150151-36-3Relevant academic research and scientific papers
Ozonolysis of β-(Alkoxycarbonyl)- and β-Acyl-Substituted Vinyl Ethers. Cycloaddition Chemistry of the Derived α-Keto Ester O-Oxides and α-Diketone O-Oxides
Sugiyama, Tomohito,Yamakoshi, Hideyuki,Nojima, Masatomo
, p. 4211 - 4218 (2007/10/02)
Ozonolyses of a series of vinyl ethers 1a-h having electron-withdrawing substituent(s) at the β-position were carried out in methanol and also in aprotic solvents in the presence of 1,3-dipolarophiles.Methanol-trapping experiments revealed that the cleavage of the primary ozonides from vinyl ethers 1a,b,d-f is regioselective, providing in each case the corresponding α-keto ester O-oxides 3a,b and α-diketone O-oxides 3d-f.These electron-deficient carbonyl oxides 3a,b,d-f could undergo cycloadditions with a variety of 1,3-dipolarophiles, particularly nitrones, and give in each case the corresponding cycloadducts.
Synthesis and X-ray Analysis of Dihydro-1,2,4,5-trioxazine. Evidence of a Steowise Mechanism for the Cycloaddition of Carbonyl Oxides with Nitrones
Mori, Mitsuyuki,Sugiyama, Tomohito,Nojima, Masatomo,Kusabayashi, Shigekazu,McCullough, Kevin J.
, p. 2285 - 2294 (2007/10/02)
Carbonyl oxides, derived by ozonolysis of vinyl ethers, readily undergo cycloaddition reactions with nitrones affording dihydro-1,2,4,5-trioxazines in fair to excellent yield.The structures of dihydro-3,5,6-triphenyl-1,2,4,5-trioxazine (5f) and dihydro-3-cyclohexyl-5-methyl-6,6-diphenyl-1,2,4,5-trioxazine (5t) were unambiguously determined by X-ray analysis.Ozonolysis of 1-cyclohexyl-2-methoxyethene in the presence of either (E)- or (Z)-α-(4-methylphenyl)-α-phenyl-N-methylnitrone gave a 1:1 mixture of two stereoisomeric cycloadducts.This result, in conjunction with the structure of the relevant 5t, suggests that the cycloaddition proceeds by a stepwise mechanism.
