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Acetic methoxy

Nucleophilic attack. Current literature underestimates the importance of nucleophilic attack as a mechanism for the catalytic decomposition of phosphines, especially with nucleophiles such as acetate, methoxy, hydroxy and hydride (Figure 2.37). For examples of nucleophilic attack at co-ordinated phosphorus see references [36],... [Pg.53]

Mercuric acetate methoxy ethyl mercury acetate, phenyl mercury acetate... [Pg.1041]

Kinetics of the formation of 2-methoxycarbonyl-5,7-dinitrobenzothiazole-3-oxide by cyclization of S-(2,4,6-trinitrophenyl)mercap(oacc(a(c in acetate, methoxy-acetate, or IV-methylmorfoline buffers has been studied [601], In the first two buffers the cyclization follows two reaction pathways, which differ in the order of reaction steps, with the proton splitting off from the C-H group being the rate-limiting step in either pathway (Scheme 2.110). [Pg.128]

ISOALLOXAZINES Oxygen. isocouMARiNs Dimethylsulfoxonium methy-lide. Thallium(III) trifluoroacetate. KETENE-0,S-ACETALS Methoxy(phenylthio)-trimethylsilylmethyllithium. [Pg.666]

Thin with xylene, butyl acetate, methoxy propyl acetate 60 20 20 to 18 s DIN 4 cup. Application solids 53%. Pot life 8h. Dust-free time 30 min, tack-free time 130 min. [Pg.236]

Mix parts A and B. Thin to spray viscosity with 9 3 1 butyl acetate methoxy propyl acetate ethyl acetate. [Pg.306]

Methoxy-1-methylethyl acetate. See Propylene glycol methyl ether acetate Methoxy PEG-6... [Pg.2206]

The oxidation of the cyclic enol ether 93 in MeOH affords the methyl ester 95 by hydrolysis of the ketene acetal 94 formed initially by regioselective attack of the methoxy group at the anomeric carbon, rather than the a-alkoxy ketone[35]. Similarly, the double bond of the furan part in khellin (96) is converted ino the ester 98 via the ketene acetal 97[l23],... [Pg.34]

Diacetoxylation of various conjugated dienes including cyclic dienes has been extensively studied. 1,3-Cyclohexadiene was converted into a mixture of isomeric l,4-diacetoxy-2-cyclohexenes of unknown stereochemistry[303]. The stereoselective Pd-catalyzed 1,4-diacetoxylation of dienes is carried out in AcOH in the presence of LiOAc and /or LiCI and beiizoquinone[304.305]. In the presence of acetate ion and in the absence of chloride ion, /rau.v-diacetox-ylation occurs, whereas addition of a catalytic amount of LiCl changes the stereochemistry to cis addition. The coordination of a chloride ion to Pd makes the cis migration of the acetate from Pd impossible. From 1,3-cyclohexadiene, trans- and ci j-l,4-diacetoxy-2-cyclohexenes (346 and 347) can be prepared stereoselectively. For the 6-substituted 1,3-cycloheptadiene 348, a high diaster-eoselectivity is observed. The stereoselective cij-diacetoxylation of 5-carbo-methoxy-1,3-cyclohexadiene (349) has been applied to the synthesis of dl-shikimic acid (350). [Pg.68]

The reaction of 2,3-butadienyl acetate (843) with soft carbon nucleophiles such as dimethyl malonate gives dimethyl 2,3-butadienylmalonate (844)[520]. On the other hand, the reaction of the 2,3-butadienyl phosphate 845 with hard carbon nucleophiles such as Mg and Zn reagents affords the 2-allcyl-1,3-butadiene 846[520,521]. The 3-methoxy-1,3-butadiene 848 is obtained by the reaction of the 2-methoxy-2,3-butadienyl carbonate 847 with organozinc reagent. [Pg.405]

The prefix thioxo- is used for naming =S in a thioketone. Sulfur analogs of acetals are named as alkylthio- or arylthio-. For example, CH3CH(SCH3)OCH3 is l-methoxy-l-(methylthio)ethane. Prefix forms for -carbothioic acids are hydroxy(thiocarbonyl)- when referring to the O-substituted acid and mercapto(carbonyl)- for the S-substituted acid. [Pg.38]

