The palladium-catalysed Suzuki–Miyaura cross-coupling reaction of organohalides and organoborons is a reliable method for carbon–carbon bond formation. This reaction involves a base-mediated transmetalation process, but the presence of a base also promotes competitive protodeborylation. Herein, we established a Suzuki–Miyaura cross-coupling reaction via Lewis acid-mediated transmetalation of an organopalladium(II) intermediate with organoborons. Experimental and theoretical investigations indicate that the controlled release of the transmetalation-active intermediate enables base-independent transmetalation under heating conditions and enhances the applicable scope of this process. This system enables us to avoid the addition of a traditional base and, thus, renders substrates with base-sensitive moieties available. Results from this research further expand the overall utility of cross-coupling chemistry.

Fas (CD95)-Fas ligand (FasL; CD178)-induced apoptosis is necessary for the maintenance of self-tolerance. To clarify whether or not any abnormalities in the Fas-FasL system exist in patients with autoimmune thyroid disease (AITD), we examined the expression of Fas and FasL on peripheral T lymphocytes by three-color flow cytometry in 113 patients with AITD and 49 healthy controls. The intensities of Fas expression in both CD4(+) and CD8(+) T cells decreased in thyrotoxic patients with Graves' disease (GD), but increased in both patients with severe Hashimoto's disease (HD) undergoing treatment and seriously intractable patients with GD continuously positive for thyrotropin (TSH) receptor antibody despite treatment with antithyroid drugs for more than 5 years. The proportion of Fas expression was increased in CD4(+) T cells from patients with untreated GD, and in CD8(+) T cells from patients with severe HD. The proportion of CD8(+) T cells decreased in patients with severe HD. FasL were not expressed on T cells in controls and patients with AITD. These results indicate that (1). the intensities of Fas expression on peripheral T cells increase in severe autoimmune thyroid diseases and (2). both the intensity and the proportion of Fas expression may be important for the induction of apoptosis.

Fluoroalkenes have shown importance as a metabolically stable isostere of amide compounds. To expedite the synthesis of diverse fluoroalkenes, we have developed a dual-reactive C2-unit, (Z)-1-boryl-1-fluoro-2-tosyloxyethene, containing nucleophilic and electrophilic moieties. Consecutive palladium-catalyzed cross-coupling reactions of this unit with aryl bromides and aryl boronic acids allow for the convergent synthesis of diverse trans-1,2-diaryl-substituted fluoroethenes in a chemoselective and stereoretentive manner.

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The palladium-catalysed Suzuki–Miyaura cross-coupling (SMC) reaction of organohalides and organoborons is a reliable method for carbon–carbon bond formation. This reaction involves a base-mediated transmetalation process, but the presence of a base also promotes competitive protodeborylation, which reduces the efficiency. Herein, we established an SMC reaction via Lewis acid-mediated transmetalation of an organopalladium(II) intermediate with organoborons. Experimental and theoretical investigations indicate that the controlled release of the transmetalation-active intermediate enabled base-independent transmetalation under heating conditions and enhanced the applicable scope of this process. This system enabled us to avoid the addition of a base, and thus, rendered substrates with base-sensitive moieties available. Results from this research further expand the overall utility of cross-coupling chemistry.