Methanol yellow

Phthalylacetic acid. Heat a mixture of 30 g. of phthalic anhydride, 40 ml. of acetic anhydride and 5 g. of potassium acetate under reflux in an oil bath at 155-165° for 15 minutes. Pour the reaction mixture into ice-cold water, collect the yellow precipitate by suction filtration, wash it three times with 25 ml. of water and once with 10 ml. of 50 per cent, ethanol. Dry the. product at 100° the yield of crude plithalylaeetie acid is 20 g. Recrystallise from hot methanol yellow needles, m.p. 245-246°, are obtained. 

When tetrakis[thiourea]tellurium dichloride was reacted with ammonium (diphenylthionophosphinimido) diphenylthiolophosphinate in methanol, yellow crystals of tellurium bis (diphenylthionophosphinimido)diphenylthiolophosphinate] precipitated1. 

Tellurium dioxide dissolved in hydrochloric or hydro bromic acid was treated with an excess of (V-methyl-iV-2-hydroxyethyldithiocarbamic acid in methanol. Yellow crystals of the tellurium tris[dithiocarbamate] halide precipitated1. 

Fine yellow needles from dilute methanol, yellow prisms from undiluted methanol mp 3 [7 -325. Fluoresces in dilute alcoholic oln. uv max (ethanol) 224. 238, 276, 287, 292 314, 329, 375 tun (log 4.39, 4.33 4.70, 4.85, 4.83, 3.66, 3.80, 3 66). Soly in methanol, acetone, chloroform carbon tetrachloride, carbon disulfide, tetrahydrofuran, dioxane less than 1%. 

Again at ambient T, KCN, [Co(NH3)sNCS] and traces of catalytic [Co(CN)5] " first form [Co (NH3)5-NCS-Co"(CN)5]", and then (after adding a little methanol) yellow K3[Co (CN)sSCN] plus Co°. However, K2[Co(CN)s(H20)] and KSCN at 40 °C, after adding ethanol, give K3[Co (CN)sNCS], the isomer this rearranges extremely slowly in water to the other (kS) structure. Other (pseudo)halides, N3, Br and I", also replace the H2O. 

Brady s reagent A solution of 2,4-dinitro-phenylhydrazine sulphate in methanol. Gives characteristic crystalline yellow to deep red 2,4-dinitrophenylhydrazone products with aldehydes and ketones. 

The most common of the xanthophyll pigments, it is present in all green leaves, in blossoms and in various animal sources. It crystallizes in violet prisms with one molecule of methanol m.p. I93 C, soluble in organic solvents giving yellow solutions, li is related to a-carolene in the same way as zeaxanlhin is to /1-carolene. 

Quinaldine Methiodide. Boil a mixture of 3 ml. of quinaldine, 2 ml. of methanol and 3 ml. of methyl iodide gently under reflux for hours, during which the methiodide will start to cry stallise. Cool the mixture thoroughly in ice-water, filter off the methiodide and recrystallise it from ethanol pale yellow crystals, m.p. 194". 

To a few drops of formalin solution add a few drops of dinitro-phenylhydrazine reagent A (p. 263) a yellow precipitate is produced in the cold. Acetaldehyde and acetone give orange-coloured precipitates. Dissolve water-insoluble compounds e.g-y benzaldehyde, salicylalde-hyde, acetophenone and benzophenone) in a small volume of methanol before adding reagent B. With benzophenone the precipitate forms slowly. 

Iodoform Reaction. To 0 5 ml. of ethanol add 3 ml. of 10% KI solution and 10 ml. of NaOCl solution. Warm gently fine yellow crystals of CHI3 separate. Isopropanol gives CHIj in the cold. Pure methanol and the other alcohols in this section go not give the reaction. 

Remove most of the methanol by distillation on a steam bath, and dilute the residue with 100 ml. of water. Extract the mixture with ether, wash the upper layer with water, and dry it rapidly with a little anhydrous magnesium sulphate. Remove the ether by flash distillation, and distil the residual pale yellow oil under diminished pressure. Collect the m-nitrobenzyl alcohol at 183-185°/17 mm. it solidifies to a pale yellow solid, m.p. 30°, when cooled in ice. The yield is 13 g. 

Methylation with diazomethane may be carried out as follows (FUME CUPBOARD )-. Dissolve 2-3 g. of the compound (say, a phenol or a carboxylic acid) in a little anhydrous ether or absolute methanol, cool in ice, and add the ethereal solution of diazomethane in small portions until gas evolution ceases and the solution acquires a pale yellow colour. Test the coloured solution for the presence of excess of diazomethane by removing a few drops into a test-tube and introducing a glass rod moistened with glacial acetic acid immediate evolution of gas should... 

Indane-1 3-dione (1 3-diketohydrindene). Method A. To a solution of sodium methoxide, prepared from 6 1 g. of sodium and 200 ml. of anhydrous methanol, add 15 g. of phthalylacetic acid and allow to stand for 1 hour at room temperature collect the yellow precipitate by suction filtration. Mix the yellow solid with 150 ml. of 10 per cent, sulphuric acid, heat on a steam bath until no more carbon dioxide is evolved (15-20 minutes), filter the hot solution and allow to cool. Collect the yellow crystals by filtration at the pump, wash with a httle water and dry at 100°. The yield of crude 1 3-indanedione, m.p. 125-126°, is 7 g. RecrystaUise from hght petroleum, b.p. 80-100°, and thus obtain the pure product, m.p. 129-130°. 

