829-83-4Relevant academic research and scientific papers
α-cationic arsines: Synthesis, structure, reactivity, and applications
Dube, Jonathan W.,Zheng, Yiying,Thiel, Walter,Alcarazo, Manuel
supporting information, p. 6869 - 6877 (2016/06/14)
A series of structurally differentiated cationic arsines containing imidazolium, cyclopropenium, formamidinium, and pyridinium substituents have been synthesized through short and scalable routes. Evaluation of the donor properties of these compounds by IR spectroscopy and DFT calculations reveals similar σ-electron-releasing abilities for all of them; however, their π-acceptor properties are strongly influenced by the nature of the positively charged group. We describe the coordination chemistry of the newly prepared α-cationic arsines toward different metal centers and their reactivity in the presence of strong oxidants to afford cationic As(V) species. Their unique electronic properties have been exploited in Pt(II) catalysis to develop a new catalyst with remarkable activity in the cycloisomerization of enynes to trisubstituted cyclopropanes. To the best of our knowledge, this is the first report on the use of α-cationic arsine ligands in catalysis.
Mechanistic variety in zirconium-catalyzed bond-forming reaction of arsines
Roering, Andrew J.,Davidson, Jillian J.,MacMillan, Samantha N.,Tanski, Joseph M.,Waterman, Rory
experimental part, p. 4488 - 4498 (2009/02/04)
Triamidoamine-supported zirconium complexes have been demonstrated to catalyze a range of bond-forming events utilizing arsines. Three different mechanisms have been observed in these reactions. In the first mechanism, triamidoamine-supported zirconium complexes of the general type (N 3N)ZrX (N3N = N(CH2CH2NSiMe 3)33-; X = monoanionic ligand) catalyzed the dehydrogenative dimerization of diphenylarsine. Mechanistic analysis revealed that As-As bond formation proceeds via σ-bond metathesis steps similar to the previously reported dehydrocoupling of phosphines by the same catalysts. In the second mechanism, sterically encumbered primary arsines appear to be dehydrocoupled via α elimination of an arsinidene fragment. Dehydrocoupling of dmpAsH2 (dmp = 2,6-dimesitylphenyl) to form (dmp)As = As(dmp) by (N3N)Zr-complexes appeared to proceed via elimination of dmpAs: from the arsenido intermediate, (N3N)ZrAsH(dmp) . Further support for α-arsinidene elimination came from the thermal decomposition of (N3N)ZrAsHMes (9) to (MesAs)4 (10), which obeyed first-order kinetics. In the third mechanism, the observation of stoichiometric insertion reactivity of the Zr-As bond with polar substrates, PhCH2NC, PhCN, (1-napthyl)NCS, and CS2, led to the development of intermolecular hydroarsination catalysis of terminal alkynes. Here, (N3N)ZrAsPh2 (2) catalyzed the addition of diphenylarsine to phenylacetylene and 1-hexyne to give the respective vinylarsine products. Arsenido complexes 2 and 9 and tetraarsine 10 have been structurally characterized.
CHEMIE POLYFUNKTIONELLER MOLECUELE XCI*. TRITERTIAERE ARSINE UND IHRE VERWENDUNG ALS BAUSTEINE ZUR SYNTHESE VON ARSENHALTIGEN CRYPTANDEN (BZW. SPHERANDEN)
Ellermann, Jochen,Veit, Adolf,Moll, Matthias
, p. 51 - 66 (2007/10/02)
Cl (V), 3>Cl (VII) and the 1,3,5-trithiacyclohexane derivative (CHS)3(CH2CH2Cl)3 (IX) react with NaAs(C6H5)2 in liquid ammonia to give N2CH2CH(CH3)As(C6H5)2 (VI), N3 (VIII) and (CHS)33 (X).Treatment of VI with HI results, under elimination of benzene, almost quantitatively in the formation of I (XI), which is recristallized from THF as I*THF (1/1) (XIa).All attempts to obtain homogeneous products by reaction of VIII or X with HI, such as 3>I and (CHS)3(CH2CH2AsI2)3, failed.With H2O/NH3 or H2S/N(C2H5)3 XIa forms the cryptands 8(As4O4)6 (XII) or 8(As4O4)6 (XIII), which also can be considered as spherands.All the new compounds are characterized, as far as possible, by their IR, Raman, 1H NMR and mass spectra.
