Acetate derivatives, ethyl

The above example serves to iUustrate the basis of the procedure employed for the characterisation of aUphatic esters, viz., hydrolysis to, and identification of, the parent acids and alcohols. Most esters are liquids a notable exception is dimethyl oxalate, m.p. 54°. Many have pleasant, often fruit-hke, odours. Many dry esters react with sodium, but less readily than do alcohols hydrogen is evolved particularly on warming, and a sohd sodio derivative may separate on coohng (e.j/., ethyl acetate yields ethyl sodioacetoacetate ethyl adipate gives ethyl sodio cj/cZopentanone carboxylate). 

Various 4-, 5-, or 4,5-disubstituted 2-aryIamino thiazoles (124), R, = QH4R with R = 0-, m-, or p-Me, HO C, Cl, Br, H N, NHAc, NR2, OH, OR, or OjN, were obtained by condensing the corresponding N-arylthiourea with chloroacetone (81, 86, 423), dichloroacetone (510, 618), phenacyichloride or its p-substituted methyl, f-butyl, n-dodecyl or undecyl (653), or 2-chlorocyclohexanone (653) (Method A) or with 2-butanone (423), acetophenone or its p-substituted derivatives (399, 439), ethyl acetate (400), ethyl acetyl propionate (621), a- or 3-unsaturated ketones (691), benzylidene acetone, furfurylidene acetone, and mesityl oxide in the presence of Btj or Ij as condensing agent (Method B) (Table 11-17). 

Figure 20 1 shows the structures of various derivatives of acetic acid (acetyl chlo ride acetic anhydride ethyl thioacetate ethyl acetate and acetamide) arranged m order... 

A (4-Hydroxyphenyl)glycine. This derivative (23) forms aggregate spheres or shiny leaflets from water. It turns brown at 200°C, begins to melt at 220°C, and melts completely with decomposition at 245 —247°C. The compound is soluble in alkaU and mineral acid and sparingly soluble in water, glacial acetic acid, ethyl acetate, ethanol, diethyl ether, acetone, chloroform, and benzene. 

In detergent perfumes, the stabiUty of vanillin is not always certain. It depends on the association made with other raw materials, eg, with patchouli, frankincense, cloves, most of the animal notes, and such chemicals as amyl saUcylate, methyl ionones, heflotropin, gamma undecalactone, linalool, methyl anthrarulate, benzyl acetate, phenyl ethyl alcohol, cedar wood derivatives, oak mosses, coumarin, benzoin. Pern balsam, and cistus derivatives. In some cases, these mixtures can cause discoloration effects. 

Acid moieties include formic acid itself, formates and orthoesters, formamide, DMF dimethyl acetal and ethyl diethoxyacetate, acids, acid chlorides and anhydrides, the last including a rare [3,4-oxalate esters, 2-acyl or 2-ethoxycar-bonyl derivatives e.g. 180) are formed. 

Preparation of the acetate derivative Evaporate the extract to dryness. Add 50 fil of three parts acetic anhydride and two parts pyridine. Heat at 60° for 1 hour. Evaporate to dryness with clean, dry nitrogen and dissolve the residue in 25 ju.1 of ethyl acetate. 

Reaction of a-phenylsulfinyl acetate or ethyl a-(t-butylsulfmyl)acetate with one equivalent of ethylmagnesium bromide or iodide was shown to give the corresponding Grignard reagent 129 or 132, which upon reaction with carbonyl compounds afforded the corresponding adducts. Thus Nokami and coworkers prepared ethyl / -hydroxycarboxylates 130167, jS-keto esters 131168, a,/J-unsaturated esters 133169 and other derivatives by this method. 

Chelation-controlled product is formed from reaction of a-benzyloxypropanal and the TBDMS silyl ketene acetal derived from ethyl acetate using 3% LiC104 as catalyst.94... 

