Triethyl phosphite → Diethyl (3-ethylisoxazol-5-yl)-methanephosphonate
Reaction equation
Cl[CH2:2][C:3]1[O:7][N:6]=[C:5]([CH2:8][CH3:9])[CH:4]=1.[P:10]([O:17]CC)([O:14][CH2:15][CH3:16])[O:11][CH2:12][CH3:13]>>[CH2:12]([O:11][P:10]([CH2:2][C:3]1[O:7][N:6]=[C:5]([CH2:8][CH3:9])[CH:4]=1)(=[O:17])[O:14][CH2:15][CH3:16])[CH3:13]Participants
3
Procedure
15 g of 5-chloromethyl-3-ethyl-isoxazole and 18 g of triethyl phosphite are slowly heated to 150° C. and left at this temperature for 21/2 hours. After the mixture has cooled, it is distilled under reduced pressure. 18.2 g of (3-ethylisoxazol-5-yl)-methanephosphonic acid diethyl ester of boiling point 120°-121° C./0.2 mm Hg are obtained. Yield: 71.2%. 1H-NMR spectrum (CDCl3, with TMS as internal standard): τ=3.85 (d, J=3 Hz, 1H), 4.17 (m, J=Hz, 4H), 6.60 (d, H=20 Hz, 2H), 7.35 (q, J=Hz, 2H), 8.50-8.93 (m, 9H)
Workup
- temperatureAfter the mixture has cooled
- distillationit is distilled under reduced pressure