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- Melting points were obtained on a melt temp melting point apparatus and are uncorrected. The elemental analyses were performed by Galbraith Laboratories, Knoxville, TN and Petrolite Corporation, Analytical Section. 1H NMR spectra were obtained with a Perkin-Elmer R-32 spectrometer (90 MHz). 31P and 13C spectra were obtained with a Jeol FX-60 spectrometer operating at 24.15 and 15.04 MHz, respectively. The chemical shift (+ δ) values are downfield from H3PO4 (cap.) for 31P spectra and from Me4Si for 13C spectra
- Russian workers isolated 3a as tetracyclohexylammonium salt and 3b as tricyclohexylammonium salt. We found that dianilinium salts 3a and 3b were more readily purified by crystallization. Tricyclohexylammonium salt of 3b prepared by us had significantly higher melting point than that reported in ref. 5. Tricyclohexylammonium salt of 3b: mp 214–215°C (lit.5 mp 142–143°C). 13C NMR (D2O/Me4Si cap.) δ 18.99 (d, J=2.44 Hz), 24.92, 25.48, 31.49, 51.46, 69.48 (dd collapsing to t, J=4.88 Hz), 72.15 (dd, J=4.88 Hz, 7.32 Hz). 31p NMR (D2O/H3PO4 cap.) δ 1.26 (d, J=8.54 Hz, CHOP), 2.58 (t, J=7.32 Hz, CH2OP). Anal, calcd for C21H49N3O9P2: C, 47.28; H, 9.19; N, 7.88; P, 11.63. Found: C, 46.84; H, 9.35; N, 7.98; P, 11.70