(N-lithioamino)diorganophosphanes and Bis(N-Lithioamino)organophosphanes: Synthesis and Structures

Triaminoboranes and Their Metallation toN-Lithiotriaminoboranes

“…Therefore, in comparison with lithium amides, [16,17] the borylated lithium amides offer a much more versatile structural chemistry similar to that of lithiated silylamides [16] and aminophosphanes. [47] In addition, they are very useful reagents. This has been shown previously, [5Ϫ10,48] and we will report on this point in a forthcoming paper describing the synthesis and reactions of (tBuLiN)B(R)tmp (tmp ϭ 2,2,6,6-tetramethylpiperidino) (see ref.…”

Synthesis and characterization of palladium(II) complexes with chiral aminophosphine ligands: Catalytic behaviour in asymmetric hydrovinylation. Crystal structure of cis-[PdCl2(PPh((R)-NHCHCH3Ph)2)2]

“…1 H spectra of the bisaminophosphine ligands (d, e) show two signals for CH 3 groups coupled to the methinic proton, two complex multiplets for the CH proton and two different broad signals for the NH proton of amino groups coupled to the phosphorus atom as confirmed by 1 H-{ 31 P} experiments. It has been noted that hindered rotation about the P-N bond may exist as reported in the literature [27]. It is known that monoaminophosphines and bisaminophosphines bearing primary amino groups exist in tautomeric equilibrium with PH-iminophosphines and that bisaminophosphines also are amenable to condensation [27].…”

“…It has been noted that hindered rotation about the P-N bond may exist as reported in the literature [27]. It is known that monoaminophosphines and bisaminophosphines bearing primary amino groups exist in tautomeric equilibrium with PH-iminophosphines and that bisaminophosphines also are amenable to condensation [27]. NMR spectra allowed us to observe that freshly prepared samples did not contain significant amounts of condensation products and that the position of the prototropic equilibrium is displaced significantly towards the NH form.…”

A monomeric N,N′-dilithiobis(amido)organophosphane

“…Several examples have been synthesized, and the effect of the organic substituents R and R 0 on the observed solid-state structure has been investigated (Eichhorn et al, 1999). It has been shown that the use of less sterically-hindered organic groups can lead to formation of larger oligomers; for example, in the case of R = R 0 = Ph, the structure is dimeric, whereas for smaller substituents R = Me, R 0 = i Pr, a tetramer is observed.…”

“…Complex (I) contains a pyramidal phosphorus centre, bonded to one phenyl group and two imido nitrogen centres. The P-N bond lengths (Table 1) are slightly different and can be considered as single bonds, falling at the upper end of the observed range for compounds of the type Li 2 [RP(NR 0 ) 2 ] [1.656 (5)-1.715 (2) Å ; Eichhorn et al, 1999]. The N atoms are each coordinated to two lithium centres with a total of four N-Li bonds.…”