P-H-functionalised phosphinocyclopentadienes: 1-SiMe2PHCy-2,3,4,5-Me4C5H, Li-2[(C5Me4)SiMe2PCy], Li[(C5H4)CMe2PHPh] and Li-2 [(C5H4)CH2CH2PPh]

Several P-H-functionalised phosphinocyclopentadienes and lithium salts ther eof were prepared: 1-SiMe2PHCy-2,3,4,5-Me4C5H (1) (Cy=C6H11), Li-2[(C5Me4)S iMe2PCy] (1a), Li[(C5H4)CMe2PHPh] (2) and Li-2[(C5H4)CH2CH2PPh] (3). 1 was obtained from 1-SiMe2Cl-2,3,4,5-Me4C5H and LiPHCy. Treatment of 1 with MeLi yields the corresponding dilithio salt 1a. 6,6-Dimethylfulvene reacts with LiPHPh to give 2. The three-membered ring of spiro[2,4]hepta-4,6-diene is cleaved by LiPHPh. Successive treatment of the intermediate monolithio salt with MeLi gives 3. Compounds 1-3 were characterised spectroscopically (H-1 , P-31, C-13, Li-7 NMR; IR). (C) 1999 Elsevier Science Ltd. All rights rese rved.