5240
Scheme 2.
The other path is regeneration of iminophosphorane 6 and HFA. The formation of the imino-
phosphorane is considered as a characteristic reaction of not only azaphosphetidines but also
oxazaphosphetidines.
In summary, we have succeeded in the synthesis and X-ray structural analysis of 1,3,2l5-oxaza-
phosphetidine bearing the Martin ligand. It was found by its thermolysis that oxazaphosphetidine
has two reactivities, respectively, as an oxaphosphetane and an azaphosphetidine.
Acknowledgements
This work was partially supported by Grants-in-Aid for Scienti®c Research from the Ministry of
Education, Science, Sports and Culture of Japan. We thank Professor T. Asano, Oita University,
for his generous gift of an authentic sample of hexa¯uoroisopropylideneaniline. We also thank
Central Glass and Tosoh Akzo Co. Ltd., for the gifts of organo¯uorine compounds and alkyl-
lithiums, respectively.
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