4-Ethyl-2,6-dimethyl-pyridine

The contents of the flask while still hot are poured into a 30-cm. evaporating dish and the alcohol is evaporated on a steam bath. The dry salt is pulverized and thoroughly mixed with 390 g. of calcium oxide, placed in a 2-I. copper retort (Note 3), and heated with the full flame of a Meker burner. The distillate is placed in a distilling flask and heated on a steam bath all material distilling under 90 is removed and discarded. The residue is then allowed to stand over solid potassium hydroxide for twelve hours and is finally fractionated. The dimethyl-pyridine distils at i42-i44°/743 mm. The yield is 35-36 g. or 62-64 per cent of the theoretical amount based on the 3,5-dicarb-ethoxy-2,6-dimethylpyridine, or 30-36 per cent based on the original ethyl acetoacetate. 

To a stirred suspension of N-(2,6-dimethyl-4-oxopyridin-l-yl)pyridin-ium tetrafluoborate (0.58 g, 2 mmol) in dry acetonitrile (20 ml) under nitrogen was added trimethyl phosphite (0.25 g, 2 mmol), followed by finely divided sodium iodide (0.30 g, 2 mmol). After 1 h at 25°C, the solvent was removed under reduced pressure, and water (20 ml) was added. The mixture was extracted with methylene chloride (3 x 15 ml), and the extracts were dried over magnesium sulfate, filtered, and evaporated under reduced pressure. The residue was dissolved in ethyl acetate (40 ml), heated at reflux for 4 h, evaporated under reduced pressure, and eluted on an alumina column (grade 1, neutral) with chloroform to yield pure dimethyl pyridin-4-ylphosphonate (0.36 g, 96%) of melting point (mp) 139 to 140°C. 

Chloroform Dioxane Dioxane- Pyridine Ethyl Dimethyl-... 

Omeprazole is obtained [15] by the reaction of acetyl ethyl propionate 1 with ammonia to give ethyl -3-amino-2,3-dimethyl acrylate 2. Compound 2 was converted to to 2,4-dihydroxy-3,5,6-trimethyl pyridine 3 by treatment with methyl diethylmalonate. Treatment of compound 3 with phosphorous oxychloride produced 2,4-dichloro-3,5/6-trimethyl pyridine 4. 4-Chloro-3/5,6-trimethyl pyridine 5 was obtained by treatment of compound 4 with hydrogen. On treatment of compound 5 with hydrogen peroxide and acetic acid, 4-chloro-3,5,6-trimethyl-pyridine-N-oxide 6 was produced. Treatment of compound 6 with acetic anhydride gave 4-chloro-2-hydroxymethyl-3,5-dimethyl pyridine 7 which was converted to 2-hydroxymethyl-3,5-dimethyl-4-methoxypyridine 8 by treatment with sodium methoxide. Compound 8 was treated with thionyl chloride to produce 2-chloromethyl-3,5-dimethyl-4-methoxypyridinc 9. Compound 9 interacts with 5-methoxy-2-mercaptobenzimidazole to give 5-methoxy 2-[((4-methoxy-3,5-dimethyl-2-pyridinyl)methyl)thio]-lH-bcnzimidazole 10 which is oxidized to omeprazole 11. 

Preparation of the reference mixture in the same matrix as the wastewater samples, namely the wastewater itself, was investigated for minimizing sample differences and their effect on peak retention-time behavior. The same series of 17 reference compounds was added to a sample of Oxy-6 gas condensate. A sufficient amount of each reference was added to swamp any nearby wastewater headspace peak. Triplicate analysis were run, and the computed retention indices for the reference compounds and the unknown wastewater headspace peaks were stastically compared. The results (Table 1, column V Fig. 2, peaks with asterisks) show a substantially improved correlation. Fourteen of the 17 reference compounds, including all the methyl- and ethyl-pyridine isomers, were correlated with wastewater peaks. Since 7 of the correlated peaks were among the 22 peaks proviously shown (see Section 32) to be common to the 8 wastewater samples (Table 1), these compounds may be presumed to be present in all the waters 2- and 3-methyl- 2-, 3-, and 4-ethyl- 2,4-dimethyl- and 2,6-dimethyl-pyridines. Furthermore, the 37 peaks cotmnon to Oxy-6 gas condensate and Oxy-7 and 8 gas condensate (see Section 32) included 11 of the... 

Pyridine, 2-ethyl-3,5-dimethyl- = Pyridine, 2,4-dimethyI-6-ethyl- 2545, 2761, 2762, 4249 ... 

Lutidins.—Theoretically there are three possible ethyl-pyridins, CsHiNtCjHo), and six possible dimethyl-pyridins, CsHsNfCHs). The former are all known, and three of the latter. 

Chloro-a-2-(dimethylamino) ethyl benzyl) pyridine bimaleate 2-(p-Chloro-a-(2-(dimethylamino) ethyl) benzyl) pyridine maleate (1 1) Y-(4-Chlorophenyl)-N,N-dimethyl-... 

