Ethers, diethyl potassium salts

The pH of the mixture was adjusted to 7.5 by adding a saturated sodium bicarbonate solution. After being washed twice with diethyl ether, the reaction solution was acidified to pH 2 with dilute hydrochloric acid and extracted with ether. The ether solution containing the free penicillin was washed twice with water and then extracted with 50 ml of N potassium bicarbonate solution. After freeze drying of the obtained neutral solution, the potassium salt of o-azidobenzylpenicillin was obtained as a slightly colored powder (11.2 grams, 54% yield) with a purity of 55% as determined by the hydroxylamine method (the potassium salt of penicillin G being used as a standard). 

At the end of this time the crystalline precipitate which had formed was filtered off with suction, washed with diethyl ether, and dried in a vacuum desiccator. The product comprised essentially the potassium enolate of ethyl fluoromalonaldehydate (alternative nomenclature, the potassium salt of fluoromalonaldehydic acid ethyl ester). 

The product was shown to be the THE adduct, but a later modification of the procedure by E. 0. Fischer and H. Fischer (99), using benzene or diethyl ether in place of THE and the potassium salt in place of the sodium salt of cyclopentadiene, produced solvent-free complexes of Tb, Ho, Tm and Lu. The remaining tricyclopentadienides have since been made by various workers using similar methods (53, 100, 101). All of the complexes behave similarly. They are very air- and moisture-sensitive, are stable to heat, and sublime, except for the europium derivative, at elevated temperatures. They are insoluble in cyclohexane, benzene... 

The same general method has been used by the submitters to prepare diethyl acetylenedicarboxylate. In this case absolute ethanol was used, and the ether extract was dried over anhydrous magnesium sulfate. The yield of diethyl ester from 100 g. of the acid potassium salt of acetylenedicarboxylic acid was 57-59 g. (51-53%) b.p. 96-98°/8 mm. n 1.4397. 

The second route to salts of the [B9H14] anion, described below, is accomplished by base degradation of B, 0H u (which is a moderately air-stable solid) followed by acid hydrolysis, yielding an aqueous solution of the [B9H14] anion.6 The potassium salt is precipitated by addition of K2C03, and the K[B9H14] is then purified by extraction with diethyl ether. 

To a solution of 4,6-dichloro-5-(o-methoxyphenoxy)-2-(4-pyridyl)-pyrimidine (6g) dissolved in 100 ml THF was added 4-t-butyl benzene sulfonamide potassium salt at ambient temperature and the mixture stirred overnight. The reaction mixture was then poured into 150 ml of water and diethyl ether and the pH adjusted to 5 by the addition of HO Ac. Thereupon a precipitate formed and the product isolated by filtration as a beige crystal. MS data supplied. 

This solution is used to obtain either the acid or the potassium salt. To obtain the acid, the solution is transferred to a 750-mL separatory funnel. The acid is extracted by addition of 80mL of diethyl ether and 120mL of a mixture of equal volumes of diethyl ether and concentrated HCl chilled to — 20 °C. The heaviest layer is collected, and diethyl ether is removed under vacuum. The acid is crystallized by slow evaporation of its water solution. 

A two-step procedure is employed based on the literature procedure for LMe , Pr2MnI(THF), which first generates the potassium salt KLMe Pr2 prior to its reaction with MnL.1 The preparation of the potassium salt of the p-diketimine fl Me, Pr2 was reported by Mair and coworkers from HLMe, Pr2 and KN(SiMe3)2 in relatively low yield (27%).2 Winter and coworkers have reported a related THF adduct from KH.3 Here, the same reagents in diethyl ether give a base-free potassium salt that was used to introduce LMe Pr2 into manganese and zinc complexes. 

A solution of 14 g (0.05 mole) of the potassium salt of c/s-diammine-di(carbonato)cobaltate(III) in 150 mL of cold water is charged on a column containing Dowex 50W-X8 resin in the Li+ form (100-200 mesh, 7 cm x 15 cm). With the addition of cold water, a blue solution effuses from the column. To the effluent is added 3 g of ammonium carbonate and the solution is concentrated to 50 mL under reduced pressure at 35°. The concentrated solution is filtered and kept in a refrigerator until blue crystals of lithium m-diammi-nedi(carbonato)cobaltate(IQ) deposit. This crude product is recrystallized from water, collected on a filter, washed with cold water, ethanol, and diethyl ether, and finally dried under vacuum. The yield is 3 g. Anal. Calcd. for Li[Co(C03)2(NH3)2] C, 10.92 H, 2.75 N, 12.73. Found C, 10.92 H, 3.04 N, 12.66. The solubility of this salt in water is considerably lower than that of the potassium salt. 

