Anthony tryptamine synthesis to the intermediate psilocin with improved in-process control and impurity removal over the three steps. Psilocin was subsequently phosphorylated directly with phosphorous oxychloride for the first time, avoiding a tedious and poor atom economy benzyl-protecting group strategy common to all previously described methods for producing psilocybin. In this report, the challenges encountered in a 100 g scale first-generation literature-based synthesis are highlighted, followed by a detailed description of the newly developed second-generation synthesis to provide over one kilogram of high-purity psilocybin under cGMP.

In the past decade, selective C–C and C-heteroatom bond construction through palladium-catalyzed direct C–H bond functionalization has been extensively studied by employing a variety of directing groups. Within this category, direct asymmetric C(sp2)–H and C(sp3)–H activation for the construction of highly enantiomerically enriched skeletons still progressed at a slow pace. This minireview briefly introduces the major advances in the field for palladium-catalyzed direct asymmetric C–H bond functionalization via the directing group strategy., This minireview introduces Pd-catalyzed direct asymmetric C–H functionalization reactions using a directing group strategy.

Multidentate ligands are highly important but difficult to access. Herein we disclose an atom- and step-economic synthesis of highly substituted 1,1'-biisoquinolines by a C-H activation/bididirecting group strategy. Through rational design of a bididirecting group to "N-OH + N-OAc", selective unsymmetrical diannulation with two different alkynes in a one-pot reaction has been achieved for the first time to access unsymmetrical biisoquinolines. Moreover, the resultant biisoquinolines show tunable photoluminescence and serve as aggregation-induced emission (AIE) systems.

This research uses integrating brainstorming method and Business Model Canvas, model is done with brainstorming method. The Canvas Business Model covers nine blocks, Customer Relationships, Key Partners, Value Propositions, Customer Segments, and cash flow, key resources (key resources), key activities (key activities) and cost structures (cost structures). The result of the research shows strategy with Business Model Canvas can effectively and efficiently in determining Rabuk Diang Empowerment Group strategy

Deoxyfluorination is a primary method for the formation of C-F bonds. Bespoke reagents are commonly used because of issues associated with the low reactivity of metal fluorides. Reported here is the development of a simple strategy for deoxyfluorination, using first-row transition-metal fluorides, and it overcomes these limitations. Using CuF2 as an exemplar, activation of an O-alkylisourea adduct, formed in situ, allows effective nucleophilic fluoride transfer to a range of primary and secondary alcohols. Spectroscopic investigations have been used to probe the origin of the enhanced reactivity of CuF2 . The utility of the process in enabling 18 F-radiolabeling is also presented.

In the house allocation model, the literature ( Bade, 2016 ; Zhang, 2019 ) have proven impossibility theorems regarding the compatibility of efficiency, fairness, and group non-manipulability if agents' preferences are unrestricted. Since in many applications not all preferences are possible, this paper examines to what extent these theorems still hold on restricted preference domains. We find that these theorems still hold unless the domains are restricted to have a special tier structure. We present several possibility theorems when the number of objects is restricted or when preference domains are restricted. This paper clarifies how strong the existing impossibility theorems actually are. As corollaries, we clarify the group incentive properties of Random Priority and Probabilistic Serial, the two mechanisms at the center of many studies.

The reductive coupling of alkynes represents a powerful strategy for the rapid synthesis of highly substituted 1,3-dienes. This method has the advantages of high atom and step economy, and readily available substrates. Unfortunately, the intermolecular coupling of unsymmetrical internal alkynes remains extremely challenging due to the difficulty in controlling self-dimerization and cross-coupling, as well as stereo- and regioselectivity. Previous reports are still limited to intramolecular processes or the use of stoichiometric amounts of metal catalyst. Herein, we report that nickel-catalyzed reductive coupling of two unsymmetrical internal alkynes can overcome the above-mentioned limitations by using a hemilabile directing group strategy to control the regioselectivity. A series of synthetically challenging penta-substituted 1,3-dienes are obtained in good yields with high regio- and enantioselectivity (mostly > 20/1 rr, >90% ee)., The reductive coupling of alkynes represents a powerful strategy for the rapid synthesis of highly substituted 1,3-dienes.

