CHEMISTRY OF PHOSPHORUS YLIDES 101REACTION WITH PHOSPHACUMULENES IV. SYNTHESIS OF PYRAN, PHOSPHORANYLIDENE, OXAPHOSPHORIN AND OXAZAPHOSPHORIN FROM THE REACTION OF 1,3-DIOXO-Δ2,α-INDANMALONONITRILE WITH PHOSPHORANES AND IMINOPHOSPHORANES

Abstract

Abstract 1,3-Dioxo-Δ2,α-indanmalononitrile (1) reacts with the active ketenylidene-(2a) and thioketenylidenetriphenyl phosphorane (2b) to give the corresponding pyrans 3 (X[dbnd]O or S). The reaction of pyran 3 with p-nitrobenzaldehyde proceeds according to the Wittig reaction to give the respective ethylenes 4a, b. On the other hand, phosphoranylidenes 7a-e were isolated from the reaction of stable phosphoranes 5a-e with the dioxoindanmalononitrile 1. Moreover, the oxaphosphorin 9 and oxazaphosphorin 11, were prepared from the reaction of compound 1, with the phosphorane 8, and the iminophosphorane 10, respectively. Structures of the new compounds were assigned according to consistent analytical and spectroscopic measurements.