The role of hydrogen bonding within aggregate formation and CMC: can these properties be predicted by low level computational modelling?

Through this extensive structure–property study we show that critical micelle concentration correlates with self‐associative hydrogen bond complex formation constant, when combined with outputs from low level, widely accessible, computational models. Herein, we bring together a series of 39 structurally related molecules related by stepwise variation of a hydrogen bond donor–acceptor amphiphilic salt. The self‐associative and corresponding global properties for this family of compounds have been studied in the gas, solid and solution states. Within the solution state, we have shown the type of self‐associated structure present to be solvent dependent. In DMSO, this class of compound show a preference for hydrogen bonded dimer formation, however moving into aqueous solutions the same compounds are found to form larger self‐associated aggregates. This observation has allowed us the unique opportunity to investigate and begin to predict self‐association events at both the molecular and extended aggregate level.

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For over half a century, zeolites have played a major role in the development of modern processes in the chemical and petroleum industries. [1] Their unique combination of physical and chemical properties are ideal for catalysis and separations for a broad range of molecules. Recent advances in zeolite synthesis have centered on high silica zeolite systems or have employed exotic templates. [2] However, low Si/Al ratio zeolites are particularly attractive because they can offer high acid site density for catalytic applications and greater ion-exchange capacity and compositional diversity for separation processes. We report here our discovery of two new zeolite materials, UZM-4 and UZM-5, synthesized at low Si/ Al ratios (Si/Al < 10) by using combinations of two of the most common organic templating agents, the tetramethylammonium (TMA + ) and tetraethylammonium (TEA + ) ions. [3] UZM-4 is a large pore 12-ring zeolite with the BPH framework type [4, 5] and a sufficiently high Si/Al ratio (1.5-2.5) to enable thermal stability. UZM-5 has an unprecedented framework type that contains an 8-ring pore system similar

Herein we report 50 structurally related supramolecular selfassociating amphiphilic (SSA) salts and related compounds. These SSAs are shown to act as antimicrobial agents, active against model Gram-positive (methicillin-resistant Staphylococcus aureus) and/or Gram-negative (Escherichia coli) bacteria of clinical interest. Through a combination of solution-state, gasphase, solid-state and in silico measurements, we determine 14 different physicochemical parameters for each of these 50 structurally related compounds. These parameter sets are then used to identify molecular structure-physicochemical propertyantimicrobial activity relationships for our model Gram-negative and Gram-positive bacteria, while simultaneously providing insight towards the elucidation of SSA mode of antimicrobial action.

For over half a century, zeolites have played a major role in the development of modern processes in the chemical and petroleum industries.[1] Their unique combination of physical and chemical properties are ideal for catalysis and separations for a broad range of molecules. Recent advances in zeolite synthesis have centered on high silica zeolite systems or have employed exotic templates.[2] However, low Si/Al ratio zeolites are particularly attractive because they can offer high acid site density for catalytic applications and greater ion-exchange capacity and compositional diversity for separation processes. We report here our discovery of two new zeolite materials, UZM-4 and UZM-5, synthesized at low Si/ Al ratios (Si/Al < 10) by using combinations of two of the most common organic templating agents, the tetramethylammonium (TMA + ) and tetraethylammonium (TEA + ) ions. [3] UZM-4 is a large pore 12-ring zeolite with the BPH framework type [4, 5] and a sufficiently high Si/Al ratio (1.5-2.5) to enable thermal stability. UZM-5 has an unprecedented framework type that contains an 8-ring pore system similar

Herein, we report the synthesis of a novel amphiphilic salt containing a number of hydrogen bond donating (HBD) and accepting (HBA) functionalities. This amphiphile has been shown to self-associate via hydrogen bond formation in a DMSO solution, confirmed through a combination of NMR, UV-Vis and dynamic light scattering and supported by X-ray diffraction studies. The combination of different HBD and HBA functionalities within the amphiphile structure gives rise to a variety of competitive, self-associative hydrogen bonding modes that result in the formation of 'frustrated' hydrogen bonded nanostructures. These nanostructures can be altered through the addition of competitive HBD arrays and/or HBA anionic guests. The addition of these competitive species modifies the type of self-associative hydrogen bonding modes present between the amphiphilic molecules, triggering the in situ formation of novel hydrogen bonded nanostructures.

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