METHOD 2 [89]--1M MDA or benzedrine and 1M benzaldehyde is dissolved in 95% ethanol (Everclear), stirred, the solvent removed by distillation then the oil vacuum distilled to give 95% yellow oil which is a Schiff base intermediate. 1M of this intermediate, plus 1M iodomethane, is sealed in a pipe bomb that s dumped in boiling water for 5 hours giving an orangy-red heavy oil. The oil is taken up in methanol, 1/8 its volume of dH20 is added and the solution refluxed for 30 minutes. Next, an equal volume of water is added and the whole solution boiled openly until no more odor of benzaldehyde is detected (smells like almond extract). The solution is acidified with acetic acid, washed with ether (discard ether), the MDMA or meth freebase liberated with NaOH and extracted with ether to afford a yield of 90% for meth and 65% for MDMA. That s not a bad conversion but what s with having to use benzaldehyde (a List chemical) Strike wonders if another aldehyde can substitute. 

A solution of 1.05 M diborane in THF (25 ml, 26 mraol) was added slowly to a stirred suspension of 3-acetyl-5-hydroxy-2-methylindole (1.0 g, 5.3 mmol) in THF (10 ml). After hydrogen evolution ceased, the mixture was heated at reflux for I h, cooled and poured into acetone (75 ml). The mixture was heated briefly to boiling and then evaporated in vacuo. The residue was heated with methanol (50ml) for 20min. The solution was concentrated and 3NHC1 (40ml) was added. The mixture was extracted with ether and the extracts dried (MgSO ) and evaporated to yield a yellow oil. Vacuum sublimation or recrystallization yielded pure product (0.76 g, 82%). 

Methanol is included to prevent the further reaction of py SO3 with water. The titration s end point is signaled when the solution changes from the yellow color of the products to the brown color of the Karl Fischer reagent. 

Famotidine. Also known as Pepcid, famotidine [76824-35-6] (AT-(aminosulfonyl)-3-([[2-[(diaminomethylene) amino]-4-thia2olyl] methyl]thio)propariimidamide (2) is a white to pale yellow crystalline compound, freely soluble in glacial acetic acid, slightly soluble in methanol, very slightly soluble in water, and practically insoluble in ethanol. It may be prepared by the method described in Reference 3. 

Ranitidine. Ranitidine hydrochloride [66357-59-3] (Zantac) is a white to pale yellow granular substance. It is freely soluble in water and acetic acid, soluble in methanol, sparingly soluble in ethanol, and practically insoluble in chloroform. It has a slightly bitter taste and a sulfur-fike odor. It may be made by the method described in Reference 5. 

Crocin is a yellow-orange glycoside that is freely soluble in hot water, slightly soluble in absolute alcohol, glycerol, and propylene glycol, and insoluble in vegetable oils. Crocin melts with decomposition at about 186°C and has absorption maxima in methanol at about 464 nm and 434 nm. 

Cupric chloride or copper(II) chloride [7447-39 ], CUCI2, is usually prepared by dehydration of the dihydrate at 120°C. The anhydrous product is a dehquescent, monoclinic yellow crystal that forms the blue-green orthohombic, bipyramidal dihydrate in moist air. Both products are available commercially. The dihydrate can be prepared by reaction of copper carbonate, hydroxide, or oxide and hydrochloric acid followed by crystallization. The commercial preparation uses a tower packed with copper. An aqueous solution of copper(II) chloride is circulated through the tower and chlorine gas is sparged into the bottom of the tower to effect oxidation of the copper metal. Hydrochloric acid or hydrogen chloride is used to prevent hydrolysis of the copper(II) (11,12). Copper(II) chloride is very soluble in water and soluble in methanol, ethanol, and acetone. 

This material Is purified by recrystallization from ethyl acetate acetone 2 1 (v v) to give a first crop (6.8 g), and by flash chromatography of the residue from the mother liquor, using 150 g of 230-400 mesh silica gel (Merck), a 40-mm diameter column, and elution with 10 1 (v v) ethyl acetate methanol. A fast moving orange band and a slower moving lemon-yellow band can be clearly seen on the column. The lemon-yellow hand is collected from the column and evaporation gives a second crop (1.4 g) of comparably pure material. The total yield of the pale yellow isoquinoline is 8.2 g (86t), mp 135-137°C (Note 10). 

In a 500-ml. round-bottomed flask equipped with a reflux condenser and a magnetic stirrer (Note 6) are placed 150 ml. of methanol, 150 ml. of 6N hydrochloric acid, and the total yield of 4,4 -bis(acetamido)azobenzene. The mixture is heated under reflux for 1.5 hours. The reaction mixture is cooled and the violet solid collected on a Buchner funnel (Note 7). The damp product is suspended in 500 ml. of water in a 1-1. beaker equipped with a stirrer, and the mixture is slowly neutralized by the addition of 2.5N sodium hydroxide. In the course of the neutralization, the salt dissolves and the free base separates. The 4,4 -diaminoazo-benzene is collected on a Buchner funnel, washed with water, and dried under reduced pressure. The yield of yellow product, m.p. 238-241° (dec.),is ll-12g. The over-all yield from/ -amino-acetanilide is 52-56%. 

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