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Arylation esters

Alkenylboranes (R2C=CHBZ2 Z — various groups) couple in high yields with vinylic, alkynyl, aryl, benzylic, and allylic halides in the presence of tetra-kis(triphenylphosphine)palladium, Pd(PPh3)4, and a base to give R C CHR. 9-Alkyl-9-BBN compounds (p. 1013) also couple with vinylic and aryl halides " as well as with a-halo ketones, nitriles, and esters.Aryl halides couple with ArB(IR2 ) species with a palladium catalyst. ... [Pg.541]

Trialkylboranes react rapidly and in high yields with a-halo ketones,a-halo esters, a-halo nitriles, and a-halo sulfonyl derivatives (sulfones, sulfonic esters, sulfonamides) in the presence of a base to give, respectively, alkylated ketones, esters, nitriles, and sulfonyl derivatives. Potassium tert-butoxide is often a suitable base, but potassium 2,6-di-tert-butylphenoxide at 0°C in THF gives better results in most cases, possibly because the large bulk of the two tert-buXy groups prevents the base from coordinating with the R3B. The trialkylboranes are prepared by treatment of 3 mol of an alkene with 1 mol of BH3 (15-16). With appropriate boranes, the R group transferred to a-halo ketones, nitriles, and esters can be vinylic, or (for a-halo ketones and esters) aryl. " °... [Pg.560]

Recent notable improvements by Knochel and co-workers include iron-catalyzed cross-coupling reactions of various acid chlorides 148 with dialkylzinc reagents (Equation (24))324 as well as the iron-catalyzed arylation of aroyl cyanides 149 with Grignard reagents (Equation (25)).3 5 In the first case Knochel s reaction conditions tolerate ester groups on the organozinc compounds, while in the latter case ester, aryl alkyl ether, cyano, and chloro functionalities on the aromatic moieties are compatibles with the reaction conditions. [Pg.439]

A reaction which is related to hydroxy-de-diazoniations is the formation of aryl trifluoromethylsulfonic esters (aryl triflates, ArOSC CFs) which became widely used reagents because of their leaving-group properties. The classical method of synthesis by esterification of phenols with trifluoromethane-sulfonic anhydride or -sulfonyl halide is, however, not applicable for the preparation of aryl triflates bearing a (free)... [Pg.656]

Addition to linear 1,1-disubstituted allylic acetates is slower than addition to monosubstituted allylic esters. Additions to allylic trifluoroacetates or phosphates are faster than additions to allylic carbonates or acetates, and reactions of branched allylic esters are faster than additions to linear allylic esters. Aryl-, vinyl, alkynyl, and alkyl-substituted allylic esters readily undergo allylic substitution. Amines and stabilized enolates both react with these electrophiles in the presence of the catalyst generated from an iridium precursor and triphenylphosphite. [Pg.176]

Table 2 contains the characteristics of the amic ester-aryl ether copolymers including coblock type, composition, and intrinsic viscosity. Three series of copolymers were prepared in which the aryl ether phenylquinoxaline [44], aryl ether benzoxazole [47], or aryl ether ether ketone oligomers [57-59] were co-re-acted with various compositions of ODA and PMDA diethyl ester diacyl chloride samples (2a-k). The aryl ether compositions varied from approximately 20 to 50 wt% (denoted 2a-d) so as to vary the structure of the microphase-separated morphology of the copolymer. The composition of aryl ether coblock in the copolymers, as determined by NMR, was similar to that calculated from the charge of the aryl ether coblock (Table 2). The viscosity measurements, also shown in Table 2, were high and comparable to that of a high molecular weight poly(amic ethyl ester) homopolymer. In some cases, a chloroform solvent rinse was required to remove aryl ether homopolymer contamination. It should also be pointed out that both the powder and solution forms of the poly(amic ethyl ester) copolymers are stable and do not undergo transamidization reactions or viscosity loss with time, unlike their poly(amic acid) analogs. Table 2 contains the characteristics of the amic ester-aryl ether copolymers including coblock type, composition, and intrinsic viscosity. Three series of copolymers were prepared in which the aryl ether phenylquinoxaline [44], aryl ether benzoxazole [47], or aryl ether ether ketone oligomers [57-59] were co-re-acted with various compositions of ODA and PMDA diethyl ester diacyl chloride samples (2a-k). The aryl ether compositions varied from approximately 20 to 50 wt% (denoted 2a-d) so as to vary the structure of the microphase-separated morphology of the copolymer. The composition of aryl ether coblock in the copolymers, as determined by NMR, was similar to that calculated from the charge of the aryl ether coblock (Table 2). The viscosity measurements, also shown in Table 2, were high and comparable to that of a high molecular weight poly(amic ethyl ester) homopolymer. In some cases, a chloroform solvent rinse was required to remove aryl ether homopolymer contamination. It should also be pointed out that both the powder and solution forms of the poly(amic ethyl ester) copolymers are stable and do not undergo transamidization reactions or viscosity loss with time, unlike their poly(amic acid) analogs.
Table 2. Characteristics of amic ester-aryl ether block copolymers... Table 2. Characteristics of amic ester-aryl ether block copolymers...
Prior to imide formation, the imide-aryl ether ketimine copolymers were converted to the imide-aryl ether ketone analogue by hydrolysis of the ketimine moiety with para-toluene sulfonic acid hydrate (PTS) according to a literature procedure [51,52,57-59]. The copolymers were dissolved in NMP and heated to 50 °C and subjected to excess PTS for 8 h. The reaction mixtures were isolated in excess water and then rinsed with methanol and dried in a vacuum oven to afford the amic ester-aryl ether ether ketone copolymer, 2e (Scheme 8.)... [Pg.75]

