| Abstract
| - The preparation of a new family of acyclic DippN(H)P(Ph)NRCR‘NR systems (2a−c) hasbeen achieved by the reaction of the mono(amino)chlorophosphine PhP(Cl)N(H)Dipp (1; Dipp= 2,6-(iPr)2C6H3) with 1 equiv of Li[CR‘(NR)2] (2a, R = tBu, R‘ = nBu; 2b, R = Cy, R‘ = tBu;2c, R = Cy, R‘ = nBu). Metalation reactions of 2a−c using nBuLi, Me3Al, and Bu2Mg haveshown that the NPNCN backbone is susceptible to nucleophilic attack. Reactions of 2a or2b with nBuLi or Me3Al, respectively, produce the complexes Li[DippNPhP−P(nBu)PhNDipp]·Et2O (3) and Al(Me)2[DippNPhP−P(Me)PhNDipp] (4). These complexes involve a new typeof N,N‘ bidentate ligand with a chiral phosphorus center bearing bulky organic substituentson the nitrogen atoms. Reaction of 2c with Bu2Mg proceeds in a different manner, producingthe amidinate complex Mg[CyNC(nBu)NCy][DippNP(nBu)Ph]·Et2O (5). A more direct routeto 3 and the analogous methyl-substituted complex Li[DippNPhP−P(Me)PhNDipp]·Et2O (6),involving the reaction of 1 with the appropriate organolithium reagent in the molar ratio2:3, has been developed. The oxidation product of 3, {Li[DippNPhP(O)P(nBu)PhNDipp]}2(7), has also been synthesized via an alternative route. Complexes 1, 2a,b, and 5−7 werefully characterized by multinuclear NMR spectroscopy, elemental analysis, and X-raycrystallography.
- The preparation of a new family of acyclic NPNCN systems has been achieved by the reaction of the PhP(Cl)NHDipp with 1 equiv of Li[CR‘(NR)2]. Metalation reactions of these species using nBuLi, Me3Al, and Bu2Mg have shown that the NPNCN backbone is susceptible to nucleophilic attack. Reactions with nBuLi or Me3Al generate the complexes Li[DippNPhP−P(nBu)PhNDipp]·Et2O and Al(Me)2[DippNPhP−P(Me)PhNDipp]. Reaction with Bu2Mg proceeds differently, producing the amidinate complex Mg[CyNC(nBu)NCy][DippNP(nBu)Ph]·Et2O.
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