Water can accelerate a variety of organic reactions far beyond the rates observed in classical solvents. However, using pure water as solvent introduces solubility constraints that have limited applicability efficient photochemistry particular. We report here formation aggregates between pairs arenes, heteroarenes, enamines, or esters with different electron affinities an aqueous medium, leading to oil-water phase boundary through substrate melting point depression. The active hydrogen atoms...

The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes haloarenes with indoles, anilines, anisoles or thiols, which are not observed solvents. UV-A photoinduced transfer within EDA induces mesolytic cleavage halide ion radical recombination arenes leading, after rearomatization proton loss to C-C C-S coupling products. Depending on substitution pattern selective unique cross-couplings observed. UV NMR...

In ion-pair catalysis, the last intermediate structures prior to stereoselective transition states are of special importance for predictive models due high isomerization barrier between E- and Z-substrate double bonds connecting ground state energies. However, in experimental investigations chiral phosphoric acids (CPA) solely early intermediates could be investigated while key remained elusive. this study, first structural conformational insights into ternary complexes with CPAs presented...

Aminophosphates are the focus of research on prebiotic phosphorylation chemistry. Their bifunctional nature also makes them a powerful class organocatalysts. However, structural chemistry and dynamics proton‐binding in organocatalytic mechanisms still not fully understood. Aminophosphine chalcogenides, preserving H2N–P+–Ch− motif, represent well‐suited molecular models that mimic proton‐binding, hydrogen‐bond switching supramolecular self‐assembling behavior catalytically prebiotically...

Aminophosphates are the focus of research on prebiotic phosphorylation chemistry. Their bifunctional nature also makes them a powerful class organocatalysts. However, structural chemistry and dynamics proton‐binding in organocatalytic mechanisms still not fully understood. Aminophosphine chalcogenides, preserving H2N–P+–Ch− motif, represent well‐suited molecular models that mimic proton‐binding, hydrogen‐bond switching supramolecular self‐assembling behavior catalytically prebiotically...

In this work, 1‐butyl‐3‐methylimidazolium tetrafluoroborate/water mixtures were analysed over the whole water composition (x w ) in order to study rotational and translational behaviour of ions. We employed a multinuclear NMR approach determine anion/cation/water diffusion coefficients longitudinal relaxation rates at different content. neat ionic liquids (IL), cation diffuses faster than anion, low x , anions cations share almost same coefficient, but above critical concentration, anion...

An in-depth analysis including NMR-spectroscopy at 180 K and computer simulations suggests an OHN hydrogen bond between the phosphoramide oxygen imine instead of mostly proposed NHN H-bond in binary NTPA/imine complexes.

Photoinduced borylation has emerged as a valuable strategy for synthesizing arylboronic esters. However, photochemical transformations involving inert bonds such C(sp2)−F are still challenging. Herein, we report straightforward and operationally simple method the activation of various carbon−heteroatom bonds, enabling synthesis diverse esters without need transition metals or catalysts. Mechanistic investigations reveal that deprotonation DMSO plays pivotal role in reaction, excited anion...

Abstract We have developed a sequential and selective Pd‐catalyzed double‐Heck arylation of ethylene that results in non‐symmetrical nitro‐stilbene analogs trans ‐resveratrol at excellent yields. A catalytic system consisting Pd(OAc) 2 P( o ‐tolyl) 3 permitted us to carry out the two consecutive Heck arylations without losing activity from first second reaction. After ethylene, no isolation or additional catalyst loading is required for This protocol was applied synthesis methylated...

The comprehensive real-time in situ monitoring of chemical processes is a crucial requirement for the in-depth understanding these processes. This facilitates an efficient design chemicals and materials with precise properties that are desired. work presents simultaneous utilization synergy two novel time-resolved NMR methods, i.e., diffusion nonuniform sampling. first method allows average coefficient products to be followed, while second enables particular monitored. Additionally, mass...

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Abstract The amino alcohol meglumine solubilizes organic compounds in water and enforces the formation of electron donor acceptor (EDA) complexes haloarenes with indoles, anilines, anisoles or thiols, which are not observed solvents. UV‐A photoinduced transfer within EDA induces mesolytic cleavage halide ion radical recombination arenes leading, after rearomatization proton loss to C−C C−S coupling products. Depending on substitution pattern selective unique cross‐couplings observed. UV NMR...

We report herein a simple, yet unexpected approach to dramatically improve the efficiencies of radical fluorination reactions C(sp3)−H bonds. H−TEDA(BF4)2 is readily generated as byproduct during with Selectfluor®, world’s most popular organic reagent. However, date overlooked and discarded waste, despite comprising 95% M.W. Selectfluor®. demonstrate that addition at start markedly increases their rates, outcompeting side access higher overall yields fluorinated products. Showcasing...

The reaction of the Ag(I) dimer [Ag2(η2-A)2(μ,η1:η1-A)2][TEF]2 (A = [{CpMo(CO)2}2(μ,η2-P2)]) possessing labile η2-coordinated P2 ligands with organometallic dipnictogen compounds [{CpMo(CO)2}2(μ,η2-EE')] (E E' As, Sb; E P, Sb) represents a facile synthetic route towards unprecedented heteroleptic pnictogen-rich supramolecular complexes. This method can also be extended to analogous Cu(I) and is studied by DFT computations.

The routine operation phase of a satellite occurs after its launch and initializing settings the in orbit. basic operational functions are operations that include telemetry monitoring, sending remote command implementation tracking measurements, such as range rate, execution procedures, which consists actions taken when task. Currently, area control, there is general interest automating way reducing in-orbit maintenance costs, specially high cost with teams operations. Besides reduction,...

se, atualmente, como um grave problema de saúde pública

In this work, a broad pallete of macroscopically sized samples ionic liquids was used, in which tensions about -100 MPa were obtained preliminary testing methodologies before cavitation would occur. Preliminary NMR studies have been performed on under homogeneous tension. Upon entering into these metastable regimes negative pressure, it is possible to observe sharp increase the anion and cation self-diffusion coefficients as compared equilibrium saturated liquid conditions at identical temperatures.

The various economic changes promoted innovation theory adaptation in order to include services. Therefore, the client was noticed as an important element process. Considering technological advances and changes, Social Networks Sites (SNS) became a new field explore organizations. Following this, this article is proposed identify services based on companies clients interaction through SNS. Thus, quantitative research applied featured by online survey with service organizations Sergipe,...

Abstract This process works without isolation after the first arylation and additional catalyst loading.