Steering of Configuration by (2‐Phosphanyl)phenolato Ligands in Trimethylphosphane Iron Complexes

(Diphenylphosphanyl)phenols C 6 H 3 (1‐OH)(2‐PPh 2 )(4‐R 1 )(6‐R 2 ), abbreviated as (P ∧ OH), oxidatively add to Fe(PMe 3 ) 4 affording hydridoiron(II) compounds fac ‐FeH(P ∧ O)(PMe 3 ) 3 ( 1 : R 1 =R 2 =H; 2 : R 1 =Me, R 2 =H; 3 : R 1 =OMe, R 2 =H; 4 : R 1 =Me, R 2 =CMe 3 ; 5 : R 1 =R 2 =CMe 3 ) with high stereoselectivity. (2‐diphenylphosphanyl)thiophenol (P ∧ SH) reacts accordingly forming fac ‐FeH(P ∧ S)(PMe 3 ) 3 ( 9 ). Complete assignment of 1 H, 13 C, and 31 P signals is achieved by 2D heteronuclear shift correlations. 4,6‐Di‐ tert ‐butyl‐(2‐diphenylphosphanyl)phenol reacts with FeI(Me)(PMe 3 ) 4 to form FeI(P ∧ O)(PMe 3 ) 2 ( 6 ). 4 , 5 and 9 under 1 bar of CO are converted to monocarbonyl derivatives FeH(P ∧ X)(CO)(PMe 3 ) 2 ( 7 , 8 : X = O; 10 : X = S) which in solution form mixtures of two isomers A and B . 4 and 5 react with their parent phosphanylphenols, respectively, to give diamagnetic complexes Fe(P ∧ O) 2 (PMe 3 ) ( 11 , 12 ) which dissociate trimethylphosphane to give paramagnetic compounds Fe(P ∧ O) 2 . The same phosphanylphenols react with FeCl 3 to afford racemic mixtures of complexes Fe(P ∧ O) 3 ( 13 , 14 ). Structural data were also obtained from single crystals of compounds 1 , 5 , and 11 .