摘要:
H-1 and P-31 dynamic NMR, vibrational spectroscopy, and consideration of dipole moments have shown that 2-chloro-2-thiono-4,5;7,8-dibenzo(4,4'-dimethyl-6,6'-di-tert-butyl)-1,3,2-dioxaphosphocene and its 2-ethoxy derivative are conformationally heterogeneous. The former exists as a three-component equilibrium mixture, and the latter as a two-component equilibrium mixture. In the chlorothiophosphate the boat-chair conformation predominates, with equatorial location of thiophosphoryl; next in frequency is boat-chair with axial orientation of P = S, and third is the deformed boat form. In the ethyl thiophosphate the preponderant form is the deformed boat with thiophosphoryl in the equatorial position.