Detailed mechanistic studies on the coupling of aryl halides with thiols catalyzed by palladium complexes of the alkylbisphosphine ligand CyPF- t Bu ...(1-dicyclohexylphosphino-2-di-tert-butylphosphinoethylferrocene) are reported. The elementary steps that constitute the catalytic cycle, i.e. oxidative addition, transmetalation and reductive elimination, have been studied, and their relative rates are reported. Each of the steps of the catalytic process occurs at temperatures that are much lower than those required for the reactions catalyzed by a combination of palladium precursors and CyPF- t Bu. To explain these differences in rates between the catalytic and stoichiometric reactions, studies were conducted to identify the resting state of the catalyst of the reactions catalyzed by a combination of Pd(OAc)2 and CyPF- t Bu, a combination of Pd(dba)2 and CyPF- t Bu, or the likely intermediate Pd(CyPF- t Bu)(Ar)(Br). These data show that the major palladium complex in each case lies off of the catalytic cycle. The resting state of the reactions catalyzed by Pd(OAc)2 and CyPF- t Bu was the palladium bis-thiolate complex Pd(CyPF- t Bu)(SR)2 (R = alkyl or aryl). The resting state in reactions catalyzed by Pd2(dba)3 and CyPF- t Bu was the binuclear complex Pd(CyPF- t Bu)2(μ2,η2-dba) (9). The resting states of reactions of both aromatic and aliphatic thiols catalyzed by Pd(CyPF- t Bu)(p-tolyl)(Br) (3a) were the hydridopalladium thiolate complexes Pd(CyPF- t Bu)(H)(SR) (R= alkyl and aryl). All these palladium species have been prepared independently, and the mechanisms by which they enter the catalytic cycle have been examined in detail. These features of the reaction catalyzed by palladium and CyPF- t Bu have been compared with those of reactions catalyzed by the alkylbisphosphine DiPPF and Pd(OAc)2 or Pd(dba)2. Our data indicate that the resting states of these reactions are similar to each other and that our mechanistic conclusions about reactions catalyzed by palladium and CyPF- t Bu can be extrapolated to reactions catalyzed by complexes of other electron-rich bisphosphines.
Don Patinkin (1922-1995) was both an eminent theoretical economist and a great historian of economic thought. In the latter field, his focus was on Keynes' "principle of effective demand" from ...Chapter 3 of the General Theory. Having submitted a first interpretation of the "principle" in 1976 - in which he claimed that it contains major flaws - Patinkin revisited the subject several times over the next couple of years. In this process, his interpretation changed markedly. The aim of this paper is to trace (and to comment on) the evolution of Patinkin's interpretation of the theory of effective demand.
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BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
A copper‐catalyzed coupling of aryl, heteroaryl, and vinyl iodides with α‐silyldifluoroamides is reported. The reaction forms α,α‐difluoro‐α‐aryl amides from electron‐rich, electron‐poor, and ...sterically hindered aryl iodides in high yield and tolerates a variety of functional groups. The aryldifluoroamide products can be transformed further to provide access to a diverse array of difluoroalkylarenes, including compounds of potential biological interest.
Double the eFFect: A copper‐catalyzed coupling of aryl, heteroaryl, and vinyl iodides with α‐silyldifluoroamides is reported. The reaction forms α,α‐difluoro‐α‐aryl amides from electron‐rich, electron‐poor, and sterically hindered aryl iodides in high yield and tolerates a variety of functional groups. The aryldifluoroamide products can be further transformed to provide access to a diverse array of difluoroalkylarenes. TMS=trimethylsilyl.
We show that the ring of invariants in a skew monoid ring contains a so called standard Galois order. Any Galois ring contained in the standard Galois order is automatically itself a Galois order and ...we call such rings principal Galois orders. We give two applications. First, we obtain a simple sufficient criterion for a Galois ring to be a Galois order and hence for its Gelfand-Zeitlin subalgebra to be maximal commutative. Second, generalizing a recent result by Early-Mazorchuk-Vishnyakova, we construct canonical simple Gelfand-Zeitlin modules over any principal Galois order.
As an example, we introduce the notion of a rational Galois order, attached an arbitrary finite reflection group and a set of rational difference operators, and show that they are principal Galois orders. Building on results by Futorny-Molev-Ovsienko, we show that parabolic subalgebras of finite W-algebras are rational Galois orders. Similarly we show that Mazorchuk's orthogonal Gelfand-Zeitlin algebras of type A, and their parabolic subalgebras, are rational Galois orders. Consequently we produce canonical simple Gelfand-Zeitlin modules for these algebras and prove that their Gelfand-Zeitlin subalgebras are maximal commutative.