Chemical Structure and Properties. Homopolymer consists exclusively of repeating oxymethylene units. The copolymer contains alkyhdene units (eg, ethyUdene —CH2—CH2—) randomly distributed along the chain. A variety of end groups may be present in the polymers. Both homopolymer and copolymer may have alkoxy, especially methoxy (CH3 O—), or formate (HCOO—) end groups. Copolymer made with ethylene oxide has 2-hydroxyethoxy end groups. Homopolymer generally has acetate end groups. [Pg.57]

Diuretics. Chlomieodrin [62-37-3] (methoxy(urea)propylmercuric chloride) (8), is prepared ia the same sort of reaction used for chloromethoxypropylmercuric acetate. Ahyl urea is used instead of aHyl chloride, together with methanol and mercuric acetate. The product, after dilution with water and neutralization, is precipitated with sodium chloride ... [Pg.116]

Unsaturation value can be determined by the reaction of the akyl or propenyl end group with mercuric acetate ia a methanolic solution to give acetoxymercuric methoxy compounds and acetic acid (ASTM D4671-87). The amount of acetic acid released ia this equimolar reaction is determined by titration with standard alcohoHc potassium hydroxide. Sodium bromide is normally added to convert the iasoluble mercuric oxide (a titration iaterference) to mercuric bromide. The value is usually expressed as meg KOH/g polyol which can be converted to OH No. units usiag multiplication by 56.1 or to percentage of vinyl usiag multiplication by 2.7. [Pg.352]

Fig. 8. Basic chemistry of acetoxy-based RTV sihcones. The reactions for curing methoxy-based RTV sihcones are the same in that case, the methoxy group (OCH ) replaces acetoxy (OOCCH ), and methanol (CH OH), rather than acetic acid (CH COOH), is formed. Fig. 8. Basic chemistry of acetoxy-based RTV sihcones. The reactions for curing methoxy-based RTV sihcones are the same in that case, the methoxy group (OCH ) replaces acetoxy (OOCCH ), and methanol (CH OH), rather than acetic acid (CH COOH), is formed.
Methylation of avermectins B and B2 leads to the corresponding derivatives of the A series (49). A procedure involving the oxidation of the 5-methoxy group with mercuric acetate and NaBH reduction of the 5-keto-intermediate allows the conversion of the A to the B components (50). The 23-hydroxy group of the "2" components, after selective protection of the other secondary hydroxy groups, is converted to a thionocarbonate, which can be elirninated to give the 22,23-double bond of the "1" components alternatively it can be reduced with tributyltin hydride to the 22,23-dihydro derivatives (= ivermectins) (51). [Pg.284]

The principal coloring matter in turmeric and its oleoresin is curcumin [458-37-7] (l,6-heptadiene-3,5-dione, l,7-bis[4-hydroxy-3-methoxy-phenyl] (45), an orange-yeUow, crystalline powder, insoluble in water and ether but soluble in ethanol and glacial acetic acid. It has a reported melting point of 180-183°C. [Pg.451]

Methoxypyridazine 1-oxide reacts with methyl /3-aminocrotonate in the presence of benzoyl chloride to give a-(6-methoxy-3-pyridazinyl) /3-aminocrotonate (112) which can be converted by mild hydrolysis into the corresponding acetate (113 Scheme 34) <78JHC1425). [Pg.24]


See other pages where Acetic methoxy is mentioned: [Pg.19]    [Pg.586]    [Pg.191]    [Pg.45]    [Pg.19]    [Pg.586]    [Pg.191]    [Pg.45]    [Pg.32]    [Pg.101]    [Pg.127]    [Pg.291]    [Pg.615]    [Pg.546]    [Pg.325]    [Pg.524]    [Pg.436]    [Pg.444]    [Pg.469]    [Pg.395]    [Pg.18]    [Pg.19]    [Pg.24]    [Pg.32]    [Pg.37]   
See also in sourсe #XX -- [ Pg.157 , Pg.158 ]




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2- Methyl-5-methoxy-3-indole acetic acid

2- ethanol 3-Methoxy ethyl acetate

2-Methoxy-4-propenyl Phenyl Acetate

2-Methyl-5-methoxy-3-indolyl acetic acid

3-Methoxy-4-ethoxyphenyl acetic acid

Acetic 4-methoxy-2-methylphenyl

Acetic acid, methoxy

Alkyl methoxy acetates

Ethyl methoxy acetate

Methoxy acetate

Methoxy acetate

Methoxy ethyl mercury acetate

Methoxy-3-cephem-4-carboxylic acid 94 ---acetate

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