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3-Azabicyclo[3.1.0]hexanes are common structural components in natural products and bioactive compounds. Traditionally, the metal-mediated cyclopropanation domino reaction of chain enzymes is the most commonly used strategy for the construction of this type of aza[3.1.0]bicycle derivative. In this study, a base-promoted intramolecular addition of alkenes used to deliver conformationally restricted highly substituted aza[3.1.0]bicycles is reported. This reaction was tailor-made for saturated aza[3.1.0] bicycle-containing fused bicyclic compounds that may be applied in the development of concise and divergent total syntheses of bioactive compounds. [ABSTRACT FROM AUTHOR]

• A FFCA model considering the stampede accidents on inclined staircases is proposed. • Stampede phenomena are based on crowd forces, slopes, and derived probabilities. • The arching, clogging and pedestrian domino effect were observed and analyzed. • The effects of unbalance and stampede of pedestrians on evacuation was revealed. • Certain supplements are made to the research in existing stampede incidents. An extended floor field cellular automata (FFCA) model considering the stampede accidents on inclined staircases is proposed to study shoving behavior and pedestrian dynamics. In this model, two stampede evolution pathways are investigated: Pedestrians falling after losing balance, and falling directly due to being crowded. The results show that this model could trigger some characteristics of real irrational evacuation processes, such as: (1) the mutual crowding and shoving among pedestrians; (2) the unbalance phenomenon on inclined staircases; (3) the effect of pedestrians falling like dominoes, which is consistent with the findings of most stampede investigations to some extent. The proposed model considers the impact of fallen pedestrians on the movement of ordinary pedestrians, which shows a reduction in the overall evacuation efficiency. Moreover, the steeper the slope, the greater the risk and severity of injuries during the crowded evacuation in this scenario. Additionally, falling phenomena of pedestrians show a certain lag related to the state of unbalance. Unbalanced pedestrians tend to appear from the rear to the front successively, and fallings often occur some time later the onset of unbalance, progressing from front to rear. This pattern reflects the "domino effect" among pedestrians. Lastly, unbalanced pedestrians constitute a significant portion of the total injured pedestrians. Considering the time delay of fallings after being unbalanced, the importance of early emergency response and intervention during crowded evacuations is emphasized. It is expected to provide some theoretical support for safety management. [ABSTRACT FROM AUTHOR]

Based on social learning theory and the trickle-down effects, in which behavioral patterns cascade from one management level to the next (also known as the falling domino effect), we attempt to answer whether upper-level managers' temporal leadership can be transferred to lower-level managers to form their temporal leadership, and what the mediating mechanisms and boundary conditions for this occurrence are. By analyzing the data from 234 middle-level managers and 686 junior managers/employees, we found that top managers' temporal leadership was positively associated with middlelevel managers' temporal leadership through the mediating role of middlelevel managers' temporal leadership perspective and that the relationship was moderated by middle-level managers' identification with the top manager. Identification with the top manager, in particular, strengthens both the top manager's positive effect on middle-level managers' temporal leadership and the top manager's temporal leadership's mediating role in this relationship through their temporal leadership perspective. The theoretical and managerial implications of these findings are investigated. [ABSTRACT FROM AUTHOR]

The recent US emphasis on a geoeconomic confrontation with China in the developing states could spawn an economic version of the domino theory. Geoeconomic domino theory assumes that if Beijing's economic influence is not stopped in a developing state, America might witness more developing states incorporated into the Chinese economic orbit. The falling economic domino eventually can reach the developed economies. Nonetheless, there are reasons to expect that the developing economies would not fall to China one after another. China's gains in the developing regions in material capacity, ability to govern key issue areas, and ideological appeal are also dubious. In conducting geoeconomic competition with China, the United States should concentrate on the developed economies—Western Europe and Northeast Asia—that have a significant impact on the balance of power. [ABSTRACT FROM AUTHOR]

Chemical industrial park (CIP) is a typical accident-prone safety-critical system, which is usually congested with high-density hazardous installation units. Domino effects triggered by natural hazards are one of the emerging threats in CIPs, imposing tremendous challenges on society, environment, and economy. This work focuses on analysing the evolution mechanism of natural hazard-induced domino chain (NHDC) from a macro-systematic perspective. Based on the disaster chain theory and the thought of system science, a disaster chain evolution system (DCES) is developed to clarify the accident propagation characteristics. Inspired by the multi-source multi-level propagation pattern of NHDC, the Na-tech layer, the domino layer and the destruction layer are used to form the specific system structure of DCES. A Markov process-based accident propagation (MPAP) model is proposed to cope with the uncertain and complex accident scenarios associated with the evolution process of NHDC. Through formulating the system response process, the proposed MPAP model can reveal the general law of accident evolution. Finally, a general system dynamic response process of DCES is provided to reveal the propagation law of domino effects triggered by natural disaster from a macro-systematic perspective. [ABSTRACT FROM AUTHOR]