The aptameric protective group strategy for the one-step regioselective transformation of aminoglycoside antibiotics was found to be compatible with diverse reagents and reaction conditions. New derivatives of neomycin B were synthesized with regioselectivities of >99%. This result extends the scope of applicability of APGs facilitating access to novel aminoglycoside derivatives.

Late oxidation of hexose based building blocks or the use of uronic acid containing building blocks are two complementary strategies in the synthesis of glycosaminoglycans, the latter simplifiying the later stages of the process. Here we report the synthesis and evaluation of various disaccharide donors-uronic acids and their pyranose equivalents-for the synthesis of heparan sulfate, using an established protective group strategy. Hexose based "imidate" type donors perform well in the studied glycosylations, while their corresponding uronate esters fall short; a uronate ester thioglycoside performs equal to, if not better than, a hexose thioglycoside equivalent.

Nickel-catalyzed transformation of alkene-tethered oxime ethers to nitriles using a traceless directing group strategy has been developed. A series of alkene-tethered oxime ethers derived from benzaldehyde and cinnamyl aldehyde derivatives were converted into the corresponding benzonitriles and cinnamonitriles in 46-98% yields using the nickel catalyst system. Control experiments showed that the alkene group tethered to an oxygen atom on the oximes via one methylene unit plays a key role as a traceless directing group during the catalysis.

Cyclopentenes and indenes are important structural scaffolds in synthetic, medical, and material chemistry. Cyclization of alkynes via remote C-H functionalization is an appealing approach to construct these motifs due to its high efficiency and step-economy. Herein, a traceless directing group strategy was designed to reverse the regioselectivity of radical addition which enabled an unprecedented photocatalytic sulfonylcarbocyclization of terminal alkynes by forming C-C bond on inert C(sp3 )-H bond. It offers a facile access to decorated cyclopentenes and indenes under mild conditions. The resultant products could be converted into a set of valuable molecular scaffolds, including a key intermediate of AM-6226. Mechanistic experiments suggest a radical cascade pathway comprising a Markovnikov-type sulfonylation, 1,5-hydrogen atom transfer, 5-endo-trig cyclization, and β-elimination. This study lays further groundwork for the use of anti-Baldwin 5-endo-trig radical cyclization in rapidly assembling five-membered carbocycles.

Education is changing rapidly. Schools are gradually shifting away from the traditional mode of instruction and toward a more active model of learning, in which students are collaborating on projects in small groups and then sharing their work with the class. Africa cannot afford to be left behind in this change. Though collaborative teaching and learning are quite popular in Africa, its variants/forms, consensus group and cooperative reflective journal writing are not. The effect of collaborative instructional strategies (consensus group and cooperative reflective journal writing) on students' achievement in biology as moderated by verbal ability was determined in this study. Three hundred five senior secondary school II students from two local governments' area within Ibadan Metropolis participated in the study. The Students' Biology Achievement Test (SBAT) and the Students' Verbal Ability Test (SVAT) were the main data collection tools used for this study. Data generated were analysed using Analysis of Covariance (ANCOVA) and Bonferonni post hoc test. Results show that both forms of collaborative instructional strategies improved students' achievement in biology. Results showed that students exposed to the cooperative reflective journal writing achieved more in biology followed by students in the consensus group strategy. Collaborative strategy can be a feasible alternative approach to teaching biology as it fairly addresses issues of interaction in the classroom. This has helped students develop their communication and also improve their socialisation skills in the classroom and beyond.

A Pd(II)-catalyzed cascade synthesis of diverse polycyclic aromatic hydrocarbons via transient directing group strategy has been developed, involving the consecutive arylation, cyclization and aromatization. The efficiency and practicality were demonstrated by wide substrate range, concise synthetic pathway and mild reaction conditions. The subsequent transformations of the benz[a]anthracene core accessed natural bioactive PAH molecules.

