A general route for the synthesis of triazacyclononane functionalised with one, two or three pendant phosphine arms: crystal structure of [Zn2L2Cl3][ClO4], L =N-(diphenylphosphinopropyl)-1,4,7-triazacyclononane

Ellis, David; Farrugia, Louis J.; Hickman, David T.; Lovatt, Paul A.; Peacock, Robert D.

doi:10.1039/cc9960001817

Cited by 19 publications

(7 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The 31 P{ 1 H} NMR spectra of [NP]ZnMe and [NP]ZnEt reveal a singlet resonance for the phosphorus donor at −27.34 and −27.15 ppm, respectively, which is shifted relatively upfield from that of H[NP] at −20.11 ppm. A similar upfield change in the 31 P chemical shift is also observed for (2,6- t Bu 2 C 6 H 3 O) 2 Zn(PCy 3 ) (−2.1 ppm) 14 and [(μ-Cl)(ZnLCl) 2 ][ClO 4 ] (−3.2 ppm, L = N -(diphenylphosphinopropyl)-1,4,7-triazacyclononane) as compared to the corresponding free phosphines. The coordination of the phosphorus donor of [NP] - to Zn is further supported by the 13 C{ 1 H} and DEPT 13 C NMR spectroscopy.…”

supporting

confidence: 69%

“…Crystallographically characterized phosphine derivatives of group 12 metals are rare. ,, Single crystals of [NP]ZnEt suitable for an X-ray diffraction study were grown from a concentrated diethyl ether solution at −35 °C. As depicted in Figure , [NP]ZnEt exists as a monomeric, three-coordinate species with the zinc atom surrounded by one ethyl group and the nitrogen and phosphorus donors of the amido phosphine ligand.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Amido Phosphine Complexes of Zinc

2003

View full text Add to dashboard Cite

show abstract

supporting

confidence: 69%

mentioning

confidence: 99%

Amido Phosphine Complexes of Zinc

2003

View full text Add to dashboard Cite

show abstract

“…Though 2a was not isolable due to concomitant formation of 4a, its identity was deduced by 1 H and 31 P{ 1 H} NMR spectra of product mixtures in comparison with those of 2b-d and 4a, respectively. Interestingly, the 31 24 as compared to their corresponding free phosphines. Consistent with the coordination of the phosphorus donors, the H a and C a atoms in these alkyl complexes exhibit a diagnostic coupling where resolved, e.g., 3 J PHa = 4.2 Hz for 2c and 2 J PCa = 37 Hz for 3d, in the 1 H and 13 C{ 1 H} NMR spectra.…”

Section: Nmr Studiesmentioning

confidence: 99%

Amido phosphine complexes of zinc: synthesis, structure, and catalytic ring-opening polymerization of ε-caprolactone

et al. 2010

View full text Add to dashboard Cite

A series of diarylamido phosphine ligands of the type N-(2-dihydrocarbylphosphinophenyl)-2,6-dialkylanilide 1a-d have been prepared and employed to investigate the coordination chemistry of zinc. Protonolysis of ZnMe2 with one equivalent of N-(2-diphenylphosphinophenyl)-2,6-dimethylaniline (H[1a]) produced a mixture of [1a]ZnMe (2a) and Zn[1a]2 (4a), whereas that involving ZnEt2 gave exclusively the three-coordinate [1a]ZnEt (3a). In contrast, treatment of ZnR2 (R = Me, Et) with N-(2-diphenylphosphinophenyl)-2,6-diisopropylaniline (H[1b]), N-(2-diisopropylphosphinophenyl)-2,6-dimethylaniline (H[1c]), or N-(2-diisopropylphosphinophenyl)-2,6-diisopropylaniline (H[1d]) under similar conditions generated quantitatively the corresponding three-coordinate zinc methyl 2b-d and zinc ethyl 3b-d. The bis-ligand complexes 4a,b,d were isolated by either protonolysis of alkyls 2-3 with one equivalent of H[1] or metathesis of ZnX2 (X = Cl, OAc) with the corresponding lithium derivatives 5. Attempts to prepare [1a-d]ZnX (X = Cl, OAc) were not successful regardless of stoichiometry of the starting materials employed. Alcoholysis of zinc alkyls 2-3 led undesirably to protonation on the amido nitrogen donor of 1, highlighting perhaps its higher basicity than alkyls. The reaction of ZnCl2 with H[1c] generated the phosphorus-bound adduct {H[1c]ZnCl(mu-Cl)}2 (6c). Interestingly, attempts to deprotonate 6c with n-BuLi produced unexpectedly the alkylated product [1c]Zn(n-Bu) (7c) instead of [1c]ZnCl; analogous reactions employing NEt3 led to Lewis base substitution to give H[1c] and [ZnCl2(NEt3)]2. Structural characterization of all new compounds was achieved by multi-nuclear NMR spectroscopy (1H, 13C, 31P, and 7Li) and X-ray crystallography (2c-d, 3c, 4d, 5c-d, and 6c) where appropriate. On the basis of the NMR and X-ray data, in combination with the synthetic investigations, the steric nature of these amido phosphine ligands is recognized to follow the order of 1a < 1b < 1c < 1d. Interestingly, zinc alkyls 2-3 are all active initiators for catalytic ring-opening polymerization of ε-caprolactone whereas the bis-ligand complexes 4 are not.

show abstract

“…and the other is formally five (N 3 PCl-) co-ordinate but with a weak interaction (2.91 Å) to one of the two chlorides of the pseudooctahedral zinc centre. 20 The change in 31 P chemical shift upon co-ordination of L 5 to zinc is small (∆δ P = Ϫ3.2), 20 typical for other examples of phosphine co-ordination to zinc() ion. 20, 40 Thus the 31 P data for "ZnCl(H 2 O)(L 2 )(PF 6 )" are consistent with structures for the cation in which the phosphine binds zinc such as [ZnCl(κN 3 ,κP-L 2 )] ϩ (A).…”

Section: Coppermentioning

confidence: 99%