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Esters carbons

Reaction that can be carried out by the oxidative coupling of radicals may also be initiated by irradiation with UV light. This procedure is especially useful if the educt contains oleflnic double bonds since they are vulnerable to the oxidants used in the usual phenol coupling reactions. Photochemically excited benzene derivatives may even attack ester carbon atoms which is generally not observed with phenol radicals (I. Ninoraiya, 1973 N.C. Yang, 1966). [Pg.295]

TT-Aliylpalladium chloride reacts with a soft carbon nucleophile such as mal-onate and acetoacetate in DMSO as a coordinating solvent, and facile carbon-carbon bond formation takes place[l2,265], This reaction constitutes the basis of both stoichiometric and catalytic 7r-allylpalladium chemistry. Depending on the way in which 7r-allylpalladium complexes are prepared, the reaction becomes stoichiometric or catalytic. Preparation of the 7r-allylpalladium complexes 298 by the oxidative addition of Pd(0) to various allylic compounds (esters, carbonates etc.), and their reactions with nucleophiles, are catalytic, because Pd(0) is regenerated after the reaction with the nucleophile, and reacts again with allylic compounds. These catalytic reactions are treated in Chapter 4, Section 2. On the other hand, the preparation of the 7r-allyl complexes 299 from alkenes requires Pd(II) salts. The subsequent reaction with the nucleophile forms Pd(0). The whole process consumes Pd(ll), and ends as a stoichiometric process, because the in situ reoxidation of Pd(0) is hardly attainable. These stoichiometric reactions are treated in this section. [Pg.61]

Pos twe-Tone Photoresists. The ester, carbonate, and ketal acidolysis reactions which form the basis of most positive tone CA resists are thought to proceed under specific acid catalysis (62). In this mechanism, illustrated in Figure 22 for the hydrolysis of tert-huty acetate (type A l) (63), the first step involves a rapid equihbrium where the proton is transferred between the photogenerated acid and the acid-labile protecting group ... [Pg.126]

The reaction of phosgene (carbonic dichloride [75-44-5]) with alcohols gives two classes of compounds, carbonic esters and carbonochloridic esters, commonly referred to as carbonates and chloroformates. The carbonic acid esters (carbonates), R0C(0)0R, are the diesters of carbonic acid [463-79-6]. The carbonochloridic esters, also referred to as chloroformates or chlorocarbonates, C1C(0)0R, are esters of hypothetical chloroformic acid [463-73-0] CICOOH. [Pg.37]

With Alcohols, Ethers, and Esters. Carbon monoxide reacts with alcohols, ethers, and esters to give carboxyHc acids. The reaction yielding carboxyHc acids is general for alkyl (53) and aryl alcohols (54). It is cataly2ed by rhodium or cobalt in the presence of iodide and provides the basis for a commercial process to acetic acid. [Pg.52]

Nearly all of the polymers produced by step-growth polymerization contain heteroatoms and/or aromatic rings in the backbone. One exception is polymers produced from acyclic diene metathesis (ADMET) polymerization.22 Hydrocarbon polymers with carbon-carbon double bonds are readily produced using ADMET polymerization techniques. Polyesters, polycarbonates, polyamides, and polyurethanes can be produced from aliphatic monomers with appropriate functional groups (Fig. 1.1). In these aliphatic polymers, the concentration of the linking groups (ester, carbonate, amide, or urethane) in the backbone greatly influences the physical properties. [Pg.4]

Lipase CA catalyzed the polymerization of cyclic dicarbonates, cyclobis (hexamethylene carbonate) and cyclobis(diethylene glycol carbonate) to give the corresponding polycarbonates [105]. The enzymatic copolymerization of cyclobis(diethylene glycol carbonate) with DDL produced a random ester-carbonate copolymer. As to enzymatic synthesis of polycarbonates, reported were polycondensations of 1,3-propanediol divinyl dicarbonate with 1,3-propanediol [110], and of diphenyl carbonate with bisphenol-A [111]. [Pg.255]

