Reactions of β-diketiminates with selenium and tellurium halides

2011

Dalton Trans.

The direct reactions of PI(3) with -H or -C(6)H(5) substituted diiminopyridine ligands yield the N,N',N''-chelated P(I) cations. The analogous chemistry with the ubiquitous -CH(3) substituted derivative produces a complex mixture of products underscoring the importance of the substitution on the α-carbon atom. The I(3)(-) counteranion of the compounds could be easily exchanged with the more robust B(12)Cl(12)(2-) dianion. Reactions of PCl(3) and PBr(3) with -CH(3) and -C(6)H(5) substituted ligands led to indiscernible mixtures or no reaction. However, heating PBr(3) with the -H derivative in the presence of a halide trap produced the corresponding phosphorus(I) cation as the bromide salt. These species represent the first phosphorus diiminopyridine complexes reported.

Section: General Proceduresmentioning

confidence: 99%

“…for RDIMPY 1¢). [12][13][14][15][16] Despite the vast amounts of P-N chemistry in the literature, phosphorus surprisingly lacks an RDIMPY complex. Although not observed with arsenic, we surmised that the related enamine chemistry could proceed with phosphorus.…”

Section: Introductionmentioning

confidence: 99%

Substitution matters: isolating phosphorus diiminopyridine complexes

Martin

2011

Dalton Trans.

“…Godfrey et al has taken advantage of Ph 4 Se 4 X 4 (X = Br, I), which acts as a source of a Se(II)-like synthon “PhSeX” (Scheme a). This work has clearly shown that resilient coordinative P→Ch bonding in solution is possible. , In a similar vein, Richards et al have demonstrated that N→Se bonding is also viable by employing the NacNac class of ligands; however, the moderate to low yields, as well as chlorination of the ligand set, underscores the propensity for chalcogen halides to undergo redox chemistry in the presence of strong Lewis bases (Scheme b). , …”

Section: Introductionmentioning

confidence: 67%

Donor−Acceptor Chemistry at Heavy Chalcogen Centers

Dutton

2009

Inorg. Chem.

A series of coordination complexes, where a heavy chalcogen (Se, Te) acts as the acceptor site, using a variety of electron rich Lewis bases (phosphine, imine, N-heterocyclic carbene), have been synthesized and comprehensively characterized. Each derivative is a representative example of a E-->Ch coordinative bond, characterizing an efficient E-E bond forming methodology and a systematic investigation into the coordination chemistry of the chalcogens. The complexes are susceptible to classic ligand exchange reactions, verifying the dative E-->Ch bonding motif.

“…Reactions of the same ligand with the chalcogen tetrahalides SeCl 4 , SeBr 4 , TeBr 4 , TeCl 4 resulted in complex mixtures, which were not further investigated. It has been established in related work that the chalcogen halides are susceptible to releasing X 2 in the presence of strong Lewis bases, subsequently degrading what is present in solution, which includes the ligand. − …”

Section: Resultsmentioning

confidence: 99%

Reactions of Diiminopyridine Ligands with Chalcogen Halides

Martin

2012

Inorg. Chem.

The reactions of the chalcogen halides (Ch = S, Se, Te) with a series of diiminopyridine (DIMPY) ligands were explored. It was determined through these studies that varying both the substitution on the α-carbon and the chalcogen halide reagent afforded different products. If methyl groups were present on the α-carbon, reactivity was observed through the eneamine tautomer to yield N,N',C-bound neutral chalcogen complexes. In the cases where H and C(6)H(5) groups were in the same position, N,N',N″-chelated chalcogen cations or dications were produced. Many of the reactions resulted in complex mixtures postulated to occur by the release of halogen decomposing the product or, for reactions with the CH(3) substituted ligand, uncontrollable reactivity with the eneamine tautomer. This is the first report of reactions of sulfur and selenium halides with the ubiquitous diiminopyridine ligands and only the second example for a tellurium halide.