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The first total synthesis of loroxanthin (1) was accomplished by Horner-Wadsworth-Emmons reaction of C25-apocarotenal 8 having a silyl-protected 19-hydroxy moiety with C15-phosphonate 25 bearing a silyl-protected 3-hydroxy-ε-end group. Preparation of apocarotenal 8 was achieved via Stille coupling reaction of alkenyl iodide 10 with alkenyl stananne 9, whereas phosphonate 25 was prepared through treatment of ally alcohol 23 with triethyl phosphite and ZnI2. The ally alcohol 23 was derived from the known (3R,6R)-3-hydroxy C15-aldehyde 20, which was obtained by direct optical resolution of racemate 20 using a semi-preparative chiral HPLC column.

Bipyridine and related compounds are starting materials or precursors for a variety of valuable substances such as biologically active molecules, ligands for catalysts, photosensitizers, viologens, and supramolecular architectures. Thus, it is important to classify their synthesis methods and understand their characteristics. Representative examples include methods using homo and heterocoupling of pyridine derivatives in the presence of a catalyst. Because bipyridine compounds strongly coordinate with metal centers, a decrease in catalytic activity and yield is often observed in the reaction system. To address this issue, this review provides insights into advances over the last ~30 years in bipyridine synthesis using metal complexes under both homogeneous and heterogeneous conditions. Moreover, strategies for bipyridine synthesis involving sulfur and phosphorous compounds are examined. These alternative pathways offer promising avenues for overcoming the challenges associated with traditional catalysis methods, providing a more comprehensive understanding of the synthesis landscape.

An alternative catalytic strategy for the preparation of benzylmethacrylate esters, key intermediates in the synthesis of coenzyme Q10 and derivatives, was reported. This strategy avoided undesirable stoichiometric reduction/oxidation processes by utilizing the catalytic formation of allylarenes and then cross-metathesis to selectively form E-benzylmethacrylate esters with good yields (58–64%) and complete E-selectivity. The ester intermediates were reduced to common key benzylallylic alcohols (90–92% yield), which were subsequently used in the formal syntheses of coenzyme Q10 and one derivative.

The oxygenated sesquiterpenoid (‐)‐integrifolian‐1,5‐dione, which originates from a plant that finds widespread use in South American traditional medicine, is distinguished by a rigid bicyclic framework consisting of a cyclopropane that is cis‐annulated to a cyclodecane ring. The first total synthesis of this demanding target is described, which relies on a highly selective cyclopropanation reaction of an α‐stannylated‐α‐diazoester catalyzed by a heteroleptic dirhodium paddlewheel complex, followed by an unprecedented Stille‐type cross coupling of the resulting stannylated cyclopropane with methyl iodide as the electrophilic partner to form the all‐carbon quaternary stereocenter at one of the bridgehead positions. Equally decisive was the bicyclization strategy based on lactonization/ring expansion that ultimately allowed the strained ten‐membered carbocycle to be forged. The intricate carbon framework of integrifolian‐1,5‐dione, derived from a plant that is widely used in traditional medicine, combines two formidable challenges: a stiff medium‐sized ring annulated to a cyclopropane at an all‐carbon quaternary chiral bridgehead center. These issues were successfully addressed by an unprecedented strategy based on rhodium catalyzed cyclopropanation/Stille coupling and a bicyclization/ring expansion sequence.

Stille coupling between 5,5′-dibromo-4,4′-diphenyl-2,2′-bithiazole and 9-(2-ethylhexyl)-3-(tributylstannyl)-9H-carbazole in the presence of Pd(Ph3P)2Cl2 in toluene, heated at reflux for 2 h, gave 5,5′-bis[9-(2-ethylhexyl)-9H-carbazol-3-yl]-4,4′-diphenyl-2,2′-bithiazole in 85% yield.

Organic polymer semiconductor materials are conveniently tuned to energy levels because of their good chemically modifiable properties, thus enhancing their carrier transport capabilities. Here, we have designed and prepared a polymer with a donor-acceptor structure and tested its potential as a p-type material for organic field-effect transistor (OFET) applications using a solution-processing method. The conjugated polymers, obtained via the polymerization of the two monomers relying on the Stille coupling reaction, possess extremely high molecular weights and thermodynamic stability. Theoretical-based calculations show that PDPP-2S-Se has superior planarity, which is favorable for carrier transport within the main chain. Photophysical and electrochemical measurements systematically investigated the properties of the material and the energy levels with respect to the theoretical values. The maximum hole mobility of the PDPP-2S-Se-based OFET device is 0.59 cm2 V−1 s−1, which makes it a useful material for potential organic electronics applications.