Accessibility of products in online retail is an expected part of the shopper experience journey. Frequent products are not accessible due to non-availability. Introduced by Sheth and Sisodia, the 4A's framework articulates how success in any marketing program depends on four dimensions: Awareness, Acceptability, Affordability, and Accessibility. This article demonstrates how, like dominos fall, marketing investments can fail when the final 4A's stage, Accessibility, is not adequately addressed in online retailing. Surveying more than 2,000 shoppers across five European and Asian countries that encountered a non-available item while shopping online for one of six fast-moving consumer goods categories, the research study examines shoppers' switching behavior when Accessibility has been interrupted in the purchasing stage of the customer journey. The overall goal is to better understand how shoppers change their behavior, and it examines a variety of causes that drive switching behavior, whether it be to switch stores, switch brands, or switch intentions when the item they desired is unavailable. Switching behavior was found to vary greatly among the five countries, but less between categories, and switching was greatly affected by the way shoppers encountered the non-available item. The study concludes with recommendations to address Accessibility both in product availability and shoppers' transaction costs. [ABSTRACT FROM AUTHOR]

Kalasin et al. in their 2021 manuscript discuss using artificial intelligence and wearable sensing clothing.[3] Pham et al. also discuss wearable sensors in extreme heat.[4] Each of these innovations can be linked via telemedicine. Each of the manuscripts in this issues continues to showcase the importance, efficacy, and utility of telemedicine and telehealth in managing health in a wide variety of disciplines. 2023;619(7971): 694-697; doi: 10.1038/d41586-023-02311-3. 3 Kalasin S, Sangnuang P, Surareungchai W. Satellite-based sensor for environmental heat-stress sweat creatinine monitoring: The remote artificial intelligence-assisted epidermal wearable sensing for health evaluation. [Extracted from the article]

Inconsistent beliefs call for revision—but which of them should individuals revise? A long-standing view is that they should make minimal changes that restore consistency. An alternative view is that their primary task is to explain how the inconsistency arose. Hence, they are likely to violate minimalism in two ways: they should infer more information than is strictly necessary to establish consistency and they should reject more information than is strictly necessary to establish consistency. Previous studies corroborated the first effect: reasoners use causal simulations to build explanations that resolve inconsistencies. Here, we show that the second effect is true too: they use causal simulations to reject more information than is strictly necessary to establish consistency. When they abandon a cause, the effects of the cause topple like dominos: Reasoners tend to deny the occurrence of each subsequent event in the chain. Four studies corroborated this prediction. [ABSTRACT FROM AUTHOR]

It is essential for domino game players to have a quick estimate of dominoes' propagation speed without engaging in complicated multi-body dynamics simulation. This research article uses directed dimensional analysis to propose a universal scaling law, v = λ g h f ( δ λ ) , for the speed of domino toppling motion. As an application, two approximate power laws were formulated by curve fitting of both theoretical and experimental data. The fitted power laws, v ∼ δ λ h g , show that the domino propagation speed is proportional to the square root of the domino separation λ, thickness δ, and the reciprocation of the domino height h. The obtained scaling law might not only be useful for players but also help them understand domino toppling energy transfer cascades. [ABSTRACT FROM AUTHOR]

In this article I examine how a state's conflict environment affects the amount of foreign aid it receives. Specifically, conflict in the recipient state's neighborhood can have a wide range of externalities that negatively affect the recipient state, but also the interests of donor countries. I argue that the presence of conflict in a state's region generally leads to an increase in the demand for aid funds and should correlate with an increase in the amount of aid a state receives. I further argue that the degree to which the donor state will increase aid funds to meet this demand depends upon the donor's economic and political interests in the recipient state. [ABSTRACT FROM AUTHOR]

This article, titled "Irreversible Structural Phase Transition in [(9-triptycylammonium) ([18]crown-6)][Ni(dmit)2]: Origin and Effects on Electrical and Magnetic Properties," explores a crystal composed of 9-triptycylammonium, [18]crown-6, and [Ni(dmit)2]− that undergoes an irreversible phase transition at 381 K. The phase transition involves the rotation of [18]crown-6 and rearrangement of [Ni(dmit)2]−, resulting in a change in the magnetic system and a significant increase in conductivity. This rare example of an irreversible phase transition driven by molecular rotation has implications for the development of innovative materials. The artwork on the front cover, designed by J. Manabe, depicts a gear representing [18]crown-6 and falling dominoes symbolizing the reorientation of [Ni(dmit)2]−. [Extracted from the article]

