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Inter- and intramolecular cycloaddition reactions of ethenetricarboxylates with styrenes and α-halostyrenes have been investigated. The reactions of ethenetricarboxylates with styrenes or α-bromostyrenes in the presence of SnCl4 or SnBr4 stereoselectively gave 2,4-cis-substituted cyclobutanes. The intramolecular cycloaddition reactions of a series of styrene-functionalized ethenetricarboxylate amides, including in situ generated derivatives, showed high diversity of reaction modes depending on the structures and substituents of the substrates. The regioselectivity and stereoselectivity of the reactions as well as reaction mechanisms were discussed based on the DFT calculations.

Catalytic cyclization of allyl amides of ethenetricarboxylate leading to pyrrolidines has been examined. Reaction of allyl amides of ethenetricarboxylate with Sc(OTf) 3 (0.2 equiv) gave 4-hydroxymethyl-2-oxopyrrolidine derivatives as major products. The formation of hydroxymethylpyrrolidines may arise from participation of adventitious water in situ. Sc(OTf) 3 -catalyzed cyclization reactions of the allyl amides with TMSX (X = Cl, Br) proceeded efficiently to give halogenated 2-oxopyrrolidine derivatives. Sc(OTf) 3 -catalyzed cyclization reactions of the allyl ester with TMSX (X= Cl, Br) also proceeded to give halogenated 2-oxotetrahydrofuran derivatives.

The Lewis acid promoted reaction of 1,1-diarylallenes with ketone derivatives was examined. The tin(IV) chloride promoted reaction of diarylallenes with vinyl ketones gave indene derivatives through a conjugate addition/cyclization reaction. The reaction of diphenylallene with diethyl oxomalonate in the presence of one equivalent of tin(IV) chloride at –40 °C gave diethyl hydroxy(3-phenyl-1 H -inden-2-yl)malonate as the major product through a carbonyl addition/cyclization reaction, whereas the same reactants in the presence of 0.2 equivalents of tin(IV) chloride at 80 °C gave diethyl (3-phenyl-1 H -inden-2-yl)malonate. Diethyl hydroxy(3-phenyl-1 H -inden-2-yl)malonate was also converted into the latter product on heating at 80 °C in the presence of 0.2 equivalents of tin(IV) chloride.