In this research, two polymers of P1 and P2 based on monomers consisting of thiophene, 3,4-Ethylenedioxythiophene (EDOT) and diketopyrrolopyrrole (DPP) are designed and obtained via Stille coupling polycondensation. The material shows excellent coplanarity and structural regularity due to the fine planarity of DPP itself and the weak non-covalent bonding interactions existing between the three units. Two different lengths of non-conjugated side chains are introduced and this has an effect on the intermolecular chain stacking, causing the film absorption to display different characteristic properties. On the other hand, the difference in the side chains does not have a significant effect on the thermal stability and the energy levels of the frontier orbitals of the materials, which is related to the fact that the materials both feature extremely high conjugation lengths and specific molecular compositions. Microscopic investigations targeting the side chains provide a contribution to the further design of organic semiconductor materials that meet device requirements. Tests based on organic transistors show a slight difference in conductivity between the two polymers, with P2 having better hole mobility than P1. This study highlights the importance of the impact of side chains on device performance, especially in the field of organic electronics.

Organic polymer semiconductor materials, due to their good chemical modifiability, can be easily tuned by rational molecular structure design to modulate their material properties, which, in turn, affects the device performance. Here, we designed and synthesized a series of materials based on terpolymer structures and applied them to organic thin-film transistor (OTFT) device applications. The four polymers, obtained by polymerization of three monomers relying on the Stille coupling reaction, shared comparable molecular weights, with the main structural difference being the ratio of the thiazole component to the fluorinated thiophene (Tz/FS). The conjugated polymers exhibited similar energy levels and thermal stability; however, their photochemical and crystalline properties were distinctly different, leading to significantly varied mobility behavior. Materials with a Tz/FS ratio of 50:50 showed the highest electron mobility, up to 0.69 cm2 V−1 s−1. Our investigation reveals the fundamental relationship between the structure and properties of materials and provides a basis for the design of semiconductor materials with higher carrier mobility.

The Stille coupling reaction is a versatile method to mainly form aromatic CC bonds. However, up to now, the use of palladium catalysts is necessary. Here, a palladium‐free and photocatalytic Stille‐type coupling reaction of aryl iodides and aryl stannanes catalyzing a conjugated microporous polymer‐based phototcatalyst under visible light irradiation at room temperature is reported. The novel coupling reaction mechanism occurs between the photogenerated aryl radical under oxidative destannylation of the aryl stannane, and the electron‐activated aryl iodide, resulting into the aromatic CC bond formation reaction. The visible light‐promoted Stille‐type coupling reaction using the polymer‐based pure organic photocatalyst offers a simple, sustainable, and more economic synthetic pathway toward palladium‐free aromatic CC bond formation. Bye‐bye palladium. A photocatalytic, Pd‐free Stille‐type coupling reaction between aryl iodides and aryl stannanes succeeds using conjugated organic phototcatalysts under visible light irradiation at room temperature.

The development of n-type organic semiconductor materials for transporting electrons as part of logic circuits is equally important to the development of p-type materials for transporting holes. Currently, progress in research on n-type materials is relatively backward, and the number of polymers with high electron mobility is limited. As the core component of the organic field-effect transistor (OFET), the rational design and judicious selection of the structure of organic semiconductor materials are crucial to enhance the performance of devices. A novel conjugated copolymer with an all-acceptor structure was synthesized based on an effective chemical structure modification and design strategy. PDPPTT-2Tz was obtained by the Stille coupling of the DPPTT monomer with 2Tz-SnMe3, which features high molecular weight and thermal stability. The low-lying lowest unoccupied molecular orbital (LUMO) energy level of the copolymer was attributed to the introduction of electron-deficient bithiazole. DFT calculations revealed that this material is highly planar. The effect of modulation from a donor–acceptor to acceptor–acceptor structure on the improvement of electron mobility was significant, which showed a maximum value of 1.29 cm2 V−1 s−1 and an average value of 0.81 cm2 V−1 s−1 for electron mobility in BGBC-based OFET devices. Our results demonstrate that DPP-based polymers can be used not only as excellent p-type materials but also as promising n-type materials.