STRUCTURE OF 1-YL)BIS(1,2-BIS(DIMETHYLPHOSPHINO)ETHANE)IRON(II)

An iron(II) bisacetylide complex containing conjugated 3-methylbut-3-e n-1-yn-1-yl ligands has been synthesized and characterized. The struct ure consists of a neutral -[Fe{C=CC(CH3)=CH2}(2){Me(2)PCH(2)CH(2)PMe(2 )}(2)] molecule with iron located at a centre of symmetry. The Fe-P bo nd lengths {2.184(1) Angstrom} are the same as those in the analogous propyne complex {2.183(1) degrees)}and phenylacetylide complex {2.180( 5) and 2.191(3) Angstrom}, and are indicative of low-spin iron(II). Th e Fe-C distance is 1.905(4) Angstrom.