It has been shown by Zanardi, Nanni and coworkers that, instead of isocyanides, isothiocyanates can be used in the radical process [90]. Treatment of the mixture of the diazonium tetrafluoroborates 3-217 and the isothiocyanates 3-218 with pyridine or a mixture of 18-crown-6 and potassium acetate in ethyl acetate, furnished the benzothienoquinoline derivatives 3-219. In addition, in some cases the rearranged products 3-220 were furnished in low to reasonable yields (Scheme 3.57). 

The treatment of (2-benzoylamino-5-iodobenzoyl-amino)acetic acid ethyl ester 88 with hydrazine hydrate for 4h yielded hydrazine derivative 2-benzoylamino-iV-hydrazinocarbonylmethyl benzamide 89, which on refluxing with sodium acetate and acetic acid for 8 h resulted in the formation of 6-iodo-10-phenyl-3//-3,4,9,10a-tetra-azaphenanthren-2-one 90 <2000IJH59> (Scheme 5). 

The efficiency of catalysts 86-89 for the asymmetric aldol reaction of a series of nucleophiles toward benzyloxyacetaldehyde was studied. For example, compound 89c was found to be an excellent catalyst for the asymmetric aldol reaction of silylketene acetal derivatives of t-butyl thioacetate, ethyl thioacetate, and ethyl acetate with benzyloxyacetaldehyde. In the presence of 0.5 mol% of the catalyst, the asymmetric aldol reaction took place at —78°C in CH2C12, affording the respective /i-hydroxy esters with excellent enantioselectivity (Scheme 3-32). 

CHLOROCYCLOBUTANE, 51, 106 Mesitylene, cyanation, 50, 54 METHALATION OF 2-METHYLPYRIDINE DERIVATIVES ETHYL 6-METHYL-PYRIDINE-2-ACETATE, 52, 75 Metalation, directed, 53, 59 Methallyl alcohol, with phenyl-mercuric acetate to yield 2-methyl-3-phenylpropional-dehyde, 51, 17 METHALLYLBENZENE, 52, 115 7r-Methallylnickel bromide, 52, 115... 

For example, Nakamura and Kuwajima [15] have described 1-alkoxy-l-trimethylsilyloxycyclopropanes (15) -prepared by reductive silylation of alkoxy 3-chloropropanoates-, which react with aliphatic aldehydes, but not with ketones, in the presence of one equivalent of TiCl4 to give good yields of y-lactones 17 through the acyclic derivative ethyl 4-hydroxybutanoate (16) (Scheme 5.10). With aromatic aldehydes and their acetals the reaction leads directly to acyclic 1,4-D derivatives. 

METALATION OF 2-METHYLPYRIDINE DERIVATIVES ETHYL 6-METHYLPYRIDINE-2-ACETATE... 

Ethyl pyridine-2-acetate and ethyl 6-methylpyridine-2-acetate have previously been prepared by carboxylation of the lithio derivatives of a-picoline and lutidine, respectively. Use of ethyl carbonate to acylate the organometallic derivative avoids the intermediacy of the (unstable) carboxylic acid, and the yields are better. In the present procedure potassium amide is used as the metalating agent the submitters report that the same esters may be formed by metalation with sodium amide (43% yield) or with w-butyllithium (39% yield). The latter conditions also yield an appreciable amount of the acid (which decarboxylates). 

The different structures and seven-membered-r1ng orthoesters the C-n.m.r. chemical shift of atom as a probe for the assignment the now we 1 1 -e s t aii 1 i shed criteria references cited therein). Table T range- , for ethyl i dene acetals ( 13), (67), and o r t h OG n t f. r. As ex pec terl observed in goi rig from acetals to p.p.m. from isopropv1idene acetal derivatives). 

Cellulose derived-acetate, acetate butyrate, ethyl, nitrate Chlorinated rubbers... 