Timber is a two player game played on a directed graph, with a domino on each arc. The direction of an arc indicates the direction its domino can be toppled. Once a domino is toppled, it creates a chain reaction toppling all dominoes along that direction, and the player who topples the last domino wins. A P -position is an orientation of the edges of the graph where the second player can always force a win. A connected graph with a cycle has no P -position, thus Timber is a game studied in trees. We prove that a tree has a P -position if and only if the number of edges is even, which generalizes the existing characterization for paths and improves the performance of the existing algorithm to decide if an oriented tree with an odd number of arcs is a P -position. We contribute to the open problem of determining the number of P -positions of a tree. We compute the number of P -positions of three caterpillar infinite subclasses. Finally, we present a lower bound to the number of P -positions of an arbitrary caterpillar. [ABSTRACT FROM AUTHOR]

The domino effect accidents in process industries pose a severe threat to human life and the environment and have the potential to affect nearby facilities as well. Numerous techniques, such as the Bayesian network, have been used for modelling the domino effect. However, these techniques have inherent limitations. These include the inability to consider complex behaviour of process equipment in combined loading and the time dependency of equipment failure. In the current study, a Generalised Stochastic Petri-net model, called as DOMINO-CSPN, is developed to model domino effect accident likelihood and its propagation pattern. The proposed technique is capable of modelling time-dependent failure behaviour of the process component in combined loading. The results from the model are useful in monitoring process risk. A case study is used to demonstrate the application and effectiveness of the model. The results from the model are compared with the past study of a Bayesian network-based domino effect model. This comparative analysis highlights the unique feature of the model and its relevance as a domino effect risk assessment and management tool. [ABSTRACT FROM AUTHOR]

The safety of the process plant depends on the adequate separation between the assets and the hazardous units, along with the installation of protection devices. Several mathematical approaches have been proposed to reduce the risk of the explosions through the solution of the facility layout problem, but no model has included the design of the safety instrument systems. In this work, a MINLP approach was developed to solve three issues at the same time: the process equipment layout, the facility layout, and the safety instrumented system design. This approach aims to find the optimal facility layout that minimizes the land cost, the pipeline cost, and the lifecycle cost of each safety instrumented system, reducing the risk of explosions and keeping safety as much as possible the plant assets. The model was applied to find the optimal facility layout of ethylene oxide plant for different tolerable risk frequencies. In this way, this approach provides valuable information during the design stage and substantial support for decision-makers. [ABSTRACT FROM AUTHOR]

Major accidents in Western countries, receiving a lot of media attention in the 1970s, are starting point for research into internal and external domino effects in the chemical and petrochemical sectors and clusters. Initially, these reports are published by government institutions and government-related research centres. With the upcoming quantitative risk analyses in the 1970s and 1980s, the so-called ocoloured books', published in the Netherlands, play a prominent role in quantifying these domino effects. Since the mid 1990s, the second European Seveso Directive encourages scientific research on domino effects, shown in substantially growth of academic publications on the topic. Research in Western countries is dominated by risk assessments, probabilities, and failure mechanisms are calculated for the complex phenomenon of domino effects and its consequences. Previous works are closely related to political, official and private decision-making. A transition towards risk management is still in its infancy, A future transition is necessary to understand initial scenarios as starting points for domino effects. In India a wake-up call for domino effects occurs in the mid-1990s. Chinese publications on domino effects in the international scientific press appear from the mid-2000s onwards. Due to a rapid industrialisation, the numbers in China country are over-whelming, versus chemical companies, as versus of many major accidents in this sector. This article will discuss results of research on domino effects, conducted in the period 1966-2018, as well as major determinants of these accident processes. Also present, and future transition in this research domain will be discussed. [ABSTRACT FROM AUTHOR]

A new free carbon radical was obtained in a microwave‐assisted solvothermal reaction of the primary amine (1‐methyl‐1H‐benzo[d]imidazol‐2‐yl)methanamine with FeCl3⋅6 H2O in methanol at 140 °C. Through a combination of crystallography and electrospray ionization mass spectrometry, the reaction process was studied. The longest domino reaction includes 14 steps and forms up to 12 new covalent bonds (9 C−N and 3 C−C bonds) and 3 five‐membered heterocycles. For the first time, the homolytic cleavage of a C−O bond was used to synthesize a triarylmethyl radical. [ABSTRACT FROM AUTHOR]

