Synthesis of Phosphoryl-Substituted Cyclopropanes Based on Cyano-Activated CH Acids. 1 : 2 Adduct-Product of O- and C-Alkylation of Dimedone

The reaction of (1,2-dibromo)(diphenyl)phosphine oxide with cyano-substituted CH acids (cyanoacetic acid ethyl ester and amide, benzyl cyanide) in the presence of sodium hydroxide in acetonitrile at a reagent ratio of 1 : 2 : 3 afforded phosphoryl-substituted cyclopropanes. It was shown that, in contrast to the indicated CH acids, the reaction of the phosphine oxide with dimedone led to the formation of a 1 : 2 adduct, the structure of which was established by the 1H, 31P, 13C NMR spectroscopy including DEPT, NOESY, HSQC, and HMBC techniques, as well as single crystal X-ray diffraction analysis method.