Triphenylphosphine-copper bromide

Lithium wire (3.2 mm diam.), carbon tetrachloride, triphenylphosphine, MgBrEtaO, copper bromide-dimethyl sulfide complex, hexanoyl chloride, methyllithium, p-toluenesulfonic acid monohydrate, potassium hydride, and 18-crown-6 were purchased from Aldrich Chemical Company, Inc. and used without further purification. 

The position of copper(I) salts as quite soft Lewis acids has resulted in a significant number of publications where soft phosphorus- and sulfur-containing ligands have been used and shown to enhance the catalytic process in CuAAC reactions. A variety of phosphorus-containing ligands has been used to produce significant rate enhancements or improved efficiency in CuAAC reactions. Examples include the use of triphenylphosphine-copper(I) bromide [137] (e.g., in the synthesis of dendrimers [138]), phosphoramidites [139], and bis(triphenylphosphine)-copper(I) carboxylates [140]. In addition, triethylphosphite-copper(I) iodide complexes have been used in sugar chemistry [141]. 

Tetrakis(triphenylphosphine)palla-dium(0)-Zinc, 346 Titanium(IV) chloride-Zinc, 310 Titanium(III) chloride-Zinc / copper couple, 303 Zinc, 298, 346, 348 Zinc amalgam, 347 Zinc borohydride, 167 Zinc bromide, 349... 

A round-bottom flask was charged with a mixture of 2,6-dimethylphenyl trifluoromethanesulfonate (127.1 mg, 0.5 mmol), anhydrous lithium chloride (4 mmol), copper(I) bromide (0.2 mmol), and dichlorobis(triphenylphosphine)-palladium(II) (10-20 mol %) suspended in DMF (2.5 cm ). 2-Methoxyphenyl-tributyltin (1-1.5 mmol) was added to the mixture in two portions, i.e., at the beginning of the reaction and at half completion. A crystal of 2,6-bis(l,l-dime-thylethyl)-4-methylphenol (BHT) was added as an inhibitor of radical processes, and the mixture was then heated to reflux, under argon, during 8 - 24 h. Water and Et20 (25 cm ) was added, and the organic phase was washed subsequently with hydrochloric acid solution (1.5 mol dm , 6 x 20 cm ), a saturated solution of potassium fluoride (5 x 20 cm ), and finally dried over anhydrous sodium sulfate. Evaporation to dryness furnished a residue and that was suspended in ethyl acetate and the insoluble material was filtered off. The filtrate was... 

A mixture of 6-bromo-4-(tri luoromethanesulfonyloxy)-5,8-dimethoxy-quinoline (1.35 g, 3.25 mmol), trimethyl[2-[(l,l-dimethylethoxycarbonyl)-amino]phenyl]tin (1.68 g, 4.70 mmol), lithium chloride (330 mg, 7.80 mmol), copper(I) bromide (25 mg, 0.17 mmol), and tetrakis(triphenylphosphine)palla-dium (0) (180 mg, 0.16 mmol) in dioxane (60 cm ) was heated at 90 °C for 60 h. After being cooled to rt, the mixture was partitioned between EtOAc and a 5 % aqueous ethylenediamine solution to remove any copper species, completely. After the usual work up, the residue was chromatographed (1.5 1 hexanes -EtOAc) to yield the title compound as a white solid (952 mg, 64%, several other fractions contained the title compound contaminated with 6-bromo-5,8-di-methoxy-4-methylquinoline) mp 166-168 °C. 

OXIMES AND SEMICARBAZONES Ceric ammonium nitrate. CLEMMENSEN REDUCTION Zinc dust. COMPLEX OF BENZYNE. Nickel carbonyl. n-COMPLEXES Diiron nonacarbonyl. CONDENSING AGENT Calcium carbide. CONJUGATE ADDITION Dimethylcop-perlithium. Nickel carbonyl. Tetrakisjiodo-(tri-ff-butylphosphine)copper(I)]. CONVERSION OF PHENOLS TO ARYL BROMIDES Triphenylphosphine dibromide. 

