Selective annulation of benzamides with internal alkynes catalyzed by an electron-deficient rhodium catalyst

1988 ◽

Vol 46 ◽

pp. 946-947

Author(s):

A. Legrouri

Keyword(s):

Aqueous Solution ◽

Thermal Decomposition ◽

Physicochemical Properties ◽

Surface Area ◽

Vanadium Pentoxide ◽

High Purity ◽

Gas Adsorption ◽

Rhodium Catalyst ◽

Optical Methods ◽

Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

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Diastereoselective Reductive Arylation of Internal Alkynes

Synfacts ◽

10.1055/s-0037-1610582 ◽

2018 ◽

Vol 14 (09) ◽

pp. 0955

Keyword(s):

Internal Alkynes

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Ruthenium(II)-Catalyzed Intermolecular Cyclo(co)trimerization of 3-Halopropiolamides with Internal Alkynes

10.26434/chemrxiv.6157613 ◽

2018 ◽

Author(s):

Anthony P. Silvestri ◽

James S. Oakdale

Keyword(s):

Ambient Temperature ◽

Internal Alkynes

<div>A highly chemo- and regioselective cyclo(co)trimerization between 3-halopropiolamides and symmetrical internal alkynes is reported. The reaction is catalyzed by Ru(II)-complexes and proceeds at ambient temperature in ethanol to deliver fully substituted dihalogenated isophthalamides. 1,4-Butynediol was found to undergo spontaneous lactonization with halopropiolamides after trimerization to provide 5,7-dihalo-phthalide products.</div>

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Intermolecular [5+2] Annulation between 1‐Indanones and Internal Alkynes by Rh‐catalyzed C−C Activation

Angewandte Chemie ◽

10.1002/ange.202106007 ◽

2021 ◽

Author(s):

Rui Zhang ◽

Ying Xia ◽

Guangbin Dong

Keyword(s):

Internal Alkynes

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Rhodium-Catalyzed, Phosphorus(III)-Directed Hydroarylation of Internal Alkynes: Facile and Efficient Access to New Phosphine Ligands

Synlett ◽

10.1055/a-1314-0064 ◽

2020 ◽

Author(s):

Minyan Wang ◽

Zhuangzhi Shi ◽

Huanhuan Luo ◽

Dawei Wang

Keyword(s):

High Selectivity ◽

Enantiomeric Excess ◽

Phosphine Ligands ◽

Rapid Construction ◽

Efficient Access ◽

Internal Alkynes ◽

Great Progress ◽

Chiral Phosphine Ligands ◽

Optimized Conditions ◽

Made In

AbstractOrganophosphines are an important class of ligands widely used in organic chemistry. Although great progress has recently been made in the rapid construction of new phosphines through Rh- or Ru-catalyzed C–H bond functionalizations, synthetic access to more diverse phosphines remains a challenge. We describe an efficient process for the rhodium-catalyzed phosphorus(III)-directed hydroarylation of internal alkynes to generate various alkenylated and 2′,6′-dialkenylated biarylphosphines with high selectivity. A range of diverse alkynes and phosphines were effectively prepared with broad functional-group compatibility under the optimized conditions. In addition, the developed protocol can be extended to modify chiral phosphine ligands, providing enantioenriched alkenylated phosphines without erosion of the enantiomeric excess.

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