127I Mössbauer spectra for phenyliodonium ylides

¹²⁷I Mössbauer spectra for the phenyliodonium ylides were measured at 20 K. The valence electron populations (N_s, N_x-z) and the charge number (Z_I) for iodine atom are estimated from the Mössbauer parameters. The obtained populations were very close to those of diphenyliodonium chloride having two I-C primary bonds. To examine the possibility of some double bond character, the electron populations for the case of N_z = 1.90 are estimated. In this case, the Z_I values become larger as 1.2-1.3, and these values were unreasonably large because the values are close to those of PhICl₂, PhI(OAc)₂ having electron withdrawing ligands. Thereby, ¹²⁷I Mössbauer parameters suggest little double bond character for phenyliodonium ylides.