Nuclear Magnetic Resonance (NMR) Spectroscopy. 1 H (400.160MHz) and 13 C (100.620MHz) spectra were recorded on a BrukerAvance400 III HD spectrometer. CDCl3 was used as solvent at room temperature. The 1 H NMR spectra were referenced to the residual signal of the nondeuterated solvent component (CDCl3 7.25 ppm). Peak assignments were made by NMR spectroscopy ( 1 H, P, 1 H-1 H-COSY).