DFT calculations indicate that contrary to a prior report, N-heterocycle-augmented constrained geometry ligands e.g. Cp'-SiMe(2)-NR (Cp' = Me(4)C(5), R = 2-pyridine) should be capable of binding both atoms of the diazaallyl fragment at zirconium. This was confirmed by a molecular structure of a previously reported complex. Similar R = 2-oxazoline complexes were also shown to be feasible, althou...

A series of aluminum complexes supported by o-phenylene-derived amido phosphine ligands, N-(2-diphenylphosphinophenyl)-2,6-dimethylanilide ([Me-NP]-) and N-(2-diphenylphosphinophenyl)-2,6-diisopropylanilide ([iPr-NP]-), have been prepared. The reactions of trialkylaluminum with H[Me-NP] and H[iPr-NP], respectively, in refluxing toluene produced the corresponding dialkyl complexes [Me-NP]AlR(2) ...

Monosilicon analogs of phenolates and phenylthiolates are studied by quantum chemical calculations. Three different silaphenolates and three different silaphenylthiolates are possible; the ortho-, meta-, and para-isomers. For the silaphenolates, the meta-isomer is the thermodynamically most stable, regardless if the substituent R at Si is H, t-Bu or SiMe(3). However, with R = H and SiMe(3) the ...

This paper re-examines the labor supply responses in the Seattle and Denver Income Maintenance Experiments (SIME/DIME). Specifically, the original experimental results show a larger labor supply response for men and women from dual-headed households in the five-year treatment relative to those in the three-year treatment. Although typically thought of as a Negative Income Tax (NIT) Experiment, ...

The reaction of N(3)(CH(2))(3)Si(OTMS)(3) (TMS = SiMe(3)) with a dialkylammonium having hexynyl group 1, [FcCH(2)NH(2)CH(2)C(6)H(4)-4-O(CH(2))(4)C≡CH]PF(6) (Fc = Fe(C(5)H(4))(C(5)H(5))), in the presence of dibenzo[24]crown-8-ether (DB24C8) and [Cu{Fe(CN)(4)}]PF(6) catalyst yielded the [2]rotaxane containing the dialkylammonium unit terminated by a bulky silyl group. Azides with a silsesquioxane...

Multiobjective combinatorial optimization problems in various disciplines remain to be the focus of extensive research due to their inherent hard nature and difficulty of finding near-optimal solutions. Iterative heuristics like Tabu Search (TS) and Simulated Evolution (SimE) have successfully been employed to solve a range of such optimization problems [1]. These heuristics are able to obtain ...

Group 4 metal complexes [M(eta(5)-C(5)Me(4)SiMe(2)-eta(1)-N-2R)(NMe(2))(2)] (R = pyridine, pyrazine, pyrimidine, thiazole, M = Ti; R = pyridine, thiazole; M = Zr) containing the tetramethylcyclopentadienyl-dialkylsilyl bridged amidinato as pendant ligand, were synthesized and characterized by elemental analysis, solution (1)H, (13)C and (15)N NMR spectroscopy and experimental (13)C and (15)N CP...

The C-alkyl groups of C-alkylpyrazinium-derived ligands have been selectively deprotonated by K[N(SiMe(3))(2)], through charge-controlled processes, to give neutral products that contain C-alkylidenepyrazine-derived ligands.

Abstract The Staudinger reaction of 2,5‐bis((di‐ tert ‐butylphosphaneyl)methyl)‐1 H ‐pyrrole ( t Bu PNP)H; PNP=C 4 2 N‐2,5‐CH P ) with equiv. Me 3 SiN cleanly furnishes 1,1′‐((1 ‐pyrrole‐2,5‐diyl)bis(methylene))bis(1,1‐di‐ ‐butyl‐ N ‐(trimethylsilyl)‐λ 5 ‐phosphanimine) 1 ; (NPNPN)H, NPNPN=C NSiMe in excellent yield. Pyrrole is easily deprotonated by alkali metal amides, [MN(SiMe ] (M=Li, Na, K...