Esters Carbon, hydrogen, single bonds, and at least one -COOC in the molecule (may include double and triple bonds and other structures) p 1 H rr H-C-C H 1 1 H O-C-H H Methyl ethanoate... [Pg.100]

Our interpretation of these phenomena is as follows the ester styryl perchlorate is not stable alone in solution, but this ester and its oligomeric homologues do exist in the presence of excess styrene, consequently the styrene must stabilise the ester. Presumably it does this by being co-ordinated (probably to the oxygen atoms) and thus reduces the polarity of the ester carbon-oxygen bond. It is not known yet whether any other compounds can exert the same effect. [Pg.663]

While ester, carbonate, carbamate and anilide hydrolyses have been catalysed effectively by antibodies, the difficult tasks of hydrolysis of an aliphatic amide or a urea remain largely unsolved. Much of this problem hinges on the fact that breakdown of a TF is the rate-determining step, as established by much... [Pg.299]

The meso-ionic 1,3-oxazol-S-ones show an incredible array of cycloaddition reactions. Reference has already been made to the cycloaddition reactions of the derivative 50, which are interpreted as involving cycloaddition to the valence tautomer 51. In addition, an extremely comprehensive study of the 1,3-dipolar cycloaddition reactions of meso-ionic l,3-oxazol-5-ones (66) has been undertaken by Huisgen and his co-workers. The 1,3-dipolarophiles that have been examined include alkenes, alkynes, aldehydes, a-keto esters, a-diketones, thiobenzophenone, thiono esters, carbon oxysulfide, carbon disulfide, nitriles, nitro-, nitroso-, and azo-compounds, and cyclopropane and cyclobutene derivatives. In these reactions the l,3-oxazol-5-ones (66)... [Pg.18]

The reactivity of phosphorus ylides towards carbonyl compounds such as ketones, esters, carbonates and amides has also been explored13. The mechanism shown in... [Pg.306]

Compositions of the ABS type may be mixed with other polymers. Suitable blend partners can be selected from poly(carbonate)s (PC)s, poly(ester)s, poly(ester carbonate)s and poly(amide)s (PA)s. Some especially preferred types, of these compounds and an overview of how to produced these types have been described (16). [Pg.221]

Organic acid esters carbonates (e.g. ethyl carbonate), formates, acetates (e.g. ethyl acetate, butyl acetate, amyl acetate), propionates, etc., oxalates (e.g. ethyl oxalate), maleates, phtha-lates (e.g. butyl phthalate) carbamates and phenylcarbamates (e.g. ethyl phenylcarbamate). [Pg.258]

Methyl Ester Carbons Saturates Monoenes Branched ... [Pg.190]

Methyl Ester Carbons Weight Percent of Total Methyl Esters ... [Pg.191]

Amino groups react very easily with aldehydes or ketones, and with aldehydes in the presence of amines, they can be acylated by the usual acylating agents, and they react with amidacetals, Vilsmeier reagents and nitroso compounds (Scheme 12). As mentioned earlier, alkylation leads mainly to AT(2)-alkylated products. The hydrazino group reacts in the same way as the amino group with aldehydes or ketones, with acyl chlorides or carboxylic anhydrides, with sulfonyl chlorides, ortho esters, carbon disulfide and with nitrous acid. The last three reactions have mainly been used for the synthesis of condensed 1,2,4-triazines. [Pg.418]


See other pages where Esters carbons is mentioned: [Pg.18]    [Pg.162]    [Pg.144]    [Pg.262]    [Pg.128]    [Pg.270]    [Pg.271]    [Pg.425]    [Pg.750]    [Pg.610]    [Pg.86]    [Pg.87]    [Pg.89]    [Pg.91]    [Pg.247]    [Pg.513]    [Pg.262]    [Pg.147]    [Pg.624]    [Pg.137]    [Pg.161]    [Pg.117]    [Pg.220]    [Pg.40]    [Pg.318]    [Pg.125]    [Pg.903]    [Pg.46]    [Pg.358]    [Pg.86]    [Pg.42]   
See also in sourсe #XX -- [ Pg.161 , Pg.171 , Pg.172 , Pg.178 ]




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Carbonate esters

Carbonic esters

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