Table 7. Imidization rates of various monoalkyl ester aryl phthalamides in W-methyl pyrollidone... Table 7. Imidization rates of various monoalkyl ester aryl phthalamides in W-methyl pyrollidone...
With appropriate boranes, the R group transferred to a-halo ketones, nitriles, and esters can be vinylic,1555 or (for a-halo ketones and esters) aryl.1556... [Pg.480]

A somewhat different type of coupling is observed when salts of p-keto esters, aryl-acetonitriles ArCH2CN, and other compounds of the form ZCH2Z are treated with an... [Pg.1203]

Chiralcel OJ Cellulose tris(4-methyl benzoate) Aryl methyl esters, aryl methoxy esters ... [Pg.50]

Four main types of antioxidants are commonly used in polypropylene stabilizer systems although many other types of chemical compounds have been suggested. These types include hindered phenolics, thiodi-propionate esters, aryl phosphites, and ultraviolet absorbers such as the hydroxybenzophenones and benzotriazoles. Other chemicals which have been reported include aromatic amines such as p-phenylenediamine, hydrocarbon borates, aminophenols, Zn and other metal dithiocarbamates, thiophosphates, and thiophosphites, mercaptals, chromium salt complexes, tin-sulfur compounds, triazoles, silicone polymers, carbon black, nickel phenolates, thiurams, oxamides, metal stearates, Cu, Zn, Cd, and Pb salts of benzimidazoles, succinic acid anhydride, and others. The polymeric phenolic phosphites described here are another type. [Pg.218]

The traditional scope for this reaction involved coupling alkenyl or aryl iodides or bromides with aryl, alkenyl, or alkynylzinc halides. However, recent modifications have allowed the scope to be extended to include additional electrophiles see Electrophile) such as aryl and vinyl chlorides, sulfonate esters, aryl ethers, and substrates with... [Pg.5646]

A wide variety of substituents are tolerated. The group R can be alkyl, halogen, alkoxy, -amido, azi-domethyl, ester, aryl, aryloxy and aryloyl, and at least one ortho substituent is permissible with no loss in yield. TTie aromatic ring can also be 2-naphthyl, 9,10-dihydro-2-phenanthryl, 3-pyridyl, thiophen-2-yl or pyrrol-3-yl. The group R can be hydrogen, yl, acyl or acetic acid. Beyond Ae antiinflammatory targets, successful reaction substrates include the methyl ketones of a binaphthyl crown ether, a morphinane and a polyaromatic hydrocarbon. The preparation of ibuprofen methyl ester (38) is shown in equation (37) as a typical example. ... [Pg.829]

Boronic ester Aryl halide Product Yield, %... [Pg.59]

