41108-92-3

Upstream product

• 122-78-1 phenylacetaldehyde 
• 123-54-6 acetylacetone 
• 41002-50-0 4-acetoxy-3-penten-2-one 
• 119448-13-4 ethyl β-styrylcarbonate 
• 10521-96-7 styryl acetate 

Downstream Products

• 42762-56-1 (E)-5-phenylpent-4-en-2-one 
• 134418-83-0 (E)-3-diazo-5-phenylpent-4-en-2-one 
• 17357-78-7 1-(5-phenyl-1H-pyrazol-3-yl)ethan-1-one 
• 877-94-1 phenyl-5 pentene-4 one-2 

Relevant academic research and scientific papers

Synthesis of Allylboranes via Cu(I)-Catalyzed B-H Insertion of Vinyldiazoacetates into Phosphine-Borane Adducts

Cu(I) catalysts enable C-B bond formation via direct insertion of vinyldiazoacetates into B-H bonds of borane-phosphine Lewis adducts to form phosphine-protected allylboranes under mild conditions. The resulting allylborane-phosphine Lewis adducts can be used in the diastereoselective allylation of aldehydes directly without the need for removal of the phosphine. The allylation reaction proceeds with high diastereoselectivity and yields 5,6-disubstituted dihydropyranones after treatment with an appropriate acid.

Intramolecular Cyclization of Vinyldiazoacetates as a Versatile Route to Substituted Pyrazoles

Vinyldiazo compounds undergo a thermal electrocyclization to form pyrazoles in yields of up to 95percent. The reactions are operationally simple, use readily available starting materials, require no intervention of a catalyst, and enable the synthesis of mono-, di- A nd tri-substituted pyrazoles. With the ability to produce highly substituted pyrazoles and the flexibility in installing various types of substituents, this method constitutes a new entry to this valuable heterocyclic scaffold and may be of interest to all branches of the chemical industry.

Enzyme Promiscuity as a Remedy for the Common Problems with Knoevenagel Condensation

A new protocol based on lipase-catalyzed tandem reaction toward α,β-enones/enoesters is presented. For the synthesis of the desired products the tandem process based on enzyme-catalyzed hydrolysis and Knoevenagel reaction starting from enol acetates and aldehyde is developed. The relevant impact of the reaction conditions including organic solvent, enzyme type, and temperature on the course of the reaction was revealed. It was shown that controllable release of the active methylene compound from the corresponding enol carboxylate ensured by enzymatic reaction diminishes significantly the formation of the unwanted co-products. Furthermore, this protocol was extended by including a second tandem chemoenzymatic transformation engaging various aldehyde precursors. After a careful optimization of the reaction conditions, the target products were obtained with yields up to 86 % and with excellent E/Z-selectivity.

Corrigendum to: Enzyme Promiscuity as a Remedy for the Common Problems with Knoevenagel Condensation (Chemistry – A European Journal, (2019), 25, 43, (10156-10164), 10.1002/chem.201901491)

In the published paper, there is a mistake in the labelling of compounds in Figure. A corrected version of that Figure appears below. The authors apologise for the mistake. Figure (Figure presented.) Unsaturated 2,4-pentanediones obtained by enzyme-catalyzed tandem Knoevenagel reaction. Reaction conditions: aldehyde (1 mmol), 4-acetoxy-3-penten-2-one (5 a, R1=R2=R3=Me) (3 mmol), and PPL (100 mg) in tert-butyl alcohol/ 5 % H2O v/v (2 mL) for 72 h at 20 °C, 200 rpm. [a] With vinyl acetate. [b] With ethyl β-styrylcarbonate. [c] With styryl acetate.

One-pot, three-component approach to the synthesis of 3,4,5-trisubstituted pyrazoles

An operationally simple and high yielding protocol for the synthesis of polyfunctional pyrazoles has been developed through one-pot, three-component coupling of aldehydes, 1,3-dicarbonyls, and diazo compounds as well as tosyl hydrazones. The reaction proceeds through a tandem Knoevenagel condensation, 1,3-dipolar cycloaddition, and transition metal-free oxidative aromatization reaction sequence utilizing molecular oxygen as a green oxidant. The scope of the reaction was studied by varying the aldehyde, 1,3-dicarbonyl, and diazo component individually.