Giampiero Spalluto

Tandem michael reactions for the construction of pyrrolidine and piperidine ring systems

Abstract A convergent one-pot construction of disubstituted pyrrolidine and piperidine frameworks has been accomplished through a simple protocol involving intermolecular conjugate addition of a nitrogen nucleophile to an electrophilic olefin followed by intramolecular trapping of the generated enolate by a built-in α,β,-unsaturated acceptor.

Enantioselective synthesis of (+)- and (−)-α-allokainic acid

Abstract A concise enantioselective route to (+)- and (−)-a-allokainic acid from D- and L-serine respectively has been established by enantio- and diastereo-selective tandem Michael reaction methodology for the construction of three chiral centers in a single stage.

Generation and cycloaddition reactions of 3-substituted-2-nitro-1,3-dienes

Abstract Two procedures for the regiospecific preparation of 3-substituted-2-nitro-1,3-dienes have been developed. The cycloaddition chemistry of the in situ generated dienes has been investigated.

4-Isopropyl-2-oxazolin-5-one anion as a new convenient formyl anion equivalent for conjugate addition and aldol reactions.

Abstract The anion of the title compound, simply generated in the presence of catalytic amount of triethylamine, acts as nucleophilic acylating equivalent of formaldehyde reacting with both common electrophilic olefins or aldehydes to give moderate to good yield of Michael or aldol adducts respectively, which are easily hydrolized by dilute acid at ambient to temperature to afford the corresponding aldehydes.

A new enantioselective route to kainoids: application to the formal synthesis of (–)-α-kainic acid

The enantioselective synthesis of a 2,3,4-trisubstituted pyrrolidine featuring the kainoid C-2, C-3 trans, C-3, C-4 cis arrangement of substituents has been accomplished through a tandem Michael reaction strategy involving 2-nitro-3-methylbuta-1,3-diene as electrophilic alkene, the removable electron-withdrawing group acting as a template for control of the stereochemistry of the cyclization, together with a secondary benzylamine incorporating a chiral centre at the carbon bearing the nitrogen nucleophile and an appropriate α,β-unsaturated acceptor able to trap the initially formed nitronate.