Explicit mapping of acoustic regimes for wind instruments

This paper proposes a methodology to map the various acoustic regimes of wind instruments. The maps can be generated in a multidimensional space consisting of design, control parameters, and initial conditions. The boundaries of the maps are obtained explicitly in terms of the parameters using a Support Vector Machine (SVM) classifier as well as a dedicated adaptive sampling scheme. The approach is demonstrated on a simplified clarinet model for which several maps are generated based on different criteria. Examples of computation of the probability of occurrence of a specific acoustic regime are also provided. In addition, the approach is demonstrated on a design optimization example for optimal intonation.     

Combined directed ortho-metalation, remote metalation, and Stille cross-coupling strategies. Concise stereoselective synthesis of polysubstituted 9H-fluoren-9-ones

The new sequential stereoselective synthesis of diversely substituted 9H-fluoren-9-ones by ortho-lithiation/Bu₃SnCl quench of unprotected benzoic acids followed by Stille cross-coupling reaction and remote metalation is reported.     

Synthesis of Polycyclic Aromatic Hydrocarbon‐Based Nanovehicles Equipped with Triptycene Wheels

Two new nanovehicles that have extended aromatic platforms as the cargo zones have been obtained. Two strategies were considered for the formation of the perylene core from two naphthalene precursors. The first was based on a Scholl‐type reaction involving an oxidant, and the second used a brominated derivative to perform a homocoupling reaction. The first strategy failed under diverse coupling conditions in the presence of several strong oxidants. Nevertheless, the use of CoF₃ in trifluoroacetic acid triggered a dimerization reaction between two ester groups of one molecule and the naphthalene unit of another, thereby surprisingly yielding a ten‐membered carbon macrocycle. The second strategy encountered a lack of reactivity of the substrate under several homocoupling conditions. The dimerization was not easily performed but Ullmann‐type conditions ultimately gave the expected product. The low yield and low solubility of the product encouraged us to modify our initial design. The synthesis of a new chassis that incorporated additional tert‐butyl groups improved the solubility of the molecules and also prevented overcyclization of the aromatic platform by blocking these positions. Some p‐phenylene spacers were also intercalated between the iodine and perylene centers to increase the reactivity of the halide towards coupling reactions. Two new chassis were obtained by Scholl‐type oxidative coupling using FeCl₃ as the oxidant. The introduction of four triptycene wheels allowed the formation of the two corresponding nanovehicles.     

NHC-carbene cyclopentadienyl iron based catalyst for a general and efficient hydrosilylation of imines

A general and efficient hydrosilylation of imines catalysed by a well defined NHC-carbene cyclopentadienyl iron complex has been developed. Both aldimines and ketimines are converted to the corresponding amines under mild conditions, and under visible light activation.     

Using small angle scattering (SAS) to structurally characterise peptide and protein self-assembled materials

In the past 20 years protein and peptide self-assembly has attracted material scientists' interest due to the possibility to exploit such molecular mechanism to create novel biomaterials including hydrogels. One of the main challenges when dealing with "soft" biological materials is their structural and morphological characterisation. Small angle scattering (SAS) can be a highly complementary tool to microscopy for the characterisation of such materials as it allows the investigation of samples in their wet-state without the need for any sample preparation such as drying and/or freezing. In this tutorial review we introduce briefly the SAS technique to the non-expert and through selected examples from the literature show how SAS can be readily used thanks to existing analytical approaches developed by a number of authors to extract structural information on the self-assembly of peptide and proteins.