Cage Compounds of Phosphorus and Silicon

Triane-type cages are obtained in reactions (9.230) through (9.232) [30]. 

SiMe2 —SiMej v P. SiMe2 — SiMej P + 3NaCI SiMe2 —SiMe/ 

The action of heat on P4(8iMe2)3 secures transformation to the adamantane-type compound, (Me28i)6P4 (9.238), as in Equation 9.231. It is stable up to 400°C. A similar adamantane cage with the 8i and P atoms reversed can be obtained as indicated in Equation 9.239 [31]. 

Another adamantane-type compound is obtained by reaction (9.242). The reactions of methyl-chlorosilanes with LiPH2 and Li2PH lead to a whole series of ring and cage compounds built from P-8i linkages [32]. 

Methanolysis of these compounds in many cases produces phosphorus hydrides (Chapter 4.4). 

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