Abstract Secondary toppling failures have complicated mechanisms. In these instabilities, some natural or manmade external factors motivate and overturn a rock mass. One of the most common types of secondary toppling failures is slide-toe-toppling mode. When a blocky or layered rock mass is overlaid by a soil or weak rock mass, the combination of a toppling failure in the rock at the toe and a circular or non-circular sliding in the soil or weak rock in the top leads to this hybrid failure. In 2015, such failure occurred in north-eastern slope of Daralou copper open pit mine. During this instability, the slope consisted mainly of two 10-m benches and one 4-m semi-bench. Since it was supposed to excavate the slope to the depth of 54 m, experts were worried about the project facing a similar larger failure in the future. Hence, a widespread investigation was carried out on the failure. Firstly, the mechanism of this instability was clarified with geological and geotechnical surface and subsurface investigations. Next, existing analytical solution which had been presented for analysis of static slide-toe-toppling failure was modified and some new equations were obtained for analysis of the failure under dynamic condition. Then, a computer code was developed based on the new equations for evaluation of the instability. In the next step, the failed slope was analyzed using the code and finite element method, and outcomes of these analyses were compared with real conditions. The comparison showed that there was satisfactory agreement between the analytical, numerical and actual results. Therefore, these methods were used to predict the behavior of the final slope in static and dynamic conditions. These evaluations indicated that if displaced materials are completely excavated and removed from the mine and overall dip of the slope is reduced, the final slope will be stable against slide-toe-toppling failure. This paper summarizes the results and concludes that both the modified analytical approach and finite element method are able to analyze a slope against the secondary toppling mode. Furthermore, the research proves that re-sloping and unloading are two adequate methods which can be used for stabilization of the failure. Highlights The highlights of this research can be summarized as follows: • Some new equations are presented for pseudo-static analysis of slide-toe-toppling failure. • A new windows form code is developed for analysis of all toppling modes on the basis of theoretical analyses. • A real slide-toe-toppling failure is evaluated with both the new developed and presented code and finite element method via PHASE2. • Results of these methods are compared with real condition. • Final format of the slope is design with mentioned code and finite element method. [ABSTRACT FROM AUTHOR]

Proximity effects permit C–H activation reactions without directing groups. Here competitive reactions of selected substrates were investigated which allow a domino‐carbopalladation/Mizoroki–Heck reaction and a domino‐carbopalladation/C–H activation reaction. In the Pd‐catalyzed transformation of the enantio‐ and diastereopure alkyne 8a the tetra‐substituted alkenes 10 and 11 were formed almost exclusively through a domino carbopalladation/Mizoroki–Heck reaction. In contrast, the diastereomer 8c only led to the acenaphthylenes 12c and 13c through a domino carbopalladation/C–H activation reaction. Moreover, in the reaction of 20, 24 and 27 containing a naphthyl moiety only the tetra‐substituted alkenes 23, 25/26 and 28/29, respectively were obtained, whereas in the reaction of 34, containing a phenanthrene moiety, compound 37 was the only product, formed via a C–H activation reaction. Proximity effects allow C–H‐activation reactions without directing groups in competition with domino‐carbopalladation or Mizoroki–Heck reactions. Vinly–Pd species can be assumed as intermediates, which either react with a double bond or a naphthyl or phenanthryl moiety. [ABSTRACT FROM AUTHOR]

The reaction of N -methylspiro[anthracene-oxazolidine] with spiro[cyclopropane-3,3′-indolin]-2-ones in the presence of MgI 2 formed the corresponding spiro[pyrrolidine-3,3′-indolin]-2-ones in 42–65% yields. The use of N -benzylspiro[anthracene-oxazolidine] in this reaction led to the formation of a mixture of the corresponding N -methyl- and N -benzylpyrrolidines. [ABSTRACT FROM AUTHOR]

Abstract: Historical data analysis shows that escalation accidents, so‐called domino effects, have an important role in disastrous accidents in the chemical and process industries. In this study, an agent‐based modeling and simulation approach is proposed to study the propagation of domino effects in the chemical and process industries. Different from the analytical or Monte Carlo simulation approaches, which normally study the domino effect at probabilistic network levels, the agent‐based modeling technique explains the domino effects from a bottom‐up perspective. In this approach, the installations involved in a domino effect are modeled as agents whereas the interactions among the installations (e.g., by means of heat radiation) are modeled via the basic rules of the agents. Application of the developed model to several case studies demonstrates the ability of the model not only in modeling higher‐level domino effects and synergistic effects but also in accounting for temporal dependencies. The model can readily be applied to large‐scale complicated cases. [ABSTRACT FROM AUTHOR]

