Palladium(0)-catalyzed conversion of vinyl trifluoromethanesulfonates into α,β-unsaturated nitriles

Piers, Edward; Fleming, Fraser F.

doi:10.1139/v93-234

Cited by 12 publications

(3 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The installation of a cyano group at the 5-position would lead to a push–pull system that could open new synthetic opportunities including the attack of nucleophiles at C-4. Metal cyanides such as KCN represent synthetically valuable C-1 building blocks that could efficiently be coupled by palladium catalysis to alkenyl triflates [46–47] or alkenyl halides [48–49] forming α,β-unsaturated nitriles. As shown in Scheme 7, we adopted a protocol described by Yamamura and Murahashi [48] and found that the palladium-catalyzed coupling of anti - 4d with potassium cyanide in the presence of 18-crown-6 at 80 °C in toluene afforded the desired 5-cyano-substituted product anti - 25 in moderate yield (not optimized).…”

Section: Resultsmentioning

confidence: 99%

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

Medvecký

Linder

Schefzig

et al. 2016

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

Iodination of carbohydrate-derived 3,6-dihydro-2H-1,2-oxazines of type 3 using iodine and pyridine in DMF furnished 5-iodo-substituted 1,2-oxazine derivatives 4 with high efficacy. The alkenyl iodide moiety of 1,2-oxazine derivatives syn-4 and anti-4 was subsequently exploited for the introduction of new functionalities at the C-5 position by applying palladium-catalyzed carbon–carbon bond-forming reactions such as Sonogashira, Heck, or Suzuki coupling reactions as well as a cyanation reaction. These cross-coupling reactions led to a series of 5-alkynyl-, 5-alkenyl-, 5-aryl- and 5-cyano-substituted 1,2-oxazine derivatives being of considerable interest for further synthetic elaborations. This was exemplarily demonstrated by the hydrogenation of syn-21 and anti-24 and by a click reaction of a 5-alkynyl-substituted precursor.

show abstract

Section: Resultsmentioning

confidence: 99%

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

Medvecký

Linder

Schefzig

et al. 2016

Beilstein J. Org. Chem.

View full text Add to dashboard Cite

show abstract

“…The presence of n Bu 4 NCl, and the use of Xantphos, a rigid bidentate ligand with a wide natural bite angle, was found to be crucial for the success of the reaction (Scheme 50) [69]. Vinyl and aryl cyanides can also be produced by coupling vinyl or aryl triflates with lithium cyanide in the presence of tetrakis(triphenylphosphane)palladium and crown-ether (12-crown-4) (Scheme 51) [70]. Although Pd-catalyzed cross-coupling reactions for C-C bond formation remained the main applications of vinyl and aryl sulfonates, other coupling reactions have been reported.…”

Section: A5) Other Metal-catalyzed Reactionsmentioning

confidence: 99%

Vinyl and Aryl Sulfonates: Preparations and Applications in Total Synthesis

Chassaing

Specklin²,

Weibel³

et al. 2012

COS

View full text Add to dashboard Cite

Vinyl and aryl sulfonates are ubiquitous building blocks in organic chemistry, frequently exploited in the total synthesis of natural and non-natural products, due to their ease of formation and to their high reactivity, especially in metal-catalyzed cross-coupling reactions. The present review thus aims at first describing the classical and current methods to prepare these valuable synthons, with an emphasis on reaction mechanisms. The second part of the review aims at highlighting their main applications in organic synthesis, especially in the course of natural product total syntheses.

show abstract

“…However, the Pd(PPh 3 ) 4 -mediated process is recognized as being notoriously unreliable, thus prompting reports of several modifications to the original protocol. These variations are categorized generally by the application of either modified ligand sets, 2f, the use of covalent ,, and alumina impregnated cyanide sources, or the inclusion of crown ether additives . Additionally, conducting the reaction in the presence of electrochemical reducing potential has been shown to minimize the persistent problem of catalyst deactivation .…”

Section: Introductionmentioning

confidence: 99%

Cooperative Catalyst Effects in Palladium-Mediated Cyanation Reactions of Aryl Halides and Triflates

et al. 1998

View full text Add to dashboard Cite

Substoichiometric quantities of copper or zinc species dramatically improve both conversion rate and efficiency of Pd(0)-catalyzed cyanation reactions. The optimum reaction conditions involve the use of a nitrile solvent, NaCN, and a catalyst system employing the combination of cuprous iodide with tetrakis(triphenylphosphine)palladium(0), [Pd(PPh3)4]. Beneficial effects were observed for the conversion of aryl halides, aryl triflates, and a vinyl bromide to the corresponding nitriles. The process was demonstrated on preparative scale with a broad range of aromatic and heteroaromatic substrates containing diverse functionality. A dual catalytic cycle is proposed to explain the profound influences of the cocatalyst system.

show abstract

Palladium(0)-catalyzed conversion of vinyl trifluoromethanesulfonates into α,β-unsaturated nitriles

Cited by 12 publications

References 15 publications

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

Iodination of carbohydrate-derived 1,2-oxazines to enantiopure 5-iodo-3,6-dihydro-2H-1,2-oxazines and subsequent palladium-catalyzed cross-coupling reactions

Vinyl and Aryl Sulfonates: Preparations and Applications in Total Synthesis

Cooperative Catalyst Effects in Palladium-Mediated Cyanation Reactions of Aryl Halides and Triflates

Contact Info

Product

Resources

About