Chemical reaction
In organophosphorus chemistry, the Kinnear–Perren reaction (sometimes the Clay-Kinnear-Perren reaction) is used to prepare alkylphosphonyl dichlorides (RP(O)Cl2) and alkylphosphonate esters (RP(O)(OR')2).[1] The reactants are alkyl chloride, phosphorus trichloride, and aluminium trichloride as catalyst.[2] The reaction proceeds via the alkyltrichlorophosphonium salt:
- RCl + PCl3 + AlCl3 → [RPCl3]+AlCl4−
Reduction of this trichlorophosphonium intermediate with aluminium powder gives alkyldichlorophosphines (RPCl2).
Partial hydrolysis of the same intermediate gives the alkylphosphonyl dichloride:
- [RPCl3]+AlCl4− + H2O → RP(O)Cl2 + AlCl3 + 2 HCl
The reaction was first reported by Clay[3] and expanded upon by Kinnear and Perren, who demonstrated that the four chlorinated methanes (CH4−xClx) give the corresponding CH3-, CH2Cl-, CHCl2-, and CCl3-substituted derivatives. They also demonstrated workup with hydrogen sulfide to give the alkylthiophosphoryl dichlorides.[4]
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