The two enzymes differ in specificity toward some substrates while behaving similarly toward others. The serum enzyme acts on benzoylcholine but cannot hydrolyze acetyl-p-methylcholine the red cell enzyme acts on the latter but not on the former. The red cell enzyme splits only choline esters aryl or alkyl esters are not attacked. The red cell enzyme is inhibited by its substrate, acetylcholine, if present at about 10 mol/L the serum enzyme is not inhibited by this substrate. [Pg.614]


See other pages where Arylation esters is mentioned: [Pg.479]    [Pg.479]    [Pg.479]    [Pg.483]    [Pg.227]    [Pg.73]    [Pg.618]    [Pg.117]    [Pg.79]    [Pg.1106]    [Pg.2376]    [Pg.354]    [Pg.66]    [Pg.58]    [Pg.16]    [Pg.47]    [Pg.1106]    [Pg.829]    [Pg.177]    [Pg.313]    [Pg.644]    [Pg.902]    [Pg.645]    [Pg.66]    [Pg.1313]   
See also in sourсe #XX -- [ Pg.466 ]




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1- aryl ester naphthalene

1-aryl-l-alken-3-yne 1-borio-2-halo- 1-alkene carboxylate ester

2- -2,3-alkadienoate ester alkanal aryl diester

2-Aryl-3-methylbutyric acid esters

2-alkenoate ester sulfone alkyl aryl

2-aryl-4-oxazolecarboxylic acid esters

2-aryl-5-methoxy-4-oxazolecarboxylic acid methyl esters

4-alkenoate aryl ester 1 -lithio-1 -alkene

5-aryl -4-oxazolecarboxylic acid methyl esters

Alkyl and Aryl Esters of Arenesulfonic Acids

Alkylcarbamic acid aryl esters

Alkylsulfonic acid aryl esters

Arenesulfonic aryl esters

Aromatic compounds from aryl esters

Aryl boronic esters

Aryl carboxylic esters, formation

Aryl derivs. (s. a. Arenes esters

Aryl diethyl phosphate esters

Aryl enol esters

Aryl enol esters bromide

Aryl esters

Aryl esters

Aryl esters Fries rearrangement

Aryl esters in peptide bond formation

Aryl esters irradiation

Aryl esters preparation

Aryl esters singlet-state radical pairs

Aryl esters, oxidation

Aryl halides with carboxylic esters

Aryl ketones and esters

Aryl with aryboronic esters

Aryl-ester hydrolase

Aryl-ester polymers, performance

Arylacetic acid esters aryl methyl ketones

Arylation acrylic esters

Arylation cyanoacetate esters

Arylation of Esters

Arylations of Esters

Arylations of Malonates and a-Cyano Esters

Arylboronic acid esters arylation

Benzoic acids, aryl esters

Benzoic acids, aryl esters hydrolysis

Biaryl triflate aryl ester

Calix aryl esters

Carboxylic acid aryl ester

Carboxylic esters arylation

Carboxylic esters, aryl

Carboxylic esters, aryl carbonylation

Carboxylic esters, aryl compounds

Carboxylic esters, aryl methyl, cleavage

Chloroformic acid esters aryl chloroformates

Esters aryl substitution

Esters aryl, aminolysis

Esters arylation carboxylic acid

Esters arylation derivatives

Esters arylation tetrahydroisoquinoline

Esters from aryl halides

Esters from aryl nitro compounds

Esters hindered aryl

Glyoxalic acids, aryl-, esters

Haloarene triflate aryl ester

Halogenothioformic acid aryl esters

Hydrolysis aryl esters, ortho

Lewis acids with aryl esters

Malonic acid aryl esters

Malonic acid aryl esters cyclic

Malonic ester synthesis arylation

Malonic esters, aryl methylene

Methanesulfonic acid aryl esters

Nucleophilic Cleavage of Aryl Esters

Palladium-catalyzed Suzuki-Miyaura Cross-coupling Reactions of Functionalized Aryl and Heteroaryl Boronic Esters

Phenols carboxylic acid aryl ester

Phosphate esters aryl, reduction

Photo-Fries Reactions of Aryl Esters

Photo-Fries rearrangement aryl ester

Polymers aryl esters, photo-reactions

Relative Rate Information from Irradiation of Aryl Esters in Which Acyl Radicals Do Not Decarbonylate Rapidly

Stereoselective arylation, allylic esters

Thiocarbamic 0-aryl esters

Triflate aryl ester phenol

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