ZUR DARSTELLUNG P-1-ADAMANTYL-SUBSTITUIERTER PHOSPHAALKENE

Abstract

1-Adamantylphosphine 1 did not react with fluorenone in the presence of BF₃-etherate to give the desired phosphaalkene. Instead, addition of 1 at the C[dbnd]O-bond and complexation of BF₃ by the lone pair at phosphorus with formation of the co-ordinated α-hydroxyphosphine 2 took place. The P-I-adamantyl-substituted phosphaalkene 1-AdP[dbnd]C(OSiMe₃)'Bu 6 was synthesized in the reaction of equimolar quantities of 1-adamantyl-bis-trimethylsilylphosphine 4 and pivaloyl chloride. In the reaction mixture, the E/Z-isomers E-6 and Z-6 were observed by ³¹P-NMR-spectroscopy. Prolonged heating of the reaction mixture at 40°C led to isomerisation, giving exclusively the E-isomer E-6.

Key Words:

• 1-Adamantylphosphine
• 1-Adamantyl-bis-trimethylsilylphospnine
• Phosphaalkene
• E/Z-Isomers