5544
J. Org. Chem. 1991,56,5544-5553
1265,1098,961 cm-'. Anal. Calcd for CUHaaOlo: C, 61.27,H, 4.72. Found C, 61.59; H, 4.65. Tetramethyl 1,1,S,S-Tetracyano-l,la,2,3,Sa,5,6,7-octah y c l r o - a ~ h y l p ~ ~ t ~ e 2 ~ , 6 , ~ t . e(13, t~~ m-DIB and DDED). Cycloaddition run in acetonitrile for 3 days. Adventitious polymerization occurred, leading to very low yield (