866562-23-4

Upstream product

• 100-52-7 benzaldehyde 
• 1066-54-2 trimethylsilylacetylene 
• 108-24-7 acetic anhydride 
• 89530-34-7 1-phenyl-3-trimethylsilylprop-2-yn-1-ol 

Downstream Products

• 31683-47-3 1-(trimethylsilyl)-3-phenylprop-1-yne 
• 16169-88-3 1-phenylprop-2-ynyl acetate 
• 13712-55-5 2,5-Dimethyl-1,3-diphenylpyrrole 
• 94964-57-5 2-methyl-1,3-diphenyl-4,5,6,7-tetrahydro-1H-indole 

Relevant academic research and scientific papers

Synthesis of multi-substituted allenes from organoalane reagents and propargyl esters by using a nickel catalyst

A highly efficient and simple route for the synthesis of multi-substituted allenes has been developed by a nickel catalyzed SN2′ substitution reaction of propargyl esters with organic aluminium reagents under mild conditions, which gave the corresponding multi-substituted allenes in good to excellent yields (up to 92%) and high selectivities (up to 99%) at 60 °C for 6 h in THF. Aryls bearing electron-donating or electron-withdrawing groups in propargyl esters gave products in good yields. In addition, the multi-substituted allenes bearing a thienyl or a pyridyl group were obtained in 95-97% selectivities with isolated yields of 72-83%. Furthermore, the SN2′ substitution reaction worked efficiently with propargyl carbonate compounds as well. On the basis of the experimental results, a possible catalytic cycle has been proposed.

Synthesis of Multisubstituted Allenes via Palladium-Catalyzed Cross-Coupling Reaction of Propargyl Acetates with an Organoaluminum Reagent

We describe a convenient method for the synthesis of multisubstituted allenes from cross-coupling of propargyl acetates with -organoaluminum reagent: The reaction of propargyl acetates with 1.2 equivalents of organoaluminum reagent mediated by Pd(PPh3)2Cl2 (1 mol%)/Ph3P (2 mol%) and K2CO3 in THF may produce tri- or tetrasubstituted allenes in good to excellent yields (83-94%) and high regio-selectivities (up to 99%) at 60 °C in 3-4 hours.

Highly Efficient Synthesis of Multi-Substituted Allenes from Propargyl Acetates and Organoaluminum Reagents Mediated by Palladium

A simple and mild catalytic S N 2′ substitution reaction of propargyl acetates with organoaluminum reagents is reported. The S N 2′ substitution reaction of propargyl acetates with organoaluminum reagents mediated by Pd(PhP 3) 2 Cl 2 (1 mol%)/PPh 3 (2 mol%)/K 2 CO 3 in tetrahydrofuran at 60 °C for 3-4 hours afforded the corresponding multi-substituted allenes in good yields (up to 94%) with high selectivities (up to 99%). The process was simple and easily performed, which offers an efficient method to synthesize the multi-substituted allene derivatives.

Highly efficient synthesis of allenes from trimethylaluminum reagent and propargyl acetates mediated by a palladium catalyst

A series of propargyl acetates were prepared and used as propargyl electrophiles for coupling reactions with trimethylaluminum. The simple catalytic system of palladium(II) acetate (1 mol-%) and tri(o-tolyl)phosphine (2 mol-%) worked efficiently for a wide variety of aromatic and aliphatic propargyl acetates, producing the substituted allenes in good to excellent yields of up to 94% in tetrahydrofuran. The process was simple and easily performed, and it provides an efficient method for the synthesis of substituted allene derivatives. On the basis of the experimental results, a possible catalytic cycle has been proposed.

Gold-catalyzed regioselective hydration of propargyl acetates assisted by a neighboring carbonyl group: Access to α-acyloxy methyl ketones and synthesis of (±)-actinopolymorphol B

A general atom-economical approach for the synthesis of α-acyloxy methyl ketone is demonstrated through regioselective hydration of a wide range of propargyl acetates. Readily available catalyst comprising of 1% Ph 3PAuCl and 1% AgSbF6 in dioxane-H2O efficiently hydrolyzes the terminal alkynes of the propargyl acetate in the absence of acid promoters at ambient temperature within a short time. Effective regioselective hydration is facilitated by the neighboring carbonyl group as demonstrated through 18O-labeling study. Compatibility of functional moieties and tolerance to various acid-labile protecting groups are observed. The catalytic condition is also suitable to perform hydration of TMS-substituted propargyl acetates, even though it requires prolonged reaction time for completion. Stereointegrity of the propargylic acetate is preserved during the hydration. The robustness of the system is successfully demonstrated through gram scale preparation of the product in nearly quantitative yield. The common α-acyloxy methyl ketone is transformed to 1,2-diol and 1,2-amino alcohol derivatives. Synthesis of actinopolymorphol B is achieved for the first time involving hydration of the propargyl acetate as the key step.

[(NHC)AuI]-catalyzed formation of conjugated enones and enals: An experimental and computational study

The [(NHC)AuI]-catalyzed (NHC = N-heterocyclic carbene) formation of α,β-unsaturated carbonyl compounds (enones and enals) from propargylic acetates is described. The reactions occur at 60°C in 8 h in the presence of an equimolar mixture of [(NHC)AuCl] and AgSbF6 and produce conjugated enones and enals in high yields. Optimization studies revealed that the reaction is sensitive to the solvent, the NHC, and, to a lesser extent, to the silver salt employed, leading to the use of [(ItBu)AuCl]/ AgSbF6 in THF as an efficient catalytic system. This transformation proved to have a broad scope, enabling the stereoselective formation of (E)-enones and -enals with great structural diversity. The effect of substitution at the propargylic and acetylenic positions has been investigated, as well as the effect of aryl substitution on the formation of cinnamyl ketones. The presence or absence of water in the reaction mixture was found to be crucial. From the same phenylpropargyl acetates, anhydrous conditions led to the formation of indene compounds via a tandem [3,3] sigmatropic rearrangement/intramolecular hydroarylation process, whereas simply adding water to the reaction mixture produced enone derivatives cleanly. Several mechanistic hypotheses, including the hydrolysis of an allenol ester intermediate and SN2′ addition of water, were examined to gain an insight into this transformation. Mechanistic investigations and computational studies support [(NHC)AuOH], produced in situ from [(NHC)AuSbF6] and H 2O, instead of cationic [(NHC)AuSbF6] as the catalytically active species. Based on DFT calculations performed at the B3LYP level of theory, a full catalytic cycle featuring an unprecedented transfer of the OH moiety bound to the gold center to the C≡C bond leading to the formation of a gold-allenolate is proposed.