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2-Aminomethyl-1,3-butadienes and 2,3-bis(aminomethyl)-1,3-butadienes, readily prepared by the Grignard cross-coupling reaction of 2-bromo-2-aminopropene and vinylic bromides, are good Diels–Alder dienes toward various activated dienophiles to afford aminomethyl-substituted cyclohexenes.

2-Trimethylsilylethyl-1,3-butadiene, readily prepared by the cross-coupling reaction of the Grignard reagent of 3-bromo-3-butenyltrimethylsilane with vinyl bromide catalyzed by a nickel-phosphine complex, works as a synthetic equivalent to 3-methylene-1,4-pentadiene (parent [3]dendralene) by the consecutive Diels-Alder reactions.

A novel preparation of 1,3-oxathiane derivatives through Pummerer rearrangement of γ, δ-unsaturated sulfinyl compounds and its plausible mechanism are described.

Reactions of 1,3-disubstituted 5-aminopyrazole-4-carbonitrile derivatives ( 3a-o ) with dimethyl acetylenedicarboxylate in the presence of potassium carbonate in dimethyl sulfoxide gave the corresponding dimethyl 1,3-disubstituted pyrazolo[3,4-b]pyridine-5,6-dicarboxylates ( 4a-o ) which were allowed to react with excess hydrazine hydrate in ethanol under reflux followed by heating at 250–300 °C to give 1,3-disubstituted 4-amino-1H-pyrazolol [4′,3′:5,6]pyrido[2,3-d]pyridazine-5,8(6H,7H)-diones ( 7a-s ) in good yields. These tricyclic pyridazine derivatives were evaluated for chemiluminescence. Some were found to be more efficient than luminol in light production. 4-Amino-3-methylsufonyl-1-phenyl-1H-pyrazolo [4′,3′:5,6]pyndo[2,3-d]pyridazine-5,8(6H,7H)-dione( 7r ) showed the greatest chemiluminescence intensity derivatives in the presence of H 2 O 2 , peroxidase, in a solution of phosphate buffer pH 8.0

Several γ, δ-unsaturated sulfinyl compounds were prepared and their reactions with p-toluenesulfonic acid were examined. Conformationally rigid γ, δ-unsaturated sulfinyl compounds such as endo-(alkylsulfinyl)norbornene or 1-(alkylsulfinyl)-2-isopropenylbenzene derivatives afforded 1, 3-oxathianes through intramolecular Pummerer rearrangement.

The preparation of β-hydroxylignans intermediates via Baylis-Hillman reaction isdes cribed.