Reactions of phosphine with hexacyclo[6.6.0.02,6.03,13.04,11.05,9]-tetradecan-10-one derivatives
Iodoketone 2 reacts with triphenylphosphine or triethyl phosphite to form phosphonium salts 3 and 7 which fragment to an iodide 4 upon heating. The mechanism of C–C bond formation induced by phosphine and phosphite is discussed. A 1,3,2-dioxaphospholane 8 was synthesized from diketone 1 in two steps through an intermediate diol 10, although an attempt for a direct condensation of 1 and triphenylphosphine was unsuccessful. The reaction is rationalized with the aid of semi-empirical calculations. Crystal diffraction analyses for 3 and 8 are reported and some of their bonding parameters are compared with the calculated values.