Acetamide → (1-Aminoethylidene)bisphosphonic acid

HRID 1649531Notes

Reaction equation

[C:1]([NH2:4])(=O)[CH3:2].O1P2[O:11][P:12]3[O:14]P(O2)OP1[O:13]3.OO>C(O)C.O.C(#N)C.C(O)(=O)C>[NH2:4][C:1]([P:12]([OH:11])(=[O:13])[OH:14])([P:12]([OH:14])(=[O:11])[OH:13])[CH3:2]

Participants

Conditions

Temperature: 163 °C

Procedure

83.6 g (1.416 mols) acetamide was dissolved at about 40° C. in 45.4 g (1.1 mols) acetonitrile in a flask which was provided with a stirrer and had a fractionating column mounted thereon. Next, 52 g (0.236 mol) P4O6 was added dropwise at 40°-55° C. After this had been done, the temperature of the reaction mixture was gradually increased to 163° C. while 85.4 g distillate containing 96.4% acetonitrile and 3.5% acetic acid, corresponding to 82.3 g (2.008 mols) acetonitrile and 3.0 g (0.05 mol) acetic acid, was removed at a head temperature of 81°-85° C. After deduction of the acetonitrile feed material, 36.9 g (0.908 mol) acetonitrile was found to have been formed as a by-product. The yellow residue retained in the flask was oxidized with H2O2 and boiled in an ethanol/water-mixture (4:1). 60.1 g colorless crystalline 1-aminoethane-1,1-diphosphonic acid, corresponding to a yield of 60%, was obtained.

Workup

customwas provided with a stirrer
customto have been formed as a by-product

Sources & evidence

ORD record: ord-c9017d88e9d24505b7b69a0e4e2688db
Source dataset: uspto-grants-1983_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04418019

Reaction notes

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