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The direct conversion of specific C−H bonds to C−Si bonds in alkanes or aromatics via catalytic methods has attracted growing research interest. Herein, we report the preparation of a new iridium catalyst supported on a naphthyridine‐based porous organic polymer and its successful application in the dehydrogenative silylation of 2‐arylphenols or alcohol and hydrosilanes to access ring‐fused oxasilacycles. The synthetic method exhibits broad substrate scope and good functional group compatibility while avoiding the use of hydrogen acceptors. In addition, this organic polymer supported iridium catalyst could be easily recovered from the reaction system and reused for at least seven times without apparent deactivation. This research provides new insights for the further design of heterogeneous nanocatalysts and contributes to the synthesis of silicon‐substituted functional molecules. [ABSTRACT FROM AUTHOR]

[Display omitted] • Developing a new palladium-catalyzed nitroarene/nitrile reductive cross-annulation chemistry that facilitates straightforward access to pyrrolo[1,2-a]quinoxaline derivatives. • A range of nitriles are activated as carbon synthons to form intramolecular C N and C C bonds. • The use of environment-friendly water and inexpensive HCOONa/HCOOH as the solvent and hydrogen donors, respectively. • The catalyst is conveniently recycled by filtration and can be reused at least five times without obvious deactivation. Green palladium-catalyzed nitroarene/nitrile reductive cross-annulation chemistry that facilitates straightforward access to pyrrolo[1,2-a]quinoxaline derivatives is described herein. A range of nitriles are activated as carbon synthons to form intramolecular C N and C C bonds using this chemistry. The synthetic protocol has the advantages of broad substrate scope, excellent functional group tolerance, and the use of environment-friendly water and inexpensive HCOONa/HCOOH as the solvent and hydrogen donors, respectively. The catalyst is conveniently recycled by filtration and can be reused at least five times without obvious deactivation. This study offers an important platform for converting bulk chemical motifs into value-added functional frameworks. [ABSTRACT FROM AUTHOR]

Objectives: Objectives Pseudohypoparathyroidism type 1A (PHP1A) is caused by maternal inheritance of GNAS mutations. It is characterized by the resistance to several hormones, primarily the parathyroid hormone (PTH), and the features of Albright's hereditary osteodystrophy. Case presentation: Here, we present a family comprised two affected brothers with PHP1A and identify a novel mutation (c.277C>T) in the GNAS gene. The siblings developed a slightly different presentation in the same clinical condition. Although both patients presented with PTH resistance, which is the hallmark of PHP, the proband showed the thyroid-stimulating hormone resistance with the progression of heterotopic ossification from skin and subcutaneous tissue into deep connective tissue, while the younger brother with normocalcemia did not show the resistance to other hormones. The patients may inherit the mutation from their mother who presumably carries the mutation as a mosaicism. Conclusions: Our case highlights the significance of considering mosaicism as an explanation for apparent de novo cases of pseudohypoparathyroidism. [ABSTRACT FROM AUTHOR]