The reactions of Wittig–Horner reagents with 1,3-dioxo-Δ2,α-indanmalononitrile

Wittig–Horner reagents ( 1a–e ) react with 1,3-dioxo-Δ^2,α-indanmalononitrile ( 2 ) to give the phosphonate adducts 3, 4, 5, 6, and 7 , respectively. Structural reasoning for the new products was based on compatible analytical and spectral data (IR, ¹H, ³¹P NMR, and MS). The mechanism that accounts for the formation of the new adducts is discussed. © 1997 John Wiley & Sons, Inc. Heteroatom Chem 8 : 253–257, 1997.