A variety of novel heteroannulated pyrano[3,2- c ]quinolines 2 – 12 was efficiently synthesized via a domino ‘ Michael /retro- Michael /nitrile addition/heterocyclization’ reactions between 6-ethyl-5,6-dihydro-4,5-dioxo-4 H -pyrano[3,2- c ]quinoline-3-carbonitrile ( 1 ) and a diversity of carbon nucleophilic reagents. Pyrido[3′,2′:5,6]pyrano[3,2- c ]quinolines 2 – 6 were synthesized from ring opening ring closure reactions of carbonitrile 1 with some methylene active nitrile namely malononitrile, cyanoacetamide, N -phenylcyanoacetamide, (phenylthio)acetonitrile and ethyl cyanoacetate, respectively. Reactions of carbonitrile 1 with dimer malononitrile and cyanoacetohydrazide showed different behavior producing the novel heteroannulated pyranoquinoline derivatives 7 and 8 , respectively. Treatment of carbonitrile 1 with some methylene active ketones namely acetylacetone, acetoacetanilide, ethyl acetoacetate and ethyl benzoylacetate afforded pyrido[3′,2′:5,6]pyrano[3,2- c ]quinolines 9 – 12 , respectively. Structures of the synthesized products were deduced on the basis of their analytical and spectral data. [ABSTRACT FROM AUTHOR]

A mild domino rearrangement strategy for the direct access to substituted quinoline‐4‐carboxamides has been developed. This copper‐catalyzed coupling reaction of O‐acyl oximes with isatins in the presence of molecular oxygen as the sole oxidizing agent proceeds through a ring expansion of the isatins through cleavage of the two C–N bonds. [ABSTRACT FROM AUTHOR]

Abstract: A phosphine‐catalyzed domino reaction of allenoate and two molecular α,β‐unsaturated ketone is reported. In particular, this unexpected strategy incorporates [2+4] annulation and subsequent Michael addition into one reaction, thus providing a new access to polysubstituted dihydropyran derivatives in an efficient manner. The reaction optimization outcome reveals that not only the catalyst, but also the experiment parameters including the solvent and temperature play significant roles for the synthesis of the products. This protocol represents a new reaction mode of two basic chemicals involving C−C and C−O bond‐forming process. The present strategy also features the excellent stereoselectivity, broad substrate scope and atom economy. [ABSTRACT FROM AUTHOR]

Abstract: The advent of gold catalysis has transformed hydroxyalkoxylation of alkynes – once a rudimentary, mercury(II)‐, or silver(I)‐catalyzed process limited to structurally simple substrates – into a sophisticated method that has found application in syntheses of highly complex organic molecules. This transformation can further be combined with carbon‐carbon bond‐forming reactions into domino sequences that allow for a considerable increase of molecular complexity within a single synthetic step. Some recent examples of the development and synthetic applications of these reactions are provided. [ABSTRACT FROM AUTHOR]

Abstract: Amino-functionalized SBA-15 (SBA-Pr-NH2) with a pore size of 6 nm has been used as a basic nanocatalyst in the domino one-pot synthesis of quinoxaline derivatives via the four-component reaction of ninhydrin, 1,2-aryl-diamines, malono derivatives, and α-methylenecarbonyl compound using microwave irradiation. The solid basic catalyst plays a significant role in catalysis, and enhancing the rate and yield of the reaction, it can be easily handled and removed from the reaction mixture by simple filtration and also reused several times without substantial loss of reactivity. Moreover, the complexation reaction between quinoxaline as a model ligand and some metal ions including Cd2+, Co2+, Cu2+, Fe3+, Hg2+, Ni2+, Pb2+, and Zn2+ ions was examined spectrophotometrically in DMF solution at 25 °C. The formation constants of the resulting complexes were calculated from the computer fitting of the molar absorbance measurements in different mole ratios. The obtained data indicated that the stability constant of the resulting complexes varied in the following order Pb2+> Hg2+> Cd2+> Ni2+> Cu2+> Fe3+> Zn2+> Co2+.Graphical Abstract: [ABSTRACT FROM AUTHOR]

