1942-45-6Relevant articles and documents
A highly active, heterogeneous catalyst for alkyne metathesis
Weissman, Haim,Plunkett, Kyle N.,Moore, Jeffrey S.
, p. 585 - 588 (2006)
(Chemical Equation Presented) An alkylidyne molybdenum amide complex is attached to nontoxic, amorphous silica to form a highly active, recyclable heterogeneous catalyst for alkyne metathesis. The catalyst does not undergo alkyne polymerization, can be utilized at a loading of 1 mol% at room temperature, and has shown unprecedented metathesis activity for the homodimerization of 2-propynylthiophene, a substrate that was previously problematic for alkyne metathesis.
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Bauer,D.P.,Macomber,R.S.
, p. 2640 - 2642 (1976)
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Staley,Doherty
, p. 288 (1969)
Selective terminal alkyne metathesis: Synthesis and use of a unique triple bonded dinuclear tungsten alkoxy complex containing a hemilabile ligand
Coutelier, Olivier,Nowogrocki, Guy,Paul, Jean-Francois,Mortreux, Andre
, p. 2259 - 2263 (2007)
The in situ synthesis of new alkyne metathesis catalysts is described, with particular emphasis on the search for tris-alkoxytungsten-based terminal alkyne metathesis. In that context, hemilabile, ether-containing alkoxy ligands have proved to be suitable and have led to the design and use of a sterically hindered hemilable ligand for the synthesis of a well-defined binuclear, triple-bonded W ≡ W complex. This complex is shown to be a highly active and selective catalyst precursor for terminal alkyne metathesis, and allows the unprecedented metathesis of phenylacetylene.
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.
Asymmetric Covalent Triazine Framework for Enhanced Visible-Light Photoredox Catalysis via Energy Transfer Cascade
Huang, Wei,Byun, Jeehye,R?rich, Irina,Ramanan, Charusheela,Blom, Paul W. M.,Lu, Hao,Wang, Di,Caire da Silva, Lucas,Li, Run,Wang, Lei,Landfester, Katharina,Zhang, Kai A. I.
supporting information, p. 8316 - 8320 (2018/06/29)
Complex multiple-component semiconductor photocatalysts can be constructed that display enhanced catalytic efficiency via multiple charge and energy transfer, mimicking photosystems in nature. In contrast, the efficiency of single-component semiconductor photocatalysts is usually limited due to the fast recombination of the photogenerated excitons. Here, we report the design of an asymmetric covalent triazine framework as an efficient organic single-component semiconductor photocatalyst. Four different molecular donor–acceptor domains are obtained within the network, leading to enhanced photogenerated charge separation via an intramolecular energy transfer cascade. The photocatalytic efficiency of the asymmetric covalent triazine framework is superior to that of its symmetric counterparts; this was demonstrated by the visible-light-driven formation of benzophosphole oxides from diphenylphosphine oxide and diphenylacetylene.