Pyridines and pyrazines, such as 2-ethylpyridine, 2,3,5-trimethyl pyridine, 2-ethyl-3,5-dimethyl pyridine, 2,3-dimethylpyrazine and 2,5-dimethylpyrazine, are the most prominent classes of odorous compounds identified as being responsible for the odour of a cigar smoker s breath. They may be generated during cigar pyrrolysis by cleavage of nicotine or by Maillard reaction. 

Chapter V. Quinaldine (V,2) 2-methyl-, 2 5-dimethyl- and 2-acetyl-thiophene (V,8-V,10) 2 5-dimethyl and 2 4-dimethyl-dicarbethoxy-p3nrole (V,12-V,13) 2-amino- and 2 4 dimethyl-thiazole (V,15-V,16) 3 5-dimethyl-pyrazole (V,17) 4-ethylp3rridine (from pyridine) (V,19) n-amyl-pyridines from picolines) (V,28) picolinic, nicotinic and isonicotinic acid (V,21-V,22) (ethyl nicotinate and p-cyanop3n idine (V,23-V,24) uramil (V,25) 4-methyl-(coumarin (V,28) 2-hyi-oxylepidine (V,29). 

Pyrrole oxidizes in air to red or black pigments of uncertain composition. More usehil is the preparation of 2-oxo-A -pyrrolines, which is best carried out by oxidation of the appropriate pyrrole with in pyridine (37), eg, 3,5-dimethyl-ethyl-3-pyrrolin-2-one [4030-24-4] from... 

Etherification. The reaction of alkyl haUdes with sugar polyols in the presence of aqueous alkaline reagents generally results in partial etherification. Thus, a tetraaHyl ether is formed on reaction of D-mannitol with aHyl bromide in the presence of 20% sodium hydroxide at 75°C (124). Treatment of this partial ether with metallic sodium to form an alcoholate, followed by reaction with additional aHyl bromide, leads to hexaaHyl D-mannitol (125). Complete methylation of D-mannitol occurs, however, by the action of dimethyl sulfate and sodium hydroxide (126). A mixture of tetra- and pentabutyloxymethyl ethers of D-mannitol results from the action of butyl chloromethyl ether (127). Completely substituted trimethylsilyl derivatives of polyols, distillable in vacuo, are prepared by interaction with trim ethyl chi oro s il an e in the presence of pyridine (128). Hexavinylmannitol is obtained from D-mannitol and acetylene at 25.31 MPa (250 atm) and 160°C (129). 

NOTE - Petrochemical plants also generate significant amounts of solid wastes and sludges, some of which may be considered hazardous because of the presence of toxic organics and heavy metals. Spent caustic and other hazardous wastes may be generated in significant quantities examples are distillation residues associated with units handling acetaldehyde, acetonitrile, benzyl chloride, carbon tetrachloride, cumene, phthallic anhydride, nitrobenzene, methyl ethyl pyridine, toluene diisocyanate, trichloroethane, trichloroethylene, perchloro-ethylene, aniline, chlorobenzenes, dimethyl hydrazine, ethylene dibromide, toluenediamine, epichlorohydrin, ethyl chloride, ethylene dichloride, and vinyl chloride. 

Abbreviations Aik, alkyl AN, acetonitrile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene Cp, cy-clopentadienyl Cp , pentamethylcyclopentadienyl Cy, cyclohexyl dppm, diphenylphosphinome-thane dpme, Ph2PC2H4PMe2 Et, ethyl fod, 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octane-dionate HOMO, highest occupied molecular orbital LUMO, lowest unoccupied molecular orbital Me, methyl MO, molecular orbital nbd, norbornadiene Nuc, nucleophile OTf, triflate Ph, phenyl Pr, propyl py, pyridine THE, tetrahydrofuran TMEDA V,V,M,M-tetramethylethylenediamine. 

Reaction of -picoline over degassed Raney nickel was found to give 5,5 -dimethyl-2,2 -bipyridine (5), the structure of which was established by its synthesis from 2-bromo-5-methylpyridine. Oxidation of this dimethyl-2,2 -bipyridine, and similar oxidation of the diethyl-2,2 -bipyridine derived from 3-ethylpyridinc, gave the corresponding dicarboxylic acid and the same acid was produced by the action of degassed Raney nickel on sodium nicotinate (in water) or on ethyl nicotinate. These transformations established the 5,5 -substitution pattern for three 2,2 -bipyridines derived from 3-substituted pyridines but such evidence is not available for the biaryls... 

