Page 1. SYNTHETIC COMMUNICATIONS, 27(23), 4035-4040 (1997) ... Acknowledgements: We thank Mrs. ACHTM van der Kerk for Kcording of the mass spectra and Mrs. ILM Groothuis for literature searching. References 1 . Meijer, J. and Vermeer, P. Red. Trw. Chim. ... Vol. ...