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Two decarboxylative methods providing access to N-alkylated α-trihalomethylated heterocyclic amines have been developed. A batch protocol in which methyl trifluoroacetate acts both as a methylating reagent and subsequently as a nucleophilic trifluoromethyl anion precursor upon its addition to (iso)quinoline derivatives. Next, a telescoped continuous flow process, forming the corresponding α-tri...
“IS IT TOO MUCH TO HOPE that a system of education may some day be devised, which shall give results, in terms of human development, commensurate with the time, money, energy and devotion expended? In such a system of education it may be that mescaline or some other chemical substance may play a part by making it possible for young people to “taste and see” what they have learned about at secon...
A novel synthetic approach to functionalized indolo[2,3-a]quinolizidines is developed via an N-heterocyclic carbene (NHC)-catalyzed annulation of cyclic β-enamino esters with enals . This methodology offers a pathway for quick and efficient construction of an indolo[2,3-a]quinolizidine skeleton which is a core structure of many natural products with diverse bioactivities.
Magnetoresistance and rectification are two fundamental physical properties of heterojunctions and respectively have wide applications in spintronics devices. Being different from the well known various magnetoresistance effects, here we report a brand new large magnetoresistance that can be regarded as rectification magnetoresistance: the application of a pure small sinusoidal alternating-curr...
This paper outlines a practical approach to assist physiotherapists to interpret the results of diagnostic or screening tests. Diagnostic tests are used during clinical assessment to increase or decrease the clinician's estimate of the likelihood that a client has a particular condition. A negative result for a test that is 100% sensitive can rule a condition out (SnOUT), and a positive result ...
The importance of unsymmetrical N-heterocyclic carbenes (uNHCs) as ligands in metal-catalyzed reactions is undeniable. While uNHCs show similar properties as compared with symmetrical NHCs, dissymmetrization allows for further fine-tuning. The introduction of chelatization, hemilability, bifunctionality, shielding effects, and chirality-transfer influences the catalyst's stability, reactivity, ...
Alkoxide-functionalized N-heterocyclic carbenes (NHCs) stabilise the potassium-imidazole-2-ylidene fragment against 1,2 alkyl rearrangement reactions; this allows the first structural characterisation of a potassium NHC complex, which reveals distorted and unusual bonding interactions between the imidazole ring and the potassium cation.
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