A typical example that illustrates the method concerns the lipase- or esterase-catalyzed hydrolytic kinetic resolution of rac-1-phenyl ethyl acetate, derived from rac-1-phenyl ethanol (20). However, the acetate of any chiral alcohol or the acetamide of any chiral amine can be used. A 1 1 mixture of labeled and non-labeled compounds (S)- C-19 and (f )-19 is prepared, which simulates a racemate. It is used in the actual catalytic hydrolytic kinetic resolution, which affords a mixture of true enantiomers (5)-20 and (J )-20 as well as labeled and non-labeled acetic acid C-21 and 21, respectively, together with non-reacted starting esters 19. At 50% conversion (or at any other point of the kinetic resolution), the ratio of (5)- C-19 to (1 )-19 correlates with the enantiomeric purity of the non-reacted ester, and the ratio of C-21 to 21 reveals the relative amounts of (5)-20 and (J )-20 (98). 

Interestingly, exchange of the iodoacrylate to the bromo derivative in 4.38. leads to a different reaction. Dimerization of two hexyne molecules and subsequent attachment of the acrylate gave 2-(2 ,3 ,4 ,5 -tetraethylcyclopentadienyl)-acetic acid ethyl ester in 74% yield.51... 

Synthesis (Kleemann et al. 1999, Janssen (Janssen), 1973 Janssen et al. (Janssen), 1973, Stokbroekx et al., 1973, Niemegeers et al., 1974) ) Treatment of 2-oxo-3,3-diphenyl-tetrahydrofuran, synthesized by treatment of diphenyl-acetic acid ethyl ester with ethylene oxide, with HBr(gas) yields bromo derivative i, which is then converted into butyryl chloride derivative ii by means of thionyl chloride in refluxing chloroform. Reaction of derivative ii with dimethylamine in toluene affords dimethyl (tetrahydro-3,3-diphenyl-2-furylidene)ammonium bromide, which is then condensed with 4-(4-chlorophenyl)-4-piperidinol by means of Na2C03 and Kl in refluxing 4-methyl-2-pentanone to provide loperamide. 

Cyclotrimerization of nitriles is the best-known route to 1,3,5-triazines (for a detailed discussion see CHEC 2.18). The reaction is of value for preparing the symmetrical derivatives only. Nevertheless, many important triazines, such as cyanuric chloride, are made in this way. Other cyclotrimerization reactions are useful thus, an easy route to 1,3,5-triazine involves heating ammonium acetate with ethyl orthoformate. 

Oxidation of the dibutylstannylene acetal derived from 3-0-benzyl-l,2-0-isopropylidene-a-D-glucofuranose (26) with NBS was finished within 5 min. The eluant for column separation was the mixture of hexane and ethyl acetate (from 4 1 to 2 1). Evaporation of solvent from the corresponding fractions afforded 27 (280 mg, 90%). Colorless crystals were obtained from ethyl acetate-hexane mp 117-118°C [ )D -114.5° (c 1.00, chloroform) IR (Nujol) 3491 cm" (OH), 1725 cm"1 (C=0), C-NMR (CDa3,62.90 MHz) 8 208.2 (C-5). 

The product obtained from 2-aminopyridine and ethyl 2-methylaceto-acetate in ethyl polyphosphate was described by Mullock et al.6 as 1,8-naphthyridine, but it was shown later by Bowden and Brown82 to be 2.3-dimethyl-4-oxo-4/f-pyrido[l,2-n]pyrimidine (36 R1 = R2 = Me, R = H). 2-Acetylbutyrolactone (43) and its 5-substituted derivatives have also been used as )3-oxo ester component49-65-83 85. 

Finally, because the amylose molecule is a polyalcohol, chemical derivatives of it can be easily prepared. Included in this are the acetate, methyl, ethyl and similar derivatives, all of which belong to a class of polymers with completely different properties from the parent substance. Many of these derivatives demonstrate useful film and fiber properties, but they have not reached significant commercial utilization. All any lose derivatives crystallize easily, and many show interesting features in their crystalline state. 

Platform chemicals are compounds that serve as building blocks for numerous chemical intermediates and end products. An example is ethylene, which serves as the feedstock for derivatives such as acetaldehyde, ethylene dichloride, ethylene oxide, polyethylene, vinyl acetate, and ethyl acetate. Biobased chemicals such as succinic acid, 3-hydroxypropionic acid (3-HP), and butanol also have the potential to be converted into multiple derivatives, some of which are commodity chemicals and others that are higher-value chemicals. 

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