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Palladium-catalyzed Hiyama coupling of active thioureas via selective C–N bond cleavage is reported. Notably, the new approach employed active thioureas as coupling partners in the presence of arylsilanes to give amides in good yield. Further, this strategy, which utilized CuF2 as a key oxidant and activator, afforded various amide products under mild conditions and an easy to handle procedure without extra base.

A Phased Mission System (PMS) is defined as a system subject to multiple, consecutive and non-overlapping operation phases of tasks during its mission, which is commonly found in complex technological and engineering practices such as aerospace, nuclear and military operations, etc. Over the past few decades, extensive efforts have been devoted to advance the theories, methods, techniques and tools used for reliability analysis of PMS. The general methods include fault tree based combinatorial approaches and Markov chains. In this paper, a success-oriented GO-FLOW method with a new exact algorithm is presented for reliability analysis of multi-phase mission systems. The feasibility and correctness of the extended GO-FLOW method (GFA) for PMS analysis are proved by comparing the results with fault tree analysis based on Sum of Disjoint Products (SDP) generation algorithm for two example case studies. The comparison results show that the GO-FLOW method can be effectively applied for reliability analysis of PMS in a very compact way. Consistent results can be obtained using extended GO-FLOW algorithm when compared to the fault tree analysis.

We for the first time report the efficient construction of novel tetraphenethylene (TPE)-based macrocycles with various mechanofluorochromism (MFC) behaviors involving solid-state molecular motions. We were able to facilely regulate the diverse solid-state molecular motion behaviors of 18–33-membered macrocycles by adjusting the sizes and shapes of the macrocycle rings. Notably, the building of an intermolecular 6-membered ring between two 20-membered fluorinated macrocycles via F⋯F interactions afforded macrocycle 6F-2, which exhibited changes in MFC behaviors that could be rapidly reversed, i.e., within 100 seconds, at room temperature. X-ray structural analysis supported the unique role of fluorinated macrocycles in self-reversible MFC and the emission variation, particularly, in visualization of solid-state molecular motion.

A new class of crown functionalized TPE macrocycles were concisely synthesized. Furthermore, the 13 membered macrocycle 2O-1 exhibited changes in mechanofluorochromism (MFC) behaviors which could be rapidly self-reversible within 310 s at room temperature. These crown functionalized TPE macrocycles can be used as portable detection tools by doping into polymer dimethyl silicone (PDMS) film. Interestingly, the 1O-2 macrocycle film could efficient discriminate benzene from volatile organic compounds through visually fascinating emission color switching from blue to green-yellow. Notably, iodobenzene was different from other halogen benzene (F, Cl, Br), accompanying visibly discernible emission color switching from blue to dark-brown on 1O-2 macrocycle film. Thus, such macrocycle film will be applied as high selection discriminating test strip of benzene derivatives.

A series of shoulder pole-shaped D-A-D molecules were first synthesized by bridging two asymmetrical diphenyl sulfone units with alkynyl linker. Among them, compound ETOSPz displays remarkable white-light emission with thermally activated delayed fluorescence (TADF) and mechanochromic luminescence (MCL) properties. The crystal structure analysis revealed the alterable conformation of phenothiazine, which is identified as a reasonable explanation for MCL behavior. Combined with the theoretical calculation, EtOSPz exhibits a small singlet-triplet splitting energy (ΔEST) which is good for RICS process, and the ΔEST could be modified by introducing an alkynyl linker into two diphenyl sulfones or adjusting substituents on the diphenyl sulfone. Notably, a multifunctional organic white-light TADF material was first developed via linking a alkyne group into two diphenyl sulfones. Importantly, the multifunctional character of diphenyl sulfone could be adjusted by a straightforward linker, which offers a new approach for the development of new optical-electro materials.