A highly efficient approach to polysubstituted 2-amino­pyrroles containing a coumarin derivative unit at the 5-position of the pyrrole ring was developed via a novel multicomponent domino reaction of glyoxal monohydrate derivatives, anilines, coumarin derivatives, and malononitrile. This transformation proceeded via an α-amino­ketone as the key intermediate. [ABSTRACT FROM AUTHOR]

An efficient one-pot synthesis of quinazolin-4(3 H )-ones, benzoimidazo[2,1- b ]quinazolin-12(6 H )-ones and imidazo[2,1- b ]quinazolin-5(1 H )-ones via a palladium-catalyzed domino process has been developed. The Pd-catalyzed reactions of 2-azidobenzamides 1 with isocyanides 2 produced quinazolin-4(3 H )-ones 4 at room temperature by a domino Pd-catalyzed cross-coupling/carbodiimide-mediated cyclization. However, as 2-azido- N -(2-bromophenyl)benzamides 1 were used under heating condition in the presence of Cs 2 CO 3 , the benzoimidazo[2,1- b ]quinazolin-12(6 H )-ones 5 were directly obtained by twice Pd-catalyzed domino cyclization. A domino reogioselective 5 -exo-dig intramolecular cyclization reaction of alkynyl-containing azides 6 with isocyanides 2 generated imidazo[2,1- b ]quinazolin-5(1 H )-ones 9 in 74–93% yields in the presence of catalyst Pd(PPh 3 ) 4 and K 2 CO 3 . [ABSTRACT FROM AUTHOR]

Novel pseudo-enantiomeric bifunctional tertiary amine-squaramides modified with long-chained alkoxy or polyfluoroalkoxy groups, have been synthesized. They catalyzed the asymmetric double-Michael cascade reactions of o - N -tosylaminophenyl α,β-unsaturated ketones with α-nitroolefins in carbon dioxide medium at significantly lower pressure (75 bar) and temperature (35 °C), than known less lipophilic catalysts. Both enantiomers of the pharmacologically valuable methoxy-substituted tetrahydroquinoline derivatives can be prepared in moderate to high yield with promising enantioselectivity (up to 98% ee ) under the optimized conditions. [ABSTRACT FROM AUTHOR]

Tetrazolo[1,5- a ]pyrimidines are well recognized and valuable scaffolds in drug discovery. In the current manuscript, we demonstrated AlCl 3 catalyzed synthesis of series of dihydrotetrazolo[1,5- a ]pyrimidines and tetrahydrotetrazolo[1,5- a ]quinazolinones via a modified Biginelli type multi-component reaction of 5-aminotetrazole, aldehyde and diverse active methylene components such as acetophenone/alkylacetoacetates/dimedone. This provides an efficient route to construct highly functionalized dihydrotetrazolo[1,5- a ]pyrimidines and tetrahydrotetrazolo[1,5- a ]quinazolinones directly from readily available starting materials. [ABSTRACT FROM AUTHOR]

In this paper, we disclose a novel strategy for the phosphine-catalyzed cycloaddition/SN2 substitution domino reaction, giving functionalized O-bridged benzoazepine and benzoxazepine derivatives in moderate to good yields. Changing the N-H protecting group of ortho-aminotrifluoroacetophenone derivatives gave different bridged-ring products in one step. [ABSTRACT FROM AUTHOR]

7a-(Methoxycarbonyl)-N-methyl-1,3a,5,6,7,7a-hexahydro-4H-1,4,6-(epiethane[1,1,2]triyl) indene-4,9-dicarboximide has been prepared through a modification of a previous synthetic sequence, in which the benzyloxymethyl hydroxyl protecting group has been replaced by methoxymethyl, to avoid the apparent formation of a benzyl ester derivative as a side product. The overall yield of the new synthetic sequence is comparable to the previous one. Two advantages of the new procedure are: (a) no benzyl ester was formed and (b) a stereoisomeric mixture of syn- and anti-alcohols at the beginning of the synthetic sequence could be separated and the rest of the synthesis could be carried out with the main syn-stereoisomer instead of the corresponding stereoisomeric mixture as it was the case in the previous process. Additionally, several functional 2,8-ethanonoradamantane derivatives have been prepared. [ABSTRACT FROM AUTHOR]

