The reactivity of various 2-oxyallyl cations toward 2, 2'-methylenedifuran (1b), 2, 2'- (hydroxymethyl) difuran (1c), 2, 2'-(trimethylsilylmethylene) difuran (1d), and di (2-furyl) methanone (1e) has been explored. Difuryl derivatives 1c, 1d, and 1e refused to undergo formal double [4+ 3]-cycloadditions. Conditions have been found to convert 1b into meso-1, 1'-methylenedi [(1 R, 1'S, 5 S, 5'R)-(3) and (±)-1, 1'-methylenedi [(1 RS, 1'SR, 5 SR, 5'RS)- ...