| 摘要 |
<p>In a new process for the prodn. of thiophosphonic acid O-ester chlorides of formula (I) by reaction of corresp. dithiophosphonic acid O-esters of formula (II) with Cl2 and separating precipitated sulphur from the reaction prod. (where R and R1 are organic residues). (a) (II) is reacted with ca. 1.5 molar proportions of Cl2 to give a mixt. of (I) and S2Cl2; (b) this mixt. is treated with about the same amt. of (II) as was used in step (a) so as to yield a mixt. of (I), bis-O-alkylthiophosphenyl disulphide of formula (III) and sulphur; (c) the crystalline sulphur is filtered off; (d) (I) and any inert solvent used are distilled off from (III); (e) the disulphide (III) is reacted with ca. 2 molar proportions of Cl2 to give a mixt. of (I) and S2Cl2; and (f) this mixt. is either reacted with (II) as in step (b) or reacted with H2S to convert the S2Cl2 into S + HCl, (I) being subsequently distilled off from the sulphur. (I) are intermediates, especially for plant protection agents. By carrying out the process in the specified manner, by prod. sulphur is obtd. in crystalline form and is therefore easily sepd. off. The chlorine is fully utilized. (I) is obtd. in good yield and high purity.</p> |
