A new family of cyclometallated gold(III) thiolato complexes based on pyrazine‐centred pincer ligands has been prepared, (C^Npz^C)AuSR, where C^Npz^C=2,6‐bis(4‐ButC6H4)pyrazine dianion and R=Ph (1), C6H4 tBu‐4 (2), 2‐pyridyl (3), 1‐naphthyl (1‐Np, 4), 2‐Np (5), quinolinyl (Quin, 6), 4‐methylcoumarinyl (Coum, 7) and 1‐adamantyl (8). The complexes were isolated as yellow to red solids in high yields using mild synthetic conditions. The single‐crystal X‐ray structures revealed that the colour of the deep‐red solids is associated with the formation of a particular type of short (3.2–3.3 Å) intermolecular pyrazine⋅⋅⋅pyrazine π‐interactions. In some cases, yellow and red crystal polymorphs were formed; only the latter were emissive at room temperature. Combined NMR and UV/Vis techniques showed that the supramolecular π‐stacking interactions persist in solution and give rise to intense deep‐red photoluminescence. Monomeric molecules show vibronically structured green emissions at low temperature, assigned to ligand‐based 3IL(C^N^C) triplet emissions. By contrast, the unstructured red emissions correlate mainly with a 3LLCT(SR→{(C^Npz^C)2}) charge transfer transition from the thiolate ligand to the π⋅⋅⋅π dimerized pyrazine. Unusually, the π‐interactions can be influenced by sample treatment in solution, such that the emissions can switch reversibly from red to green. To our knowledge this is the first report of aggregation‐enhanced emission in gold(III) chemistry.

Whereas the reaction of the gold(iii) pincer complex (C^N^C)AuCl with 1-adamantyl thiol (AdSH) in the presence of base affords (C^N^C)AuSAd, the same reaction in the absence of base leads to formation of aryl thioethers as the products of reductive elimination of the Au-C and Au-S ligands (C^N^C = dianion of 2-6-diphenylpyridine or 2-6-diphenylpyrazine). Although high chemical stability is usually taken as a characteristic of pincer complexes, results show that thiols are capable of cleaving one of the pincer Au-C bonds. This reaction is not simply a function of S-H acidity, since no cleavage takes place with other more acidic X-H compounds, such as carbazole, amides, phenols and malonates. The reductive C-S elimination follows a second-order rate law, -d[1a]/dt = k[1a][AdSH]. Reductive elimination is enabled by displacement of the N-donor by thiol; this provides the conformational flexibility necessary for C-S bond formation to occur. Alternatively, reductive C-S bond formation can be induced by reaction of pre-formed thiolates (C^N^C)AuSR with a strong Brønsted acid, followed by addition of SMe2 as base. On the other hand, treatment of (C^N^C)AuR (R = Me, aryl, alkynyl) with thiols under similar conditions leads to selective C-C rather than C-S bond formation. The reaction of (C^N^C)AuSAd with H+ in the absence of a donor ligand affords the thiolato-bridged complex [{(C^N-CH)Au(μ-SAd)}2]2+ which was crystallographically characterised.

Abslracts • Referate

Creating inclusive and effective learning environments for all children can be extremely challenging. How do teachers recognize the needs of their different children, the dynamics between them and adapt in response? This paper presents work from a doctoral study and aims to investigate the integration of multidisciplinary fields (design, art therapy, and education) to create a design thinking-based framework and toolkit, which can be applied in the classroom setting to enhance teaching and learning experiences for autistic children (children with autism spectrum disorder (ASD)).This paper reports on initial fieldwork (case study) that investigates the design thinking of teachers applying arts practices to support the learning of autistic children, aged 5-6 years old. The case study has been carried out at Marine Park Primary School in the Northeast of England. This paper presents an initial cycle of the case study, which is researcherdriven. Further in the doctoral study ownership transitions from the researcher to the teacher and autistic children. This initial cycle resulted in the development of an arts therapy informed toolkit applied to create immersive learning experiences to address inattention and engagement with instructions and story-based tasks. The toolkit breaks down the lesson plans into more readily comprehensible components and translates tasks and worksheets into an immersive 3D learning experience. Reflections from teacherresearch dialogues are presented that indicate an initial framework for day-to-day design thinking for more inclusive learning.

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