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• 100-46-9 benzylamine 
• 104-54-1 3-Phenylpropenol 
• 68-12-2 N,N-dimethyl-formamide 
• 7217-71-2 1-phenyl-2-propenyl acetate 
• 103-54-8 cinnamyl acetate 

Relevant academic research and scientific papers

Platinum-catalyzed direct amination of allylic alcohols under mild conditions: Ligand and microwave effects, substrate scope, and mechanistic study

Transition metal-catalyzed amination of allylic compounds via a π-allylmetal intermediate is a powerful and useful method for synthesizing allylamines. Direct catalytic substitution of allylic alcohols, which forms water as the sole coproduct, has recently attracted attention for its environmental and economical advantages. Here, we describe the development of a versatile direct catalytic amination of both aryl- and alkyl-substituted allylic alcohols with various amines using Pt-Xantphos and Pt-DPEphos catalyst systems, which allows for the selective synthesis of various monoallylamines, such as the biologically active compounds Naftifine and Flunarizine, in good to high yield without need for an activator. The choice of the ligand was crucial toward achieving high catalytic activity, and we demonstrated that not only the large bite-angle but also the linker oxygen atom of the Xantphos and DPEphos ligands was highly important. In addition, microwave heating dramatically affected the catalyst activity and considerably decreased the reaction time compared with conventional heating. Furthermore, several mechanistic investigations, including 1H and 31P{1H} NMR studies; isolation and characterization of several catalytic intermediates, Pt(xantphos)Cl2, Pt(η2-C3H5OH)(xantphos), etc; confirmation of the structure of [Pt(η3-allyl)(xantphos)]OTf by X-ray crystallographic analysis; and crossover experiments, suggested that formation of the π-allylplatinum complex through the elimination of water is an irreversible rate-determining step and that the other processes in the catalytic cycle are reversible, even at room temperature.

Allylic amination using well-defined [(NHC)Pd(?3-allyl)Cl] complexes and PPh3

The allylic amination reaction catalyzed by [(NHC)Pd(allyl)-Cl] complexes has been studied, and the presence of PPh3found to be essential for the catalytic system to be active. [(1-Mesityl-3-methylimidazol-2-ylidene)Pd(?3- C3H5)Cl] hasbeen used to optimize the conditions of the reaction with (E)-1,3-diphenylprop-3-enyl acetate and benzylamine under bi-phasic conditions (aqueous base/CH2Cl2). The best yields ofisolated product (98%) were obtained using aqueous 1 MK2CO3. The influence of the NHC ligand and the allyl frag-ment on the pre-catalyst was also examined. Two new neu-tral [(NHC)Pd(?3-1-RC3H4)Cl] complexes [NHC = 1-mesityl-3-methylimidazol-2-ylidene or 1-(2,6- diisopropylphenyl)-3-methylimidazol-2-ylidene; R = H or Ph] have been preparedand a decrease of the reaction time observed with the former. NMR studies have shown that this pre-catalyst is more easilyactivated than its ?3-allyl analogue and that the predominantactivation pathway involves attack of the amine at the allyl fragment. This reaction occurs exclusively in the presence ofPPh3, thus suggesting that cationic [(NHC)Pd(allyl)(PPh3)] +complexes, which are more electrophilic, are formed in situand allow the amine to react with the allyl fragment. A tetra-fluoroborate cationic complex has therefore been preparedfrom [(NHC)Pd(allyl)Cl], PPh3, and AgBF4 and fully charac-terized. This complex is an active pre-catalyst in the allylicamination reaction. The scope of the reaction was examinedunder the optimized reaction conditions with several dif-ferent nitrogen nucleophiles and allylic acetates. The amin-ation products were obtained in yields ranging from 73 to 98%, except for that from cyclohexenyl acetate and diben-zylamine. Finally, the reaction performed directly with theallylic alcohol and benzylamine led to a mixture of allylicamines in 9% yield. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009.