Tri-methyl-phosphine of high purity - is made by high yield grignard synthesis in medium of ether with high boiling point.

Abstract
Das Verfahren zur Herstellung von Trimethylphosphin, P(CH<3)<3, soll ein hoechstreines Endprodukt mit hoher Ausbeute liefern. Dies kann nach der erfindungsgemaessen Lehre durch direkte Destillation aus dem Reaktionsgemisch einer Methylierung von Triphenylphosphit, P(OC<6H<5)<3, erfolgen, fuer die durch den Einsatz eines hochsiedenden Ethers die Voraussetzung geschaffen wird. Die Reaktion laeuft nach der Gleichung 1 sein koennen. Die Ausbeute liegt zwischen 80% und 95%; Verunreinigungen waren nicht feststellbar. Das erzeugte Trimethylphosphin eignet sich als Quellsubstanz, insbesondere als Bestandteil eines vorgeformten Addukts, fuer MOVPE-Prozesse zum Schichten- und Strukturaufbau von InGaAsP/InP-Halbleitern.

 

DE 3612629 A UPAB: 19930922 The starting material is triphenylphosphite P(OC6H5) which is methylated in a medium consisting of an ether with a high b. pt. This is pref. (CnH2n+1)2O in which n is 3-10, e.g. di-n-butylether, or a polyether with the general compsn. R(OR')nO-R in which R is CnH2n+1 and R' is CnH2N while n is 1-10. The methylation agent used is a methylmagnesiumhalogenide CH3MgX in which X is Cl, Br or I, or methyllithium CH3Li. The methylation agent and triphenylphosphite, pref. dissolved in the same ether are mixed in a ratio of 1:03 and made to react, under shielding gas pref. high purity Ar. All reactions and preparations are carried out with air and moisture rigorously excluded and in very clean equipment. A process is also claimed. USE/ADVANTAGE - The process yield is higher than that achieved in a current, similar process, i.e. 80-95% compared with 78%. The sepn. of the prod. from the reaction mixt. is much simpler and less expensive. There is less danger of contamination. The process can be carried out with reagent quantities larger than possible in laboratory processing. The prod. is used for metal organic vapour phase. 0/0