Mechanism of Oxygen Transfer in the Epoxidation of an Olefin by Molecular Oxygen in the Presence of an Aldehyde

Abstract

[reaction: see text] The reaction pathway for peroxide-initiated aldehyde-mediated oxidation of olefins to epoxides by molecular oxygen has been studied. The pathways of reaction via a peroxy acid or an acyl peroxy radical have been differentiated by investigation of the reaction of 4 with oxygen to provide 6 via 8.

Indium-catalyzed coupling reaction between silyl enolates and alkyl chlorides or alkyl ethers

“…23. Products 3ad, 37 3ah, 38 5ba, 39 5ac, 40 5ab, 41 5aa, 42 12, 43 16, 44 and 25 45 were in an excellent agreement with the reported data. Compound 24aa is the same product as 3aa.…”

Intramolecular Cyclization of 3,3‐Diarylpropenylamides of Electron‐Deficient Alkenes: Stereoselective Synthesis of Functionalized Hexahydrobenzo[f]isoindoles

“…( Z )‐Cinnamyl bromide was prepared by reaction of ( Z )‐cinnamyl alcohol with PBr 3 and pyridine in ether and used without further purification. Z ‐Cinnamylamines 2a–b were prepared by reaction of benzylamine or cyclohexylamine (2 equiv.)…”

“…(Z)-Cinnamyl bromide [32] was prepared by reaction of (Z)-cinnamyl alcohol with PBr 3 and pyridine in ether and used without further purification. Z-Cinnamylamines 2a-b were prepared by reaction of (Z)-Benzyl Cinnamylamine (2a): Z/E = 5:1 (2.4 mmol scale, 274 mg, 51 %); R f = 0.1 (hexane/diethyl ether = 1:1); colorless oil.…”

Mechanism of Propylene Epoxidation via O2 with Co‐Oxidation of Aldehydes by Metalloporphyrins

“…The rest paths are the free radical reaction (Figure 6a, Figure 6c and Figure 6d), it seems to be the free radical addition of propylene to generate intermediates. [36][37][38][39][40] After the formation of peroxyacyl radical, the chain terminal oxygen attacks the double bond carbon, when the attacked site is C1 the free energy barrier is 40.5 kJ mol -1 with generation of IM1 ( Figure 5, E), otherwise is 46.5 kJ mol -1 to obtain IM2 (Figure 5, F).…”