Synthesis and Structure of Phosphorylated Nitronorbornenes

Abstract

A procedure was suggested for preparing previously unknown phosphorylated nitronorbornenes from nitroethenephosphonates and cyclopentadienes. The structures of the products were studied by IR and 1H and 3 1P NMR spectroscopy. A single crystal X-ray diffraction study of bis(2-chloroethyl) 3-bromo-3-nitro- bicyclo[2.2.1]-5-heptene-2-phosphonate showed that the steric arrangement of the bicyclic fragment is typical of norbornenes. It is the endo-(NO2) diastereomer in which Br and P(O)(OC2H4Cl)2 substituents are eclipsed, and C2-C3 and C3-NO2 bonds are noticeably elongated.