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The sulfuric acid catalyzed condensation of levulinic acid with glyoxylic acid at 80 °C, for 24 h under neat conditions gives 1-methyl-2,8-dioxabicyclo[3.3.0]oct-4-ene-3,7-dione in 92% yield. Catalytic reduction of this unsaturated bis-lactone provides a facile route to produce polyester monomer 1-methyl-2,8-dioxabicyclo[3.3.0]octane-3,7-dione from renewable feedstocks.

The ionic liquid promoted Skraup synthesis of quinolines involving the in situ formation of acrolein by dehydration of glycerol under microwave conditions.

N-Sulfinylarylamines react with 1,4-naphthoquinone to give 2-(N-arylsulfinamoyl)-1,4-naphthoquinones. The reaction is believed to occur via an initial 2 + 2 cycloaddition of the NS bond of the N-sulfinylamine with 1,4-naphthoquinone, followed by fragmentation of the 1,2-thiazetidine 1-oxide intermediate with a 1,3-H shift. N-Sulfinylarylamines add regiospecifically to 5-hydroxy-1,4-naphthoquinone to give 3-(N-arylsulfinamoyl)-5-hydroxy-1,4-naphthoquinones. 1,4-Benzoquinone reacts with three molecules of N-sulfinylarylamine to give adducts. Two molecules of N-sulfinylarylamine react with 1,4-benzoquinone as in the case of 1,4-naphthoquinone and the third molecule reacts at one of the CO groups of the benzoquinone with the elimination of a molecule of SO2. Hydrolysis of 2-(N-arylsulfinamoyl)-1,4-naphthoquinones with aqueous HCl gives 2-hydroxy-1,4-naphthoquinone.

N-Ethoxycarbonyl Dewar pyrrole 9, the first member of the parent ring, is formed via photofragmentation of 6 at –60 °C and trapped as its adduct with 1,3-diphenyl-isobenzofuran 11; above this temperature, 9 is unstable and isomerises to N-ethoxycarbonylpyrrole 10.

A new approach to the synthesis of cavity molecules is described in which the 1,3-dipolar ACE coupling method is used to join curved-frame spacer molecules with obtuse-angled alkenes. The curved-frame spacers are comprised of fused norbornenes in which each alternative bridge has the 7-methylene replaced by oxygen. Molecular modeling (AM1) has been used to evaluate the geometry of a selection of bis-crown ether systems, the largest of which has nine norbornane units in the frame, a separation of 20.7 A and the walls of the cavity having an interplanar angle of 36°.

Sensitised photo-oxidations of 8-hydroxy quinoline (l)or5-hydroxy quinoline (2) gives quinoline-5,8-quinone (3) in 64-70% yield.

Nitrosation of bis arylidene acetone oximes with nitrous acid in glacial acetic acid gives 3-vinyl pyrazolone-N,N′-dioxides in 32–37% yield. Similar reactions of 2-arylidene-6-(hydroxylamino-aryl-methyl)-cyclohexanone oximes give tricyclic compounds with dioxa-2,6-diaza-spiro[4,4]nona-2,8-diene ring systems in 77–84% yield.

The aldehydes (I) react with hydrazoic acid (II) and methanol (III) to give the α-azido ethers (IV).