Acetylacetone alkylation

Substances that form carbanions, such as nitro compounds, hydrocyanic acid, malonic acid, or acetylacetone, react with vinyl ethers in the presence of water, replacing the alkyl group under mild conditions (245). 

Dicyclopentadiene is also polymerized with tungsten-based catalysts. Because the polymerization reaction produces heavily cross-Unked resins, the polymers are manufactured in a reaction injection mol ding (RIM) process, in which all catalyst components and resin modifiers are slurried in two batches of the monomer. The first batch contains the catalyst (a mixture of WCl and WOCl, nonylphenol, acetylacetone, additives, and fillers the second batch contains the co-catalyst (a combination of an alkyl aluminum compound and a Lewis base such as ether), antioxidants, and elastomeric fillers (qv) for better moldabihty (50). Mixing two Uquids in a mold results in a rapid polymerization reaction. Its rate is controlled by the ratio between the co-catalyst and the Lewis base. Depending on the catalyst composition, solidification time of the reaction mixture can vary from two seconds to an hour. Similar catalyst systems are used for polymerization of norbomene and for norbomene copolymerization with ethyhdenenorbomene. 

Vinylogous amides, which have an enamine function in conjugation with a carbonyl group, constitute tridentate systems and thus open the possibility of alkylation on carbon, nitrogen, or oxygen. It has been found that the pyrrolidine enamine of acetylacetone gives rise to a carbon mcthylation but an oxygen ethylation product 41). The alkylation of cyclic 1,3-diketone-derived enamines has been studied 41,283). O Alkylation was found in alcohol solvents and predominant C alkylation in nonprotonic solvents. 

Abbreviations acac, acetylacetonate Aik, alkyl AN, acetonitrile bpy, 2,2 -bipyridine Bu, butyl cod, 1,5- or 1,4-cyclooctadiene coe, cyclooctene cot, cyclooctatetraene Cp, cyclopentadienyl Cp, pentamethylcyclopenladienyl Cy, cyclohexyl dme, 1,2-dimethoxyethane dpe, bis(diphenyl-phosphino)ethane dppen, cis-l,2-bis(di[Atenylphosphino)ethylene dppm, bis(diphenylphosphino) methane dppp, l,3-bis(diphenylphosphino)propane eda,ethylenediamine Et,ethyl Hal,halide Hpz, pyrazole HPz, variously substituted pyrazoles Hpz, 3,5-dimethylpyrazole Me, methyl Mes, mesityl nbd, notboma-2,5-diene OBor, (lS)-endo-(-)-bomoxy Ph, phenyl phen, LlO-phenanthroline Pr, f opyl py, pyridine pz, pyrazolate Pz, variously substituted pyrazolates pz, 3,5-dimethylpyrazolate solv, solvent tfb, tetrafluorobenzo(5,6]bicyclo(2.2.2]octa-2,5,7-triene (tetrafluorobenzobanelene) THE, tetrahydrofuran tht, tetrahydrothicphene Tol, tolyl. 

Oxidadve cross-conphng reactions of alkylated derivatives of activated CH compounds, such as malonic esters, acetylacetone, cyanoacetates, and ceitain ketones, v/ithnitroalkanes promoted by silver nitrate or iodine lead to the formation of the nitroalkylated products. This is an alternative way of performing Spj l reactions using cr.-halo-nitroalkanes. 

Alkene complexes Alkynyl complexes Ammine complexes Aqueous chemistry Arsine complexes Auranofin Auride ion Aurophilicity Binary compounds Bond lengths acetylacetonate complex alkyls and aryls ammine complexes carboxylates cyanide complexes dialkyl sulphide complexes dithiocarbamates to gold... 

Alkene complexes Ammine complexes Aqueous chemistry Arsine complexes Binary compounds Bipyridyl complexes Bond lengths acetylacetonate alkene complexes alkyl and aryl complexes ammine complexes aqua ion... 

Titanium, tetrakis(trimethysilyl)oxy-, 3, 334 Titanium, tetranitrato-stereochemistry, 1,94 Titanium, triaquabis(oxalato)-structure, I, 78 Titanium, tris(acetylacetone)-structurc, 1,65 Titanium alkoxides oligomeric structure, 2,346 synthesis ammonia, 2, 338 Titanium chloride photographic developer, 6,99 Titanium complexes acetylacetone dinuclear, 2, 372 alkyl... 

