Les agrafes au silicium en synthèse organique

Doctorat en sciences chimiques -- UCL, 199

Diastéréosélectivité faciale des cycloadditions des azadiènes chiraux

Doctorat en sciences chimiques -- UCL, 199

Asymmetric Diels-alder Reactions With Chiral 1-azadienes

Chiral 1-azadienes 1 derived from alpha,beta-unsaturated aldehydes and Enders' hydrazines cycloadd to cyclic dienophiles with high facial selectivities. The adducts can be readily converted into enantiomerically pure piperidine derivatives

A Diels-alder Route Towards Pyrimidin-4-ones

N-acylimidates are readily silylated with t-butyldimethylsilyl triflate in the presence of triethylamine to give 2-aza-1,3-dienes. These react with activated nitriles to yield pyrimidin-4-ones

A highly efficient multicomponent synthesis of pyridones and pyrimidones by a [2+2+2] strategy

:The reaction of N-silylated iminoethers with 2-substituted acetyl chlorides yields activated 2-azadienes. These were shown to react with electron-deficient acetylenic dienophiles to yield pyridones. They also react with quinones to give the corresponding aromatized cycloadducts in good yields. The reaction of a-azadienes with activated nitriles provided a very practical route towards polysubstituted pyrimidones. A multicomponent protocol is reported which combines a N-t-butyldimethylsilyl iminoether, an acetyl chloride derivative and a dienophile in the presence of triethylamine without isolation of any intermediate. This provides an extremely practical and versatile route to various mono- and polycyclic azaaromatics with a predictable substitution pattern. Yields ranged from 43 % to 94 % for the complete sequence. (C) 1999 Elsevier Science Ltd. All rights reserved

A Diels-alder Route Towards Pyrimidin-4-ones

N-acylimidates are readily silylated with t-butyldimethylsilyl triflate in the presence of triethylamine to give 2-aza-1,3-dienes. These react with activated nitriles to yield pyrimidin-4-ones

Nouvelle m thode de synth(se des pyrimidones et pyridones

SIGLEBSE B226126F / UCL - Université Catholique de LouvainBEBelgiu