ALKENES Allyl dimethyldithiocarbamate. Bis(t -cyclopentadienyl)niobium trihydride. Cyanogen bromide. Di-n-butylcopperlithium. a,o-Dichloromethyl methyl ether. 2,3-Dimethyl-2-butylborane. N,N-Dimethyl dichlorophosphoramide. Diphenyl diselenide. Di-n-propylcopperlithium. Ferric chloride. Grignard reagents. Iodine. Lithium phenylethynolate. Lithium 2,2,6,6-tetramethylpiperidide. Methyl iodide. o-Nitro-phenyl selenocyanate. Propargyl bromide. rra s-l-Propenyllithium. Selenium. Tetrakis(triphenylphosphine)palladium. Titanium(IH) chloride. Titanium trichloride-Lithium aluminum hydride. p-Toluenesulfonylhydrazine. Triphenylphosphine. Vinyl-copper reagents. Vinyllithium. Zinc. 

A flask equipped with a heavy-walled side-arm was charged with polymer-supported aryl bromide (1.0 equiv.), bis(dibenzylideneacetone)palladium(0) (22 mequiv.), triphenylphosphine (110 mequiv.), and copper(I) iodide (22 mequiv.). The flask was evacuated and back-filled with dry nitrogen three times, a degassed mixture (5.7 mL/g of polymer) of triethylamine (2 parts) and A(A/-diemthylformamide (1 part) was added, trimethylsilylacetylene (2.0 equiv.) was added, the flask was sealed, and the suspension was stirred at 75 °C for 48 h. The polymer was transferred to a tared fritted filter using MeOH, washed sequentially (ca. 30 mL/g of polymer) with MeOH, DMF, CH2CI2, MeOH, a solution of sodium diethyldithiocarbamate (377 mg) and diisopropylethylamine (0.33 mL) in DMF (33 mL), DMF, CH2CI2 and MeOH, and dried in vacuo. 

It is well known that alk-2-ynones can be prepared from a copper(i) alkyne and an acyl halide. Now the troublesome metallation step can be avoided by direct reaction of the terminal alkyne with the acyl chloride in triethylamine containing copper(l) iodide and bis(triphenylphosphine)palladium(ii) chloride as catalysts. Cyanohydrins and propargyl bromides form alkynyl ethers which rearrange on treatment with lithium di-isopropylamide to form ar-allenic ketones (Scheme 59). ... 

Subsequently, compound 91 was elaborated to primary alcohol 92 with the H-ring functionality in a similar manner to the Sasaki synthesis (Scheme 11). For the introduction of the triene side chain, a simple and practical method for the stereoselective synthesis of (Z)-vinyl iodide, which is expected to be more reactive than the bromide counterpart, was developed [105]. Thus, PCC oxidation of alcohol 92 followed by treatment of the resultant aldehyde with tetraiodomethane and triphenylphosphine gave diiodoalkene 93. Reduction of 93 with the zinc-copper couple in the presence of acetic acid provided (Z)-vinyl iodide 94 in high yield. Since deprotection of the fully protected... 

We have applied cross-coupling reactions of alkynes and aryl bromides to prepare the structurally well-defined polybinaphthyl crown ethers. A racemic binaphthyl crown ether monomer roc-75 [18,62] is polymerized with roc-33 in the presence of tetrakis(triphenylphosphine) palladium(O) and copper iodide to generate a polybinaphthyl crown ether 76 (Scheme 32). This polymer is soluble in organic solvents and has been characterized by various spectroscopic methods. GPC analysis shows that 76 has a molecular weight of 30,000 and M = 12,000 (PDI = 2.4). The UV spectrum of the polymer shows the maximum absorptions - max = 246, 300, and 354 nm. 

Trimethylsilylacetylene couples smoothly with aryl iodides in the presence of catalytic amounts of bis(triphenylphosphine)palladium dichloride and copper(l) iodide to give, following deprotection, ethynylarenes (e.g. Scheme 110). Aryl bromides react only when they are suitably activated by electron-withdrawing... 

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