Lastly, we show that quantum OGZ algebras, previously defined by the author, and their parabolic subalgebras, are principal Galois orders. This in particular proves the long-standing Mazorchuk-Turowska conjecture that, if q is not a root of unity, the Gelfand-Zeitlin subalgebra of Uq(gln) is maximal commutative and that its Gelfand-Zeitlin fibers are non-empty and (by Futorny-Ovsienko theory) finite.
In the realm of intergenerational justice, green constitutionalism underscores the necessity for present generations to make choices that do not jeopardize the capacity of future generations to ...fulfill their needs independently. The climate verdict defending the rights of future generations by the German Federal Constitutional Court (Bundesverfassungsgericht) of March 2021 was a game changer in that regard. For the first time in Germany’s climate litigation, the fundamental rights of future generations were subject to constitutional claim and enforceable. They were no longer just a normative claim. Constitutional courts can be seen as defenders of the fundamental rights of future generations where constitutions include such normative perspectives. While the Court upheld the infringement of the fundamental rights of the adolescent plaintiffs in the future, the representation of not-yet-born generations remains unclear. This article examines how the 2021 German climate verdict and constitutional provisions address the representation and protection of the interests of future generations represented by the plaintiffs concerning climate change on the one hand and discusses the potential of protecting the fundamental rights of not-yet-born future generations. The article considers the implications for intergenerational justice and explores how these legal frameworks provided by the Constitution may contribute to the formulation of sustainable policies aimed at ensuring the long-term well-being of future generations. There is an urgent need to develop an institutional regime where the needs and rights of future generations are being considered and included in decision-making processes.
Purpose
The purpose of this study, a case study, is to present the uniqueness of the only UNESCO-awarded tea consumption tradition worldwide and its implications on the tourism industry by analyzing ...and weighting initializing effects of tea on the regional economy, as well tea tourism-related cultural and social rootings.
Design/methodology/approach
Between 20 July 2020 and 20 August 2020, qualitative interviews have been conducted with regional experts, as well as relevant statistics have been evaluated, cultural and social effects have been analysed and weighted, following two main research questions: can “Tea”, along with its history and tradition, be used effectively for initializing tourism and destination brand management? What kind of instruments are useful for reinforcing authentic tea-oriented destination marketing? In addition, the European Tea Speciality Association (ESTA) supported this research project also with another qualitative interview. Furthermore, two workshops of the Working Group on International Tea Tourism have been used to discuss and reflect the impacts of tea museums and tea consuming traditions as well as the European Tea Research Circle (ETRC).
Findings
Tea and its culture is a strong motive for initializing tourism, as it is linked to cosy ceremonies and social gathering. The brand awareness of the destination “East Frisia” as the “tea destination” of Germany is powerful, and the “East Frisian Tea Ceremony” became a regional social anchor and element of loyalty for tourists and citizens. It is useful and profitable to develop more tea-related authentic evens and products to use this UNESCO award and the positive image of tea ceremonies to strengthen the regional economy.
Research limitations/implications
As the UNESCO award was awarded in 2016, any impacts could only be evaluated for a short period of time.
Practical implications
The specific tea culture in East Frisia has the potential for establishing this region as the most unique region for Tea Tourism in Central Europe. This should be evaluated and developed within additional measurements and programmes. The aim should be a plan for additional mapping and tea-related events and attractions to use this unique heritage for developing sustainable tourism and strengthening the regional hospitality infrastructure.
Social implications
The East Frisian tea culture is empowering people and functions as a harmonic link among the inhabitants of a structurally underdeveloped region. Thus, this habit is a key factor for the stability and pride of the inhabitants, involving citizens and keeping traditions alive.
Originality/value
The combination of a cultural heritage award and a habit for celebrating the consumption of a hot beverage is unique worldwide. Therefore, this analysis is a valuable support for the transfer of applicable knowledge from academia to the industry as well as the first research project about the link between tea consuming heritage and tourism in Europe.
The synthesis of novel pentafluorosulfanyl (SF5)-substituted A4-type porphyrins, their corresponding ZnII– and PdII–metal complexes, A3-, A2B- and AB2-type corroles, BODIPYs, and their dipyrrane ...precursors was studied utilizing commercially available SF5-substituted aryl aldehydes. In addition, the functionalization of SF5-substituted tetrapyrroles was investigated by applying the concept of the nucleophilic aromatic substitution (SNAr) with alcohols and sodium azide onto the pentafluorophenyl moiety of a trans-A2B2-porphyrin and two corrole derivatives with a mixed substitution pattern involving the SF5 group. This allows a fine-tuning of the properties of these macrocycles through a selective and mild introduction of functional groups, giving access to multifunctionalized SF5-substituted porphyrinoids. As an example, one functionalized corrole was further reacted with an azido-substituted BODIPY via the copper(I)-catalyzed 1,3-dipolar cycloaddition yielding the first corrole-BODIPY heterodimer involving the pentafluorosulfanyl group.
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