A new generation of porous polymer networks has been obtained in quantitative yield by reacting two rigid trifunctional aromatic monomers (1,3,5-triphenylbenzene and triptycene) with two ketones having electron-withdrawing groups (trifluoroacetophenone and isatin) in superacidic media. The resulting amorphous networks are microporous materials, with moderate Brunauer-Emmett-Teller surface areas (from 580 to 790 m g), and have high thermal stability. In particular, isatin yields networks with a very high narrow microporosity contribution, 82% for triptycene and 64% for 1,3,5-triphenylbenzene. The existence of favorable interactions between lactams and CO molecules has been stated. The materials show excellent CO uptakes (up to 207 mg g at 0 °C/1 bar) and can be regenerated by vacuum, without heating. Under postcombustion conditions, their CO/N selectivities are comparable to those of other organic porous networks. Because of the easily scalable synthetic method and their favorable characteristics, these materials are very promising as industrial adsorbents.

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The identification of some intermediates of the reactions between β-aminoenones and malononitrile to give 2(1H)-pyridinones has allowed us to obtain valuable information concerning its mechanism. These reactions begin with a conjugated addition of the nitrile to the enone followed by elimination. The compounds thus obtained cyclize to nonisolable 2H-pyran-2-imine. This afforded 2(1H)pyridinones by ring opening to unsaturated aminoamides followed by cyclization (Dimroth-type rearrangement).

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4-Chlorocoumarin has been shown to be a highly versatile starting material when treated with organometallic reagents. Thus, it has allowed the selective synthesis either directly, or through simple additional transformations, of 4-alkylcoumarins (with R,CuLi in Et,O, or Pr'Mg Br in TH F), 2-chloro-2-(0-hydroxyphenyl)allyl alcohols or their 4-chloro-2H-1 -benzopyran derivatives (with RMgX in TH F), 2-(o-hydroxyphenyl)prop-2-ynyt alcohols (when non-acid hydrolysis were used in the latter reactions) and 2,2,4-trialky1-2H-l -benzopyrans (when excess of RMgX or R,AI reagents were used).