Silylmethyl functionalization provides a general and efficient access to diverse organosilanes. The traditional methods for silylmethyl functionalization often involved silylmethylmetals or silylme...

The aim of this article is to present the possibilities of developing logistics services by the PKP CARGO S.A. Group which is the largest rail freight operator in Poland and one of the largest in Europe. PKP CARGO S.A. wishes to enhance its market position, and one of the strategic goals of the company is to take up the function of a logistics operator. The company is predisposed to play this role due to its position in the market and the opportunities for its development. Moreover, it is the economy and the changing freight structure as well as the EU policy in the field of sustainable transport that are conducive to developing the function of a logistics partner. Nevertheless, PKP CARGO is operating in specific business, legal, infrastructural and rolling-stock conditions. This environment is not easy, in certain situations it is even a hindrance, an obstacle to the development of logistics services, none-theless, the company can see wide prospects for such business. Moreover, analysis of the European market shows that rail operators on these markets have been developing in the direction of a logistics partner.

We prove that group strategy‐proofness and strategy‐proofness are equivalent requirements on stable mechanisms in priority‐based resource allocation problems with multi‐unit demand. The result extends to the model with contracts.

The article provides history of setting up the company 'Rostagroexport', one of the biggest producer of dairy produce in Russia. The author shows in detail the evolution of the group strategy development, from aggressive dumping to output of premium produce and offer of exclusive services (sports and recreation) and describes preconditions of their development and conditions of implementation, as well as specific features of designing polar strategies supplementing key lines in the group activity, which are typical of the period of corporate maturity. In its speedy development the group successively passed over from strategy of cost leadership to strategy of vertical integration and differentiation and later to strategy of diversification by minimizing risks, optimizing various business-processes, extending its production and trading potential, creating inter-branch cooperation, including enterprises of agriculture, food industry and trade, sports and tourist sphere, etc. An important place in the article is taken by analyzing rules of doing business, i.e. grounds of efficient management of any enterprise developed by B. Alexandrov, the founder of the group as a result of long experience of developing different corporate businesses and a comparative analysis of 'Rostagroexport' group rules with management principles of other well-known entrepreneurs and their companies. On this basis advantages and shortcomings of their use in management of commercial organizations of a wide sphere of activity were identified. Special attention is paid to study and assessment of such socially important rules of doing business, as 'pay to your employees in good time' and 'motivate people in positive ways'.

The direct functionalization of C–H bonds is among the most fundamental chemical transformations in organic synthesis. However, when the innate reactivity of the substrate cannot be utilized for the functionalization of a given single C–H bond, this selective C–H bond functionalization mostly relies on the use of directing groups that allow bringing the catalyst in close proximity to the C–H bond to be activated and these directing groups need to be installed before and cleaved after the transformation, which involves two additional undesired synthetic operations. These additional steps dramatically reduce the overall impact and the attractiveness of C–H bond functionalization techniques since classical approaches based on substrate pre-functionalization are still more straightforward and appealing. During the past decade, a different approach involving both the in situ installation and removal of the directing group, which can then often be used in a catalytic manner, has emerged: the transient directing group strategy. In addition to its innovative character, this strategy has brought C–H bond functionalization to an unprecedented level of usefulness and has enabled the development of remarkably efficient processes for the direct and selective introduction of functional groups onto both aromatic and aliphatic substrates. The processes unlocked by the development of these transient directing groups will be comprehensively overviewed in this review article., info:eu-repo/semantics/published

A novel manganese-catalyzed C-H activation methodology for selective hydrogen isotope exchange of benzaldehydes is presented. Using D2O as a cheap and convenient source of deuterium, the reaction proceeds with excellent functional group tolerance. High ortho-selectivity is achieved in the presence of catalytic amounts of specific amines, which in situ form a transient directing group.