The Synthesis and Crystal Structure of ( / ? * , / ? * ) - ( ± ) - [ ( i / 5 - C 5 H 5 ) { 1 , 2 -

Primary and secondary phosphine complexes are convenient precursors of terminal phosphido-metal compounds by deprotonation. Recent work has shown that the chiral tertiary phosphido-metal group Fe —PMePh can be generated stereospecifically by deprotonation of a resolved secondary phosphine complex at —90 °C, and, furthermore, that it can be alkylated with retention of configuration and com­ plete stereoselectivity at that temperature [1 , 2 ]. Here we report the synthesis of (/?*,R *)-(± C5H 5){l,2-C 6H4(PMePh)2}Fe(PCl3)]Cl-2M eCN [3] and its crystal structure. The enantiomers of this compound are potential precursors of optically active phosphine complexes containing the Fe+<—PH 3 group, which we intend to investigate as sources of optically active tertiary phosphine complexes (Fe+<— P R 'R 2R ) by asymmetric synthesis. To our knowledge, this is the first structurally authenticated iron-phosphorus trichloride complex. The title complex was isolated by recrystallization from acetonitrile of the product obtained from the reaction between (/?*,/?*)-(±)-[(//;'-O H :s){ 1,2CftH4(PMePh)2}Fe(NCMe)]PF6 [4] and excess PC13 in boiling tetrahydrofuran (20 h under reflux). The