Delso, Ignacio; Marca, Eduardo; Mannucci, Vanni; Tejero, Tomas; Goti, Andrea; Merino, Pedro published the artcile< Tunable Diastereoselection of Biased Rigid Systems by Lewis Acid Induced Conformational Effects: A Rationalization of the Vinylation of Cyclic Nitrones En Route to Polyhydroxylated Pyrrolidines>, Application In Synthesis of 617-55-0, the main research area is tunable diastereoselective vinylation cyclic nitrone Lewis acid conformational effect; pyrrolidine polyhydroxylated diastereoselective preparation.
The diastereofacial selection in addition reactions to biased rigid systems can be modulated by the action of Lewis acids. As an example, the stereoselectivity of the nucleophilic addition of vinylmagnesium bromide (VMB) to cyclic nitrones in the presence of diethylaluminum chloride (DEAC) shows a strong dependence on the temperature and the carbon substituent adjacent at the reaction center; it is remarkable that whereas a high selectivity is obtained at higher temperatures, in the presence of DEAC, a trend to invert the stereochem. course of the reaction is observed at lower temperatures, provided the substituent at C3 of the pyrrolidine ring allows delivery of the vinyl moiety. This behavior and difference in selectivity is to be attributed to the high conformational barriers of the intermediate nitrone-DEAC-VMB complex. A clear inversion of the selectivity is observed at -78 °C for the reaction of the nitrone protected as an O-Me derivative The present study provides a rationalization for the stereocontrolled addition of nucleophiles to rigid systems (cyclic nitrones).
Chemistry – A European Journal published new progress about Conformational barrier (of nitrone-Grignard-Al complex). 617-55-0 belongs to class esters-buliding-blocks, and the molecular formula is C6H10O5, Application In Synthesis of 617-55-0.
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics