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Addition butyl 2- acetate

Mercaptals, CH2CH(SR)2, are formed in a like manner by the addition of mercaptans. The formation of acetals by noncatalytic vapor-phase reactions of acetaldehyde and various alcohols at 35°C has been reported (67). Butadiene [106-99-0] can be made by the reaction of acetaldehyde and ethyl alcohol at temperatures above 300°C over a tantala—siUca catalyst (68). Aldol and crotonaldehyde are beheved to be intermediates. Butyl acetate [123-86-4] has been prepared by the catalytic reaction of acetaldehyde with 1-butanol [71-36-3] at 300°C (69). [Pg.51]

Some commercially important isobutyl derivatives include isobutyl acetate, employed as a replacement solvent for -butyl acetate zinc dialkyldithiophosphate (ZDPP) lube oil additives isobutyl acrylate [106-62-8] and methacrylate [97-86-9] monomers isobutylamines and amino resins (qv). [Pg.358]

The rate of solvent diffusion through the film depends not only on the temperature and the T of the film but also on the solvent stmcture and solvent-polymer iuteractions. The solvent molecules move through free-volume holes iu the films and the rate of movement is more rapid for small molecules than for large ones. Additionally, linear molecules may diffuse more rapidly because their cross-sectional area is smaller than that of branched-chain isomers. Eor example, although isobutyl acetate (IBAc) [105-46-4] has a higher relative evaporation rate than -butyl acetate... [Pg.334]

In spite of their intrinsic synthetic potential, addition reactions of metal enolates of non-stabilized esters, amides, and ketones to epoxides are not widely used in the synthesis of complex molecules. Following the seminal work of Danishefsky [64], who introduced the use of Et2AlCl as an efficient catalyst for the reaction, Taylor obtained valuable spiro lactones through the addition reaction of the lithium eno-late of tert-butyl acetate to spiro-epoxides, upon treatment of the corresponding y-... [Pg.295]

In another approach, a glucose-derived titanium enolate is used in order to accomplish stereoselective aldol additions. Again the chiral information lies in the metallic portion of the enolate. Thus, the lithiated /m-butyl acetate is transmetalated with chloro(cyclopentadienyl)bis(l,2 5,6-di-0-isopropylidene- -D-glucofuranos-3-0-yl)titanium (see Section I.3.4.2.2.I. and 1.3.4.2.2.2.). The titanium enolate 5 is reacted in situ with aldehydes to provide, after hydrolysis, /i-hydroxy-carboxylic acids with 90 95% ee and the chiral auxiliary reagent can be recovered76. [Pg.488]

The addition of lithium enolates to 2-alkoxyaldehydes occurs either in a completely non-stereoselective manner, or with moderate selectivity in favor of the product predicted by the Cram-Felkin-Anh model28 ( nonchelation control 3, see reference 28 for a survey of this type of addition to racemic aldehydes). Thus, a 1 1 mixture of the diastereomeric adducts results from the reaction of lithiated tert-butyl acetate and 2-benzyloxypropanal4,28. [Pg.563]

Esters and amides may be sulfinylated. Addition of a mixture of t-butyl acetate and sulfinate ester 19 to a THF-ether solution of magnesium diisopropylamide led to the formation of (R)-(+)-f-butyl p-toluenesulfinylacetate (49) in 90% yield (equation 14)7. t-Butyl propanoate and butanoate also underwent this sulfinylation to give 50 and 51 in yields of 68 and 45%, respectively83. The diastereomeric ratio was 1 1 for 50 and 3 7 for 51. These esters may also be obtained by alkylation of 49. Similarly, treatment of a-lithio-A, A -dimethylacetamide with sulfinate ester 19 gave (R)-( + )-N, Ar-dimethyl-p-toluene-sulfinylacetamide (52) (equation 15)84. [Pg.67]

In the presence of a strong base, the ot carbon of a carboxylic ester can condense with the carbonyl carbon of an aldehyde or ketone to give a P-hydroxy ester, which may or may not be dehydrated to the a,P-unsaturated ester. This reaction is sometimes called the Claisen reaction,an unfortunate usage since that name is more firmly connected to 10-118. In a modem example of how the reaction is used, addition of tert-butyl acetate to LDA in hexane at -78°C gives the lithium salt of ferf-butyl acetate, " (12-21) an enolate anion. Subsequent reaction a ketone provides a simple rapid alternative to the Reformatsky reaction (16-31) as a means of preparing P-hydroxy erf-butyl esters. It is also possible for the a carbon of an aldehyde or ketone to add to the carbonyl carbon of a carboxylic ester, but this is a different reaction (10-119) involving nucleophilic substitution and not addition to a C=0 bond. It can, however, be a side reaction if the aldehyde or ketone has an a hydrogen. [Pg.1224]

Addition reactions such as A-alkylation do not occur readily, and trimethylsilylmethylation of 3,4-diphenyl-l,2,5-thiadiazole 8 with trimethylsilylmethyl trifluoromethanesulfonate at 80°C occurred at N-2 < 1999J(P1) 1709>. The electron-rich 3-hydroxy-l,2,5-thiadiazole can be preferentially methylated on N-2 using trimethyl orthoacetate in toluene to afford the 2-methyl-l,2,5-thiadiazol-3-one in 69% yield <2002EJ01763>, although a mixture of 3-hydroxythiadiazole and neat trimethyl orthoacetate showed a 20 80 ratio of N- versus 0-alkylation products by H NMR. Treatment of 3-hydroxy-l,2,5-thiadiazole with /-butyl acetate under acid catalysis (Amberlyst 15) gave almost exclusively the A-alkylated compound <2002BMC2259>. [Pg.528]

Uses Preparation of butyl esters (e.g., butyl acetate, di-n-butyl phthalate), glycol ethers solvent for waxes, resins, gums, and varnishes hydraulic fluid ingredient in perfumes and flavors additive in deicing fluids polishes, floor cleaners, stain removers, and in some gasolines (antiicing) diluent for brake fluids humectant for cellulose nitrate. [Pg.209]

The Michael additions of various carbon nucleophiles such as cyanide [15b, 22b], anions generated from nitromethane [27], ferf-butyl acetate [9], malon-ates [27] and O Donnell s glycine equivalent [541, cuprates [9,15b] or Grignard reagents [53] under copper catalysis [55] have also been reported (Scheme 24). [Pg.171]

Palladium(II) effects orthometalation of acetanilides to form the corresponding palladacycles [185]. De Vries, van Leeuwen, and coworkers exploited this reactivity to achieve regioselective oxidative coupling of acetaniUdes and n-butyl acrylate that proceeds efficiently with BQ as the stoichiometric oxidant (Eq. 46) [ 186], The use of TsOH as an additive and acetic acid as a cosolvent significantly improves the results. Inferior results are observed with hydrogen peroxide or copper(II) acetate as the stoichiometric oxidant, but efforts to use molecular oxygen were not described. [Pg.104]

Firedamp-proof Detonators. Firedamp-proof detonators have net received tht attention that firedamp-proof expls have, possibly because the expln of the, detonator is lost in the immediately succeeding expln of the main charge. Treatment of the detonator charge in caps follows similar lines to treatment of Dynamites in the addition of cooling additives, such as salts or wax (Ref 1), BuOAc (butyl acetate) (Ref 2), or poly car boxy lie acids, oxygenated poly carboxylic acids, halogen substituted poly carboxylic and oxygenated polycarboxylic acids, and the neutral and acid salts of these (Ref 4)... [Pg.412]

Esterification of linalool requires special reaction conditions since it tends to undergo dehydration and cyclization because it is an unsaturated tertiary alcohol. These reactions can be avoided as follows esterification with ketene in the presence of an acidic esterification catalyst below 30 °C results in formation of linalyl acetate without any byproducts [71]. Esterification can be achieved in good yield, with boiling acetic anhydride, whereby the acetic acid is distilled off as it is formed a large excess of acetic anhydride must be maintained by continuous addition of anhydride to the still vessel [34]. Highly pure linalyl acetate can be obtained by transesterification of tert-butyl acetate with linalool in the presence of sodium methylate and by continuous removal of the tert-butanol formed in the process [72]. [Pg.45]

The synthesis of bicyclo[n. 1.0]alkanes (82) from various 1-chlorovinyl p-tolyl sulfoxides (80) and lithium enolate of ieri-butyl acetate, propionate and hexanoate through the adducts (81) are summarized in Table 3. As shown in Table 3, addition reaction of tert-butyl carboxylates to 1-chlorovinyl p-tolyl sulfoxides (80) proceeds smoothly to afford the adducts (81) in high to quantitative yields. Cyclopropanation of 81 with i-PrMgCl... [Pg.733]

Starting from optically active 1-chlorovinyl p-tolyl sulfoxide derived from 2-cyclohex-enone, the asymmetric synthesis of cyclopropane derivative (85) was realized (equation 23) . Addition reaction of lithium enolate of tert-butyl acetate to 83 gave the adduct (84) in 96% yield with over 99% ee. Treatment of the latter with i-PrMgCl in a similar way as described above afforded optically pure (15,6/ )-bicyclo[4.1.0]hept-2-ene (85) in 90% yield. [Pg.734]

Addition of r-butyl acetate to lithium diisopropylamide (LDA) in hexane at - 78°C gives the lithium salt of r-butyl acetate456 (2-22) as a stable solid. The nmr and ir spectra of this... [Pg.931]

Chromosomal aberrations in peripheral lymphocytes were also reported in a study of about 40 workers who had been occupationally exposed to trace quantities of 2-butanone (methyl ethyl ketone), butyl acetate, toluene, cyclohexanone and xylene in addition to dimethylfonnamide. Blood samples were taken at two Ibur-nionth intervals, when exposure was to an average of 180 and 150 mg/nr dimethylformamide, respectively. The frequencies of chromosomal aberrations were 3.82% and 2.74% at these two sampling times. Subsequent sampling at tliree six-month intervals, when average dimethylformamide exposures were to 50, 40 and 35 mg/m- , gave lower aberration frequencies of 1.59%, 1.58% and 1.49%. Aberration frequencies in two control groups were 1.61% and 1.10% (Koudela Spazier, 1981). [Pg.555]

Aminopenicillanic acid (2.16 g) is dissolved in 20 ml of a one molar aqueous solution of potassium bicarbonate and 10 ml of acetone. The resultant solution is cooled in an ice-water bath and to it is added with stirring a solution of 2.7 g of alpha-methoxy-3,4-dichloro-phenylacetyl chloride in 10 ml of acetone. The pH is adjusted to 7-8 and upon completion of the addition the reaction medium is stirred for 15 min at ice bath temperature and then for 2.5 h at room temperature, maintaining the pH range between 7 and 8. The solution is extracted once with ether and then adjusted to pH 2.5 with 20% phosphoric acid. The acidic solution is extracted once with 30 ml of butyl acetate and again with 10 ml of butyl acetate. These combined butyl acetate extracts are thereafter successively washed twice with water and reextracted at pH 7 with 0.5 N aqueous potassium hydroxide solution. The aqueous layer is washed twice with ether and the remaining organic solvent is then removed by evaporation under reduced pressure. The washed aqueous layer is then lyophilized and the residue thus obtained taken up in acetone. The crystal line product is collected by filtration and dried to yield the potassium salt of 6-(a-methoxy-3,4-dichlorophenylacetamido)penicillanic acid. Upon treatment with mineral acid of an aqueous solution of the compound so prepared, there is obtained the free acid, 6-(a-methoxy-3,4-dichlorophenylacetamido)penicillanic acid. [Pg.1092]


See other pages where Addition butyl 2- acetate is mentioned: [Pg.182]    [Pg.190]    [Pg.198]    [Pg.29]    [Pg.404]    [Pg.489]    [Pg.834]    [Pg.94]    [Pg.91]    [Pg.98]    [Pg.479]    [Pg.238]    [Pg.569]    [Pg.39]    [Pg.12]    [Pg.150]    [Pg.29]    [Pg.29]    [Pg.324]    [Pg.265]    [Pg.92]    [Pg.229]    [Pg.5]    [Pg.350]    [Pg.176]    [Pg.583]    [Pg.321]    [Pg.728]    [Pg.1093]    [Pg.147]   
See also in sourсe #XX -- [ Pg.168 ]




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