554446-82-1

Upstream product

• 124-13-0 Octanal 
• 613-94-5 benzoic acid hydrazide 

Downstream Products

• 1163303-35-2 2-heptyl-5-phenyl-[1,3,4]oxadiazole 
• 1366284-41-4 N-(2,2-difluoro-1-oxo-1-phenyldecan-3-yl)benzohydrazide 

Relevant academic research and scientific papers

Mechanism and selectivity of N -triflylphosphoramide catalyzed (3+ + 2) Cycloaddition between hydrazones and alkenes

Bronsted acid catalyzed (3+ + 2) cycloadditions between hydrazones and alkenes provide a general approach to pyrazolidines. The acidity of the Bronsted acid is crucial for the catalytic efficiency: the less acidic phosphoric acids are ineffective, while highly acidic chiral N-triflylphosphoramides are very efficient and can promote highly enantioselective cycloadditions. The mechanism and origins of catalytic efficiencies and selectivities of these reactions have been explored with density functional theory (M06-2X) calculations. Protonation of hydrazones by N-triflylphosphoramide produces hydrazonium-phosphoramide anion complexes. These ion-pair complexes are very reactive in (3+ + 2) cycloadditions with alkenes, producing pyrazolidine products. Alternative 1,3-dipolar (3 + 2) cycloadditions with the analogous azomethine imines are much less favorable due to the endergonic isomerization of hydrazone to azomethine imine. With N-triflylphosphoramide catalyst, only a small distortion of the ion-pair complex is required to achieve its geometry in the (3+ + 2) cycloaddition transition state. In contrast, the weak phosphoric acid does not protonate the hydrazone, and only a hydrogen-bonded complex is formed. Larger distortion energy is required for the hydrogen-bonded complex to achieve the ion-pair geometry in the cycloaddition transition state, and a significant barrier is found. On the basis of this mechanism, we have explained the origins of enantioselectivities when a chiral N-triflylphosphoramide catalyst is employed. We also report the experimental studies that extend the substrate scope of alkenes to ethyl vinyl ethers and thioethers.

Efficient oxidative cyclization of N -acylhydrazones for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles using t-BuOI under neutral conditions

An efficient procedure for the oxidative cyclization of N -acylhydrazones was developed utilizing tert-butyl hypoiodite (t-BuOI), which is generated in situ from t -BuOCl and NaI. A variety of 2,5-disubstituted 1,3,4-oxadiazoles were synthesized in high yields within short reaction time. The method is also suitable for cyclization of N -acylhydrazones derived from heterocyclic aldehydes and aliphatic aldehydes. Mild reaction conditions and simple workup operations make the procedure a good alternative for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles.

Indium-mediated catalytic enantioselective allylation of N -benzoylhydrazones using a protonated chiral amine

A catalytic enantioselective indium-mediated allylation of N-benzoylhydrazones in conjunction with a protonated chiral amine affording enantioenriched homoallylic amines with an extremely high level of enantioselectivity and chemical yield was developed.

Highly enantioselective radical addition to N-benzoyl hydrazones using chiral ammonium salts

In the presence of a protonated cinchonine derivative, radical addition reactions proceeded efficiently, affording addition adducts in high yields with an extremely high enantioselectivity. The chiral ammonium salt was recyclable after a simple aqueous workup. The reaction provides environmentally benign reaction conditions. Copyright