Three types of sulfides bearing a propargyl or an alkynyl moiety have been studied in cyclocarbopalladation/cross-coupling domino palladium-catalyzed sequences. The reactivity of different types of sulfured starting materials has been compared as well as the difference in behavior of these compounds depending on the type of cross coupling ending the domino sequence. It appeared that these cascades were constantly more efficient on the propargyl benzyl thioether. In addition, it has been demonstrated that domino sequences ending with Stille, Suzuki–Miyaura, or Mizoroki–Heck lead efficiently and selectively to the desired cyclized products. Notably, when the introduction of an alkyne is targeted at the end of the cascade, it appeared that the Sonogashira coupling leads every time to the desired cyclic product in the mixture with the product resulting from the direct coupling between the aryl moiety of the substrate and the alkyne used as partner. Finishing the domino sequence with a Stille coupling instead of a Sonogashira one allowed improving significantly the ratio of the mixture in favor of the desired cyclized compound. [ABSTRACT FROM AUTHOR]

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9 H -pyrido[3,4- b ]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y 1 and Y 2 . The methodology is extended for preparing pyrrolo[1,2- a ]-quinoxaline and indolo[1,5- a ]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho -C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. [ABSTRACT FROM AUTHOR]

A new variable strength keeper technique is proposed in this paper for achieving robust, high-speed, and low-leakage dynamic logic gates with carbon nanotube transistors. The strength of keeper is dynamically adjusted depending on the logical state of dynamic node during input evaluation phase in a domino logic circuit. While providing similar noise immunity, the evaluation delay and power-delay product of proposed domino circuits are reduced by up to 13.33% and 13.84%, respectively, as compared to standard domino circuits in a 16 nm carbon nanotube transistor technology. Furthermore, the proposed domino circuits provide up to 77.98% savings in average leakage power consumption as compared to standard domino logic circuits in idle mode. [ABSTRACT FROM AUTHOR]

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N-Vinylpirrolidinone reacts with (E)-ethyl 5-hydroxy-3-(4-oxo-4H-chromen-3-yl) acrylate (1) through a domino reaction similar to that reported reaction for ethyl vinyl ether. Inverse electron demand Diels–Alder (IEDDA)–elimination-IEDDA generates isomeric tetracycles 5 and 6. The assignment of the relative stereochemistry of the products was made by comparing the proton couplings with those obtained by reaction with ethyl vinyl ether. [ABSTRACT FROM AUTHOR]

With 2-hydroxyphenyl-functionalized enaminones and thiophenols as the starting materials, the facile synthesis of 3-sulfenylated chromones has been realized through a KIO3-catalyzed domino reaction of C−H sulfenylation and subsequent C−N-cleavage-based C−O bond formation. The reaction was performed under transition-metal-free conditions in ethyl lactate, a bioavailable ecofriendly medium. [ABSTRACT FROM AUTHOR]

The use of chiral N-heterocyclic carbenes (NHCs) as catalysts in asymmetric synthesis has opened a wide range of applications due to their unique ability to generate reaction intermediates with unusual reactivity patterns that very often involve the reversal of the typical polarity associated with the functional groups present in the starting materials. In this sense, the direct activation of aldehydes or surrogates by these reactive species provides different chemical structures (conjugated Breslow intermediates, azolium enolates and dienolates, or unsaturated acyl azolium cations) which constitute excellent platforms for initiating cascade or domino reactions in the presence of a polyfunctional reagent. 1 Introduction 2 Cascade Reactions Initiated by the Participation of Homoenolate Equivalents 3 Cascade Reactions Initiated by the Participation of Azolium Enolates 4 Cascade Reactions Initiated by the Participation of Dienolate Equivalents 5 Cascade Reactions Initiated by the Participation of α,β-Unsaturated Acyl Azolium Intermediates 6 Summary and Outlook. [ABSTRACT FROM AUTHOR]

Original polycyclic-containing sulfamide compounds have been synthesized through a domino aza-Michael/Michael/aldol condensation sequence. Resolution of the racemic bicyclic sulfamide starting materials to provide enantioenriched structures has also been investigated. [ABSTRACT FROM AUTHOR]

A new domino sequence involving an aza-Prins cyclization and a Friedel–Crafts reaction is reported. The starting materials are N-tosylimines prepared in situ from N-tosylated homoallylamines and derivatives of phenylacetaldehyde. The domino reactions are mediated by Brønsted and Lewis acids and give benzoannelated azabicyclononanes. Many derivatives thereof contain the benzomorphan scaffold and are thus of pharmaceutical interest as analgesics. The method provides a one-step access to substituted benzomorphans from readily available starting materials. The yields are generally good and various substituents are tolerated. [ABSTRACT FROM AUTHOR]

Domino or sequential processes initiated by cleavage of O radicals has led to the conversion of low-cost, readily available substrates into high-profit products. The optimization of these processes by using different activation sources (irradiation with visible light, microwaves, and conventional heating) is described herein, as well as their application to the conversion of carbohydrates, amino acids, peptides, and terpenes into valuable derivatives. [ABSTRACT FROM AUTHOR]

