Realizing an Aza Paternò–Büchi Reaction

Intramolecular atropselective aza Paternò–Büchi reaction involving atropisomeric enamide and imine functionalities under sensitized irradiation leads to azetidine products in good yield and selectivity (ee >96 %). A mechanistic model based on detailed photophysical and isomerization kinetic studies is provided that shed light into the reactivity of enamides leading to aza Paternò–Büchi reaction.     

A stereodivergent route to epimeric 2-piperidinylglycines: application to the synthesis of carbocyclic β-lactam derivatives

A route to two epimeric hitherto unknown 2-piperidinylglycine derivatives, as precursors of carbocyclic β-lactam derivatives, has been developed, which features diastereoselective addition of allyl metal reagents to an N-allylimine derivative of Garner’s aldehyde and ring-closing metathesis as key steps.     

α-Phenylselanyl imines: preparation of β-phenylselanyl amines and original synthesis of allylaziridines

Resorting to suitable methods, a wide variety of α-phenylselanyl imines 2-5 were prepared from α-phenylselanyl aldehydes and α-phenylselanyl ketones 1. These compounds were reduced to afford β-phenylselanyl amines 6-9. Our experimental conditions have limited the well known deselenenylation side-reaction occurring with most hydrides. On the other hand, the reaction of α-phenylselanyl imines 2 with organometallics led to the expected addition products only in the case of allylated derivatives. Depending on the temperature, either β-phenylselanyl amines 11 or unexpected allylaziridines 12 were recovered.     

An unexpected base-induced rearrangement of tritylamine

An unexpected rearrangement was observed during the treatment of tritylamine with n-butyllithium, leading to the formation of an imine.     

Practical synthesis of 3-bromo-5,6-dihydropyridin-2-ones via β,γ-unsaturated α-bromo-ketene/imine cycloaddition

An approach to 3-bromo-4-alkyl-6-aryl-5,6-dihydropyridin-2-ones and 3-bromo-5-ethyl-6-aryl-5,6-dihydropyridin-2-ones starting from β,γ-unsaturated α-bromoketenes and imines is reported. The presence of a bromine atom on the double bond allows performing aziridination or bromine displacement with an amine. The reaction gave fused bicyclic N-allyl-aziridines or 3-amino-substituted 5,6-dihydropyridin-2-ones, depending on the substituents on the six-membered ring.     

Examples of interesting non-metal compounds derived from elemental fluorine

Elemental fluorine is essential for the preparation of many fluorine-containing compounds. A few examples from the author's past research are presented to illustrate this in tribute to the Centenary of the awarding of the Nobel Prize to Henri Moissan.