Showing papers by "Richard F. Jordan published in 1998"
205 citations
TL;DR: The synthesis, structures, and reactivity of cationic aluminum complexes containing the N,N'-diisopropylaminotroponiminate ligand ((i)Pr(2)-ATI)Al(R)(L)], which has been characterized by X-ray crystallography, are described.
Abstract: The synthesis, structures, and reactivity of cationic aluminum complexes containing the N,N‘-diisopropylaminotroponiminate ligand (iPr2-ATI-) are described. The reaction of (iPr2-ATI)AlR2 (1a−e,g,h; R = H (a), Me (b), Et (c), Pr (d), iBu (e), Cy (g), CH2Ph (h)) with [Ph3C][B(C6F5)4] yields (iPr2-ATI)AlR+ species whose fate depends on the properties of the R ligand. 1a and 1b react with 0.5 equiv of [Ph3C][B(C6F5)4] to produce dinuclear monocationic complexes [{(iPr2-ATI)AlR}2(μ-R)][(C6F5)4] (2a,b). The cation of 2b contains two (iPr2-ATI)AlMe+ units linked by an almost linear Al−Me−Al bridge; 2a is presumed to have an analogous structure. 2b does not react further with [Ph3C][B(C6F5)4]. However, 1a reacts with 1 equiv of [Ph3C][B(C6F5)4] to afford (iPr2-ATI)Al(C6F5)(μ-H)2B(C6F5)2 (3) and other products, presumably via C6F5- transfer and ligand redistribution of a [(iPr2-ATI)AlH][(C6F5)4] intermediate. 1c−e react with 1 equiv of [Ph3C][B(C6F5)4] to yield stable base-free [(iPr2-ATI)AlR][B(C6F5)4] complexes...
146 citations
TL;DR: In this article, the synthesis and structures of new aluminum complexes incorporating guanidinate ligands (R2NC(NR')2-) are described, and the reaction of iPrN=C=NiPr with LiNR2 reagents yields Li[R 2NC(NiPr)2] guanidine salts, which are reacted in situ with AlCl3 or AlMe2Cl to afford {R2nc(NiP)2}AlCl2 (1a, R = Me; 1b, r = Et; 1c, R=R
117 citations
TL;DR: In this paper, the synthesis and structures of aluminum complexes incorporating bulky thioamidate (RC(NR)S-), thioureido (R‘HNC(NR‘)S)-and amidinate (RC (NR)2-) ligands are described.
93 citations
TL;DR: In this paper, the synthesis and reactivity of out-of-plane (Me8taa)MX2 and (Me 8taa)-MX+ complexes (M= Zr, Hf, X= Cl, hydrocarbyl, NR2, OR) containing the dianionic tetraaza-macrocycle ligand octamethyldibenzotetraazaannulene (me8tAA2-) are described.
56 citations
TL;DR: The reaction of Cp*(η5-C2B9H11)TiMe (1, cp* = C5Me5) with CO (0.5−1 atm) in toluene (−78 to 23 °C) yields a 1:4 mixture of C p*( η5:η1-8-CHMeO-C 2B 9H10)Ti(NCMe).
34 citations
TL;DR: The behavior of (C2B9H11)M(NEt2)2(NHEt2] [M=Ti (1), Zr (2)] mono-dicarbollide complexes in olefin and styrene polymerisation has been investigated in this paper.
Abstract: The behavior of (C2B9H11)M(NEt2)2(NHEt2) [M=Ti (1), Zr (2)] mono-dicarbollide complexes in olefin and styrene polymerisation has been investigated. Compounds 1 and 2, when activated by MAO (Al/M=100 to 1000), polymerise ethylene with good activity. Surprisingly, 2 can also be activated with small amounts of triisobutylaluminum (TIBA, Al/Zr=3 to 40). The ethylene polymerisation activity of the 2/TIBA catalyst (50°C, 5 atm, toluene–chlorobenzene) is greater than that reported for the CpZrX3/MAO catalysts but lower by about one or two orders of magnitude than zirconocene–MAO systems (e.g. Cp2ZrCl2/MAO, rac-(ethylene-bis-1-idenyl)ZrCl2/MAO). The GPC (gel permeation chromatography) curve of the polyethylene sample obtained with 2/TIBA catalyst (50°C, 5 atm, toluene–chlorobenzene) is bimodal indicating that at least two species are active in this system and one is more active than the other. The 2/MAO system (50°C, 5 atm, toluene–chlorobenzene) slowly polymerises propylene to atactic polymer. Under the same experimental conditions 1-pentene does not polymerise at all. Compounds 1 and 2, activated with MAO, produce syndiotactic polystyrene (sPS) with very low activity. Attempts to copolymerise styrene with ethylene by the 1/MAO and 2/MAO systems afforded a mixture of the two homopolymers.
17 citations
Patent•
12 Mar 1998TL;DR: In this article, the authors proposed novel catalysts, processes of synthesizing the catalysts and olefin polymerization processes using them, and showed that these compounds behave similarly to Ziegler-Natta catalysts but effectively catalyze the polymerization of olefins in the absence of any transition metal.
Abstract: Disclosed are novel catalysts, processes of synthesizing the catalysts and olefin polymerization processes using the catalysts. The catalysts are cationic complexes comprising a Group 13 element and certain ligands. These compounds behave similarly to Ziegler-Natta catalysts but effectively catalyze the polymerization of olefins in the absence of any transition metal.
15 citations
TL;DR: The reaction of Li2SBI (SBI = Me2Si(1-indenyl)2) with 2 equiv of AlMe2Cl in Et2O, followed by treatment with THF, affords {AlMe2(THF)2SiMe2 (1), which is isolated as a ca. 1/1 mixture of rac and meso isomers, from which rac-1 is obtained by crystallization from toluene.
13 citations