Sample preparation Filter microbial cell suspensions. 4 mL Filtrate + 200 pL water + 100 pL 4 pg/mL 4 -hydro Qrwarfarin alcohols (potassium salt) in water -I- 4 mL cyclohexane dichloromethane 90 10, extract twice, discard organic layers. Extract aqueous layer with 5 mL ethyl acetate. Extract the organic phase with 2 mL 100 mM KOH. Acidify the aqueous phase with 1 mL 5 M HCl, extract with 5 mL diethyl ether. Evaporate the ether layer to dryness under a stream of nitrogen, reconstitute the residue in 250 pL mobile phase, inject a 50-200 pL aliquot. 

For the isolation of the dry potassium salt, K[7,8-C2B9H12], the aqueous solution is diluted with an additional 200 mL of water, saturated with carbon dioxide, and an essentially pure product is extracted with three successive 150-mL portions of diethyl ether. Much water is coextracted. The combined extracts are dried with solid potassium carbonate until a water layer separates and is discarded. Then an equal volume of benzene is added to the ether layer, and the drying is continued as long as a water layer is formed. The clear diethyl etherbenzene solution is filtered, and the solvents are evaporated at 50° and 10 torr. The solid residue is then dried under vacuum (100°, 1 torr). After cooling the solid to room temperature, nitrogen is introduced into the evacuated flask. The white solid product (48.3 g, 94.3%) is pure enough for any subsequent synthetic procedure. At ambient temperature in an inert atmosphere, the salt is stable indefinitely. It can be handled briefly in air without any risk, but it is quite hygroscopic. 

DCM and filtering to remove any insoluble components. The products are precipitated using cold diethyl ether, filtered, and dried under high vacuum to yield 4,5 g (90%). The anionic polymerization of macromonomers 11 and 12 (2.6 g) catalyzed by rBuOK (0.10 g) is carried out at 100°C under an argon atmosphere and the sticky point is reached after 30 min. The polymerization is then continued for 12 h. The reaction is quenched by the addition of methanol and the product 13 is granulated through 1-mm sieves. The polymer is stirred in 4 M HCl for 2 h to remove potassium salts and then washed with water and ethanol and dried under high vacuum to yield... 

Meanwhile, the thermometer and stirrer of the reaction flask are replaced with stoppers and the condenser with a drying tube while the system is purged with argon or nitrogen. The reaction flask is then filled with 400 mL of dry diethyl ether and shaken to wash the product from the potassium salts. In order to filter the resulting solution, the drying tube is replaced with a fritted funnel (50-mm diameter coarse glass frit, porosity 3), which is connected to a vertical vacuum adapter topped by a 1-L two-necked flask. The apparatus is then inverted as the... 

Trimethyl-TTF was dissolved in dry THF, and treated with a slight excess of LDA (lithium diisopropylamide) for one hour at -78 C. One equivalent of sulfur was added, and the mixture stired for 2 hours, while the temperature was allowed to rise to -10 C. The mixture was buffered by the addition of one mL of tert-butylalcohol, and a THF-DMF slurry of the potassium salt of 0)-bromohexadecanoic acid was added, and the mixture stirred for 20 hours. Water was added, the mixture was acidified with HCl, and extracted several times with diethyl ether. The product was purified through flash column chromatography (silica/dichloro-methane-acetone gradient) and recrystallization from toluene-hexane. Yields of 5 were typically 30-40%. Compounds 4, 6, 7, and 8 were prepared in a similar manner. 

Classification Sat. aliphatic carboxylic acid salt Definition Potassium salt of stearic acid Empirical C18H36KO2 Formula CH3(CH2)i6COOK Properties Wh. powd., si. fatty odor readily sol. in hot water producing alkaline sol ns. sol. in diethyl ether, ethanol, chloroform, carbon disulfide slowly sol. in cold water m.w. 322.63 Toxicology Essentially nontoxic inh. of high cones, of dust may cause coughing, mild... 

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