71403-94-6Relevant articles and documents
Selective epoxidation of olefins by vanadylporphyrin [V IV O(TPP)] and electron deficient nonplanar β-octabromovanadylporphyrin [V IV O(TPPBr8)]
Maurya, Mannar R.,Prakash, Ved,Sankar, Muniappan
, (2021/12/31)
Meso-tetraphenylporphyrinatooxidovanadium(IV) [VIVO(TPP)] (1) and 2,3,7,8,12,13, 17,18-octabromo-meso-tetraphenylporphyrinatooxidovanadium(IV) [VIVO(TPPBr8)] (2) were synthesized and characterized by various spectroscopic techniques. 1 and 2 were utilized
Characteristics and hazards of the cinnamaldehyde oxidation process
Dai, Su-Yi,Lai, Fang,Li, Wei-Guang,Li, Yuan-Lin,Liang, Min,Liu, Xiong-Min,Ma, Li,Yu, Chang
, p. 19124 - 19133 (2020/06/08)
Pressure and temperature behavior of the cinnamaldehyde oxidation process was determined using a custom-designed mini closed pressure vessel test (MCPVT), which is a new method to investigate the stability and hazard assesment of the cinnamaldehyde oxidation reaction. The oxidation products were analyzed by gas chromatography-mass spectrometry (GC-MS). The results showed that cinnamaldehyde was stable under nitrogen atmosphere but very unstable under oxygen atmosphere. The initial oxidation products were analyzed by iodimetry and the cinnamaldehyde peroxide value could reach 139.44 mmol kg?1when the oxidation temperature was 308 K. The oxidation kinetics of cinnamaldehyde were studied by using the pressureversustime (P-t) curves obtained from the MCPVT process. The reaction is a second-order reaction, the kinetic equation is ln k= ?2233.66 × (1/T) + 11.19, and the activation energyEais 18.57 kJ mol?1at 308-338 K. The explosion of the cinnamaldehyde oxidation reaction was observed by MCPVT, in which the onset temperature was 373 K. The main products of cinnamaldehyde oxidation are acetaldehyde, benzaldehyde, phenylacetaldehyde, acetophenone, 2-hydroxyphenyl acetone, cinnamaldehyde epoxide, benzoic acid, and cinnamic acid. Oxidation is a three-step process: (1) cinnamaldehyde reacts with oxygen to form peroxides; (2) complex oxidation reactions are caused by the thermal decomposition of peroxides; (3) rapid oxidation and thermal decomposition lead to explosion hazard.
Borylation and rearrangement of alkynyloxiranes: A stereospecific route to substituted α-enynes
Fuentespina, Ruben Pomar,De La Cruz, José Angel Garcia,Durin, Gabriel,Mamane, Victor,Weibel, Jean-Marc,Pale, Patrick
supporting information, p. 1416 - 1424 (2019/07/10)
1,3-Enynes are important building blocks in organic synthesis and also constitute the key motif in various bioactive natural products and functional materials. However, synthetic approaches to stereodefined substituted 1,3-enynes remain a challenge, as they are limited to Wittig and cross-coupling reactions. Herein, stereodefined 1,3-enynes, including tetrasubstituted ones, were straightforwardly synthesized from cis or trans-alkynylated oxiranes in good to excellent yields by a one-pot cascade process. The procedure relies on oxirane deprotonation, borylation and a stereospecific rearrangement of the so-formed alkynyloxiranyl borates. This stereospecific process overall transfers the cis or trans-stereochemistry of the starting alkynyloxiranes to the resulting 1,3-enynes.