A combined experimental and theoretical study of the polar [3+2] cycloaddition of electrophilically activated carbonyl ylides with aldehydes and imines

Ghenia Bentabed-Ababsa (1, 2) , Aicha Derdour (2) , Thierry Roisnel (3) , José A. Saez (4) , Patricia Pérez (5) , Edouardo Chamorro (5) , Luis .R. Domingo (4) , Florence Mongin (3)

1 CPM - Chimie et Photonique Moléculaires
2 Laboratoire de Synthèse Organique Appliquée
3 ISCR - Institut des Sciences Chimiques de Rennes
4 UV - Universitat de València
5 UNAB - Universidad Andrés Bello [Santiago]

Numerous 2,5-diaryl-1,3-dioxolane-4,4-dicarbonitriles and 2,4-diphenyl-1,3-oxazolidine-5,5- dicarbonitriles have been synthesized by [3+2] cycloaddition reactions between carbonyl ylides generated from epoxides, and aldehydes or imines. In contrast to the use of aldehydes (3,4,5- trimethoxybenzaldehyde, piperonal, 1-naphthaldehyde, indole-3-carboxaldehyde, furan-2- carboxaldehyde and thiophene-2-carboxaldehyde), the reactions performed with imines (N- (phenylmethylene)methanamine, N-(1,3-benzodioxol-5-ylmethylene)propylamine, N-(1,3-benzodioxol- 5-ylmethylene)butylamine and N-(1,3-benzodioxol-5-ylmethylene)benzylamine) proceed diastereoselectively. The effect of microwave irradiation on the outcome of the reaction was studied. The mechanism of these [3+2] cycloaddition reactions has been theoretically investigated using DFT methods. These cycloadditions, which have one-step mechanisms, consist of the nucleophilic attack of the aldehyde oxygen or imine nitrogen on the carbonyl ylide. For the reaction with aldehydes, a back donation effect is responsible for the unexpected reverse charge transfer found at the transition structure. The analysis of the reactivity indices indicates that the large electrophilic character of the carbonyl ylides induces them to act as strong electrophiles in these polar [3+2] cycloaddition reactions.

Domaines: Chimie organique

Ghenia Bentabed-Ababsa, Aicha Derdour, Thierry Roisnel, José A. Saez, Patricia Pérez, et al.. A combined experimental and theoretical study of the polar [3+2] cycloaddition of electrophilically activated carbonyl ylides with aldehydes and imines. Journal of Organic Chemistry, 2009, 74 (5), pp.2120-2133. ⟨10.1021/jo8027104⟩. ⟨hal-00784590⟩