1-Trimethylsilylphosphirane, C2H4PSiMe3, has been prepared on a multi gram scale from P (SiMe3) 3via ClCH2CH2P (SiMe3) 2. C2H4PSiMe3 is readily susceptible to protonolysis forming the thermally unstable parent phosphirane, C2H4PH, in good yields. Reaction of C2H4PSiMe3 with fac-M (CO) 3 (CH3CN) 3 (M= Cr, Mo) or [Fe (η5-C5H5)(η6-C6H6)](PF6) give rise to fac-M (CO) 3 (C2H4PSiMe3) 3 and [Fe (η5-C5H5)(C2H4PSiMe3) 3](PF6) ...