Abstract
Ultrasonic irradiation on N‐phosphoryl‐serine and ‐threonine in acetonitrile at 30°C, 8 and 3 hr, yielded 82% and 86% O‐phosphoryl‐serine and ‐threonine, respectively.
Acknowledgment
We thank the financial supports from the Chinese National Natural Science Foundation (No. 20132020), The Ministry of Science and Technology, The Chinese Ministry of Education and Zhengzhou University.
Notes
aSpectral data for the representative products (3a) 31P NMR (400 MHz, CDCl3), δ 5.85; 1H NMR (400 MHz, CDCl3), δ 1.28 (d, J = 6.16 Hz, 12H), 3.86 (d, J = 3.84 Hz, 2H), 3.90 (br, 1H), 4.12 (dd, J = 4.28 Hz, 1H), 4.51 (br, 1H), 4.62 (m, 2H), 11.94 (br, 1H); 13C NMR (400 MHz, CDCl3), δ 23.70, 56.17, 64.43, 71.90, 173.76; ESI‐MS: 270 (M + H)+, 292 (M + Na)+. (3b) 31P NMR (400 MHz, CDCl3), δ 6.19; 1H NMR (400 MHz, CDCl3), δ 1.26 (d, J = 6.08 Hz, 12H), 1.34 (d, J = 4.78 Hz, 3H), 4.06 (m, 1H), 4.12 (dd, J = 4.48 Hz, 1H), 4.26 (br, 1H), 4.59 (br, 1H), 4.62 (m, 2H), 10.56 (br, 1H); 13C NMR (400 MHz, CDCl3), δ 19.13, 23.65, 59.65, 68.56, 71.86, 174.48; ESI‐MS: 284 (M + H)+, 306 (M + Na)+. (4a) 31P NMR (400 MHz, CDCl3) δ −2.78; 1H NMR (400 MHz, D2O), δ 1.16 (d, J = 6.26 Hz, 12H), 3.95 (m, 2H), 4.19 (m, 1H), 4.35 (d, J = 6.36 Hz, 2H); 13C NMR (400 MHz, D2O), δ 22.6, 60.7, 67.7, 69.4, 177.0; ESI‐MS: 270 (M + H)+, 292 (M + Na)+. (4b) 31P NMR (400 MHz, CDCl3), δ −3.881; 1H NMR (400 MHz, D2O), δ 1.15 (d, J = 6.24 Hz, 12H), 1.25 (d, J = 6.33 Hz, 3H), 3.91 (m, 2H), 4.24 (m, 1H), 4.35 (d, J = 6.35 Hz, 1H); 13C NMR (400 MHz, D2O), δ 14.7, 22.6, 65.3, 67.7, 72.5, 176.0; ESI‐MS: 284 (M + H)+, 306 (M + Na)+.