1849-28-1Relevant articles and documents
Facile one-pot synthesis of diarylacetylenes from arylaldehydes: Via an addition-double elimination process
Chen, Jianyang,Zhang, Xuan,Wu, Jiajun,Wang, Rui,Lei, Chunlin,An, Yanan
, p. 4701 - 4705 (2021/06/11)
A practical one-pot protocol has been developed to synthesize diarylacetylenes from arylaldehydes by treatment with 1-(arylmethyl)benzotriazoles and LiN(SiMe3)2. The reaction proceeded through imine formation, Mannich-type addition and double elimination to deliver products in up to 99% yields with broad substrate scope. In addition, gram-scale synthesis of 1-bromo-4-(phenylethynyl)benzene has been demonstrated.
Supramolecular photocatalyst of Palladium (II) Encapsulated within Dendrimer on TiO2 nanoparticles for Photo-induced Suzuki-Miyaura and Sonogashira Cross-Coupling reactions
Eskandari, Ameneh,Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Salimi, Mehri
, (2019/08/20)
In this study, synthesis, characterization and catalytic performance of a novel supramolecular photocatalytic system including palladium (II) encapsulated within amine-terminated poly (triazine-triamine) dendrimer modified TiO2 nanoparticles (Pd (II) [PTATAD] @ TiO2) is presented. The obtained nanodendritic catalyst was characterized by FT-IR, ICP-AES, XPS, EDS, TEM, TGA and UV-DRS. The as-prepared nanodendritic catalyst was shown to be highly active, selective, and recyclable for the Suzuki–Miyaura and Sonogashira cross-coupling of a wide range of aryl halides including electron-rich and electron-poor and even aryl chlorides, affording the corresponding biaryl compounds in good to excellent yields under visible light irradiation. This study shows that visible light irradiation can drive the cross-coupling reactions on the Pd (II) [PTATAD] @ TiO2 under mild reaction conditions (27–30?°C) and no additional additives such as cocatalysts or phosphine ligands. So, we propose that the improved photoactivity predominantly benefits from the synergistic effects of Pd (II) amine-terminated poly (triazine-triamine) dendrimer on TiO2 nanoparticles that cause efficient separation and photogenerated electron–hole pairs and photoredox capability of nanocatalyst which all of these advantages due to the tuning of band gap of catalyst in the visible light region.
The Direct Conversion of α-Hydroxyketones to Alkynes
Ghiringhelli, Francesca,Nattmann, Lukas,Bognar, Sabine,Van Gemmeren, Manuel
, p. 983 - 993 (2019/01/24)
Alkynes are highly important functional groups in organic chemistry, both as part of target structures and as versatile synthetic intermediates. In this study, a protocol for the direct conversion of α-hydroxyketones to alkynes is reported. In combination with the variety of synthetic methods that generate the required starting materials by forming the central C-C bond, it enables a highly versatile fragment coupling approach toward alkynes. A broad scope for this novel transformation is shown alongside mechanistic insights. Furthermore, the utility of our protocol is demonstrated through its application in concert with varied α-hydroxyketone syntheses, giving access to a broad spectrum of alkynes.