Vanadium complexes, 3,453-569 acetylacetone exchange reactions, 2,380 alkyl peroxides... 

Zirconium complexes, 3, 363-440 acetylacetone, 2,372,377 ligand exchange reactions, 2, 381 rearrangement, 2, 383 alkyl... 

The acetylacetonates are stable in air and readily soluble in organic solvents. From this standpoint, they have the advantage over the alkyls and other alkoxides, which, with the exception of the iron alkoxides, are not as easily soluble. They can be readily synthesized in the laboratory. Many are used extensively as catalysts and are readily available. They are also used in CVD in the deposition of metals such as iridium, scandium and rhenium and of compounds, such as the yttrium-barium-copper oxide complexes, used as superconductors. 1 1 PI Commercially available acetyl-acetonates are shown in Table 4.2. 

Monoalkyltin(IV) compounds can be prepared under suitable conditions from tindl) compounds (44-46). Tin(II) bis(acetylacetonate) (acac) and related compounds react readily with a variety of alkyl bromides or iodides, to give the product RSn(acac)2X, e.g.,... 

Asymmetric AUylic Alkylation acetylacetonate Asymmetric Cross-Metathesis Acyclic Diene Metathesis allyl ether... 

The mechanism of formation of Pt particles by the or-ganometallic reduction route, however, was found to proceed differently, for example in the reductive stabilization of Pt nanoparticles produced by reacting Pt-acetylacetonate with excess trimethylaluminium. Here, derivates of aluminium alkyls act as both reducing agents and colloidal stabilizers. As was shown by a combination... 

Nickel acetylacetonate, Ni(acac)2, in the presence of a styrene derivative promotes coupling of primary alkyl iodides with organozinc reagents. The added styrene serves to stabilize the active catalytic species, and of the derivatives examined, m-trifluoromethylstyrene was the best.274... 

Palladium(II) acetate was found to be a good catalyst for such cyclopropanations with ethyl diazoacetate (Scheme 19) by analogy with the same transformation using diazomethane (see Sect. 2.1). The best yields were obtained with monosubstituted alkenes such as acrylic esters and methyl vinyl ketone (64-85 %), whereas they dropped to 10-30% for a,p-unsaturated carbonyl compounds bearing alkyl groups in a- or p-position such as ethyl crotonate, isophorone and methyl methacrylate 141). In none of these reactions was formation of carbene dimers observed. 7>ms-benzalaceto-phenone was cyclopropanated stereospecifically in about 50% yield PdCl2 and palladium(II) acetylacetonate were less efficient catalysts 34 >. Diazoketones may be used instead of diazoesters, as the cyclopropanation of acrylonitrile by diazoacenaph-thenone/Pd(OAc)2 (75 % yield) shows142). 

Examples of w-allylnickel-X compounds (X = anionic ligand) other than 77-allylnickel halides which have been used in combination with (alkyl)aluminum halides as olefin oligomerization catalysts are 7r-allyl-nickel acetylacetonate (11) (Section III), 7r-allylnickel aziridide (4, 56), and bis(7r-allyl)nickel (6) (59). In addition to ir-allylnickel halides, organo-nickel halides such as tritylnickel chloride (60, 61) and pentafluoro-phenylbis(triphenylphosphine)nickel bromide (62), or hydridonickel halides, e.g., trans-hydridobis(triisopropylphosphine)nickel chloride (12) (Section III), give active catalysts after activation with aluminum halides... 

This section deals with PES studies on alkyl-and chloro-tin complexes, with acetylacetonate and related ions as ligands53,137. Cauletti and coworkers53 investigated the following compounds ... 

In the course of a study on creation of a library of a great number of hetaryl ketones and related derivatives, Szewczyk et al. <2001AGE216> elaborated a ruthenium-catalyzed transformation of heterocycles with activated C-H bond by reaction with olefins and carbon monoxide. Thus, 253 gave 254, albeit in very poor yield. Synthetically, the more straightforward iron-catalyzed transformation was described by Fiirstner et al. <2002JA13856>. These authors reacted 255 with a Grignard reagent in the presence of Fe(acac)3 to afford the 7-alkyl-substituted derivative 256 in reasonable yield (acac = acetylacetonate). 

M = Metals of Groups 6-11 X= Halogen, Acetylacetonate n = 2-4. R = C1-C8-Alkyl, Particle sizes 1-12nm... 

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