Phosphabicyclohexane oxides

It is recalled that the dihydrophosphinine oxides (e.g. 10) are obtained by the thermolysis of phosphabicyclohexane oxides (e.g. 2). It was also possible to obtain hexahydrophosphinine oxides (31) directly from the phosphabicyclohexane oxides (2), but somewhat more forcing conditions had to be applied during the hydrogenation (Scheme 15) [29],... 

Several aryl phosphabicyclohexane oxides (58) were readily deoxygenated to the corresponding phosphines (59) with retention of P-configuration. In one case... 

It was quite interesting that in the case of 3 having a 2,4,6-triisopropylphenyl substituent on the phosphorus atom, partial opening of the cyclopropane ring of the initially formed phosphabicyclohexanes (4t and 42) resulted in the corresponding 1,2-dihydrophosphinine oxide (52) (Scheme 2) [18],... 

Thermolysis of the tri-te/t-butylphenyl phosphabicyclohexane (12) led to dihydrophosphinine oxides 13t and 132. As can be seen, the opening of the cyclopropane ring was accompanied by the loss of the te/t-butyl group in position 4 (Scheme 7) [16],... 

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