| 摘要 |
<p>Prepn. of 2-fluorovinyl-phosphorus (V) cpds. having formula (I) is claimed: (where R1 is 1-12C alkyl, or aryl if a=0; R2 is 1-12C alkyl, or aryl if b=0; X is -O- or -S-; and a and b are 0 or 1). (I) prepd. by dehydrofluorination of 2,2-difluoroethyl-P(V) cpds. having formula: R1(-O)a R2(-O)b P(=X)-CH2CHF2 (II), with strong to medium strong bases, in aq. or alcoholic media. The 2-fluorovinyl phosphonates and phosphinates can be saponified to the free acids or converted with phosgene to acid chlorides. The acids and acid chlorides are intermediates for prepn. of plant protective agents. The esters can be used for prepn. of difficulty inflammable copolymers, prepn. of flame-resistant fabric finishes and of flame-resistant thermoplastic articles generating little smoke on burning. In an example dimethyl 2-fluorovinyl phosphate was prepd. by adding 44g 55% NaOH soln. to a mixt. of 87g dimethyl 2,2-difluoromethane phosphonate, at -10 degrees C in 2 hrs. Yield:74% of theoretical. B.pt.10 80-83 degrees C.</p> |