The palladium-catalyzed domino intermolecular C(sp2)-H activation reaction of two aryl iodides was explored. This simple palladium catalytic system showed good activity. [ABSTRACT FROM AUTHOR]

Estra-4,9-diene-3,17-dione, an important pharmaceutical intermediate, was synthesized by a three-step sequence from δ-lactone 1 in 23.4% overall yield. Reaction of δ-lactone 1 and Grignard reagent 2 followed by treatment with Jones reagent resulted in precursor 4. The domino cyclization reaction of 4 with piperidinium acetate gave estra-4,9-diene-3,17-dione. [ABSTRACT FROM AUTHOR]

The mechanism of neuropathic pain after spinal cord injury is complex, and the communication between neurons, glia, and blood vessels in neurovascular units significantly affects the occurrence and development of neuropathic pain. After spinal cord injury, a domino chain reaction occurs in the neuron-glia-vessel, which affects the permeability of the blood-spinal cord barrier and jointly promotes the development of neuroinflammation. This article discusses the signal transduction between neuro-glial-endothelial networks from a multidimensional point of view and reviews its role in neuropathic pain after spinal cord injury. • Treat the neurovascular unit as a whole rather than separate its individual members. • A domino - like chain reaction occurs in the neurovascular unit after spinal cord injury. • The neurovascular unit provides an anatomical basis for the occurrence and development of neuropathic pain after spinal cord injury. [ABSTRACT FROM AUTHOR]

A copper-catalyzed new domino reaction allowed the facile and direct construction of the dibenzo-fused azepinone ring leading to an array of novel small molecules. The co-catalyst, ligand or additive free one-pot method afforded a unique class of functionalized derivatives, one of which showed encouraging PDE4 inhibition in vitro and apoptosis in vivo. [ABSTRACT FROM AUTHOR]

A novel domino reaction for the preparation of non-racemic β-proline derivatives is reported. The addition of a methyl 2-(oxetan-3-yl)acetate titanium enolate to chiral tert -butanesulfinyl ketimines followed by an intramolecular oxetane ring-opening provides the highly-substituted pyrrolidine ring systems with three contiguous stereogenic centers. [ABSTRACT FROM AUTHOR]

A convenient one-pot multicomponent synthetic approach was developed for the synthesis of novel 2-aryl-3-benzoyl-1 H -benzo[ f ]indole-4,9-diones using 2-amino-1,4-naphthoquinone, N -acylmethylpyridinium bromides, and a variety of aromatic aldehydes. [ABSTRACT FROM AUTHOR]

A series of indolyl substituted 1,4,6,7-tetrahydropyrano[4,3- c ]pyrazole derivatives were synthesized via a domino method based on the 1,4:3,6-Dianhydrofructose. The mechanism was proposed and proved by calculation with a density functional theory (DFT), which includes formation of phenylhydrazone, furanone ring opening, Fischer indole synthesis, pyrazole ring closing and a furan ring expansion. In vitro antitumor activity of all synthesized compounds against four human cancer cell lines (MCF-7, EC-109, HGC-27, and PC-3 cell lines) were then evaluated, using MTT assay. We found that most of the compounds were more potent than the positive control 5-fluorouracil. Particularly, compound 4i against HGC-27 and PC-3, 4j against EC-109 cell lines showed three fold greater activity than 5-fluorouracil, respectively. The activity of compounds 4c and 4d against MCF-7 cell line was close to that of doxorubicin. [ABSTRACT FROM AUTHOR]

A free-radical mediated highly ordered radical addition/cyclization/(sp³)C-C(sp³) formation domino reaction is developed. Three new C-C bonds are formed one by one in a mixed system. Furthermore, it represents the first example of cascade C-C bond formation via selective functionalization of α-hydroxyl-C(sp³)-H in fluorinated alcohols. [ABSTRACT FROM AUTHOR]

This review generalizes the data available on heterocyclizations of 3-aroylacrylic acids and their esters, published over the previous 15 years. Multicomponent, cascade, and domino reactions, as well as cycloaddition and electrocyclization reactions involving 3-aroylacrylic acids and their esters have been used to obtain five- and six-membered aromatic and non-aromatic (including chiral) oxygen- or nitrogen-containing monocyclic heterocycles, spiro compounds, as well as condensed bi- and tricyclic systems. [ABSTRACT FROM AUTHOR]