95581-63-8Relevant academic research and scientific papers
Hydrohalogenation reaction of substituted 1,2-allenic carboxylic acids, esters, amides, nitriles, and diphenyl phosphine oxides
Ma,Xie,Wang,Zhang,Shi
, p. 713 - 730 (2007/10/03)
The hydrohalogenation reaction of 1,2-allenic carboxylic acids, esters, amides, nitriles, and diphenyl phosphine oxides with HX or MX (X = I, Br, Cl, M = Na, Li) in different solvents, such as HOAc, CF3CO2H, and CF3CO
A study on the scope of the photochemical 1,3-migration of oximino groups in β,γ-unsaturated oximes and oxime derivatives
Armesto, Diego,Gallego, Mar G.,Horspool, William M.,Ramos, Ana
, p. 107 - 113 (2007/10/03)
While the aza-di-π-methane rearrangement is the normal photoreactive behaviour of β,γ-unsaturated imines and oxime acetates, the results obtained in this study show that 1,3-migrations of acetoxyimino groups in β,γ-unsaturated oxime acetates takes place only when all the parameters are correct. The rearrangement takes place when there is a quaternary carbon separating the two π-systems and when one of the radical centres in the intermediate cyclobutyl 1,4-biradical is stabilized by conjugation with a phenyl ring. Suppression of the free rotor effect also helps to promote the reaction. These criteria are fulfilled in compounds 1a and 7a. The reaction was extended to the β,γ-unsaturated oximes 1b and 7b where again the 1,3-migration of the oximino group took place. Copyright 1996 by the Royal Society of Chemistry.
Steric and Electronic Effects on the Photochemical Reactivity of Oxime Acetates of β,γ-Unsaturated Aldehydes
Armesto, Diego,Horspool, William M.,Gallego, Mar G.,Agarrabeitia, Antonia R.
, p. 163 - 170 (2007/10/02)
A general synthesis of 5-unsubstituted N-acetoxy 3,3-dimethyl-1-azapenta-1,4-dienes starting from 2-(1,3-dithian-2-yl)-2-methylpropanal is described.The influence of 5-phenyl, 4-phenyl, 5-cyclohexyl, 5-tert-butoxycarbonyl and 5,5-dicyclohexyl substitution on the outcome of the photochemical reactions of the oxime acetates of β,γ-unsaturated aldehydes has been studied with a view to proving or disproving the operation of a deactivating free rotor in the aza-di-?-methane rearrangement.The results obtained show that if the radical formed at C-5 can be stabilized by conjugation with an aryl group or by certain types of disubstitution then the aza-di-?-methane rearrangement takes place successfully.In any other situation the reaction fails.These results clearly show that the free rotor effect is not responsible for the failure of C-5 monosubstituted 1-aza-1,4-dienes to undergo the aza-di-?-methane rearrangement.
Unexpected Influence of Mono-phenyl Substitution on the Photochemistry of β,γ-Unsaturated Oxime Acetates
Armesto, Diego,Agarrabeitia, Antonia R.,Horspool, William M.,Gallego, Mar G.
, p. 934 - 936 (2007/10/02)
On irradiation of the oxime acetate of trans-2,2-dimethyl-4-phenylbut-3-enal (5) undergoes stereospecific aza-di-?-methane rearrangement to the oxime acetate of trans-2,2-dimethyl-3-phenylcyclopropanecarbaldehyde (7), while surprisingly the irradiation of the oxime acetate of 2,2-dimethyl-3-phenylbut-3-enal (10) follows a different reaction path and affords the oxime acetate of 4-methyl-3-phenylpent-3-enal (13) by a novel 1,3-migration pathway.