Abbreviations aapy, 2-acetamidopyridine Aik, alkyl AN, acetoniuile Ar, aryl Bu, butyl cod, 1,5-cyclooctadiene COE, cyclooctene COT, cyclooctatetraene Cp, cyclopentadienyl Cp , penta-methylcyclopentadienyl Cy, cyclohexyl DME, 1,2-dimethoxyethane DME, dimethylformamide DMSO, dimethyl sulfoxide dmpe, dimethylphosphinoethane dppe, diphenylphosphinoethane dppm, diphenylphosphinomethane dppp, diphenylphosphinopropane Et, ethyl Ec, feirocenyl ind, inda-zolyl Me, methyl Mes, mesitylene nb, norbomene orbicyclo[2.2.1]heptene nbd, 2,5-norbomadiene OTf, uiflate Ph, phenyl PPN, bis(triphenylphosphoranylidene)ammonium Pi , propyl py, pyridine pz, pyrazolate pz, substituted pyi azolate pz , 3,5-dimethylpyrazolate quin, quinolin-8-olate solv, solvent tfb, teti afluorobenzobaiTelene THE, tetrahydrofuran THT, tetrahydrothiophene tmeda, teti amethylethylenediamine Tol, tolyl Tp, HB(C3H3N2)3 Tp , HB(3,5-Me2C3HN2)3 Tp, substituted hydrotiis(pyrazol-l-yl)borate Ts, tosyl tz, 1,2,4-triazolate Vin, vinyl. 

The crude product obtained above is dried in high vacuum and then dissolved in 4 cc of pyridine. About 3 cc of acetic anhydride is added. The mixture is then heated on the steam bath for about 15 minutes and then evaporated to dryness in vacuo. About 20 cc of water is added. The product is then extracted into 150 cc of ethyl acetate, washed with saturated sodium bicarbonate solution and water, and dried over sodium sulfate. The solvent is removed in vacuo to give a residue which is crystallized from ethyl acetate-benzene to yield about 250 mg of 11/3,17a,21-trihydroxy-6,16a-dimethyl-20-oxo-2 -phenyl-4,6-pregnadieno-[3,2-c] pyrazole 21-aCetate, as described in U.S. Patent 3,300,483. 

To 6a-fluoro-16a-hydroxy-hydrocortisone 21-acetate, described by Mills et al, J. Am. Chem. Soc., volume 81, pages 1264 to 1265, March 5, 1959, there was added acetic anhydride in dry pyridine. The reaction mixture was left at room temperature overnight and was then poured with stirring into ice water. The resulting precipitate was filtered, washed with water and crystallized from acetone-hexane to give 6a-fluoro-16a-hydroxy-hydrocortisone-16a,21-diacetate. This was reacted with methane-sulfonyl chloride in dimethyl formamide in the presence of pyridine at 80°C for 1 hour. The mixture was cooled, diluted with water and extracted with ethyl acetate. The extract was washed with water, dried over anhydrous sodium sulfate and the ethyl acetate was evaporated. By recrystallization of the residue from acetone-hexane there was obtained 6a-fluoro-A <" -pregnadiene-16o ,17a,21-triol-3,20-dione 16a,21 diacetate. 

To a solution of 13 parts of compound A and 12 parts by volume of absolute pyridine in 80 parts by volume of absolute dioxane there are added dropwise and under constant stirring 35 parts of 3,4.5-trimethoxybenzoyl chloride dissolved in 70 parts by volume of absolute dioxane in the course of 30 minutes. The mixture is stirred for a further 3 hours at a temperature of 100°C and the excess solvent is then evaporated in vacuo. The residue of the evaporation is treated with ethyl acetate and saturated sodium carbonate solution, whereafter the organic phase is separated, treated with water, dried with sodium sulfate and the solvent is removed in vacuo. The residue thus obtained is taken up In ether and separated from 4 parts of insoluble trimethoxybenzoic acid anhydride by filtration. After evaporation of the ether there are obtained 32.5 parts of N,N -dimethyl-N,N -bis-[3-(3,4,5-trlmethoxybenzoxy)-propyl] -athylene diamine, corresponding to a yield of 86% of the theoretical. MP 75°C to 77°C. 

A mixture of 50 grams of a-dl-1,2-diphenyl-2-hydroxy-3-methyl-4-dimethylaminobutane hydrochloride, 50 grams of propionic anhydride and 50 cc of pyridine was refluxed for about 5 hours. The reaction mixture was cooled to 50°C and ethyl ether was added to the point of incipient precipitation. The hydrochloride salt of 0 -dl-l,2-diphenyl-2-propion-oxy-3-methyl-4-dimethylamlnobutane formed in the reaction precipitated upon cooling and was removed by filtration and washed with anhydrous ether. On recrystallization from a mixture of methanol and ethyl acetate, a-dl-l, 2-diphenyl-2-propionoxy-3-methyl-4-dimethyl amlnobutane hydrochloride melted at 170°-171°C. 

The sodium and potassium salts of glutaconaldehyde are soluble only in polar solvents such as water, dimethyl sulfoxide, N,N-dimethylformamide, pyridine, and methanol. However, the stable tetrabutylammonium salt is soluble in relatively nonpolar solvents such as chloroform and ethyl acetate. It may be prepared from the potassium salt in the following manner. In a 1-1. Erlenmeyer flask equipped with a magnetic stirring bar are placed a solution of 13.6g. (0.1 mole) of crude glutaconaldehyde potassium salt in 200 ml. of water and a solution of 33.9 g. (0.1 mole) of tetrabutyl-ammonium hydrogen sulfate in 200 ml. of ice-cold water, the pH of wliich was adjusted to 10 by adding aqueous 2M sodium hydroxide. 

---