Needles deposition

To nickel powder (5.0 g, 85.2 mmol) in a 250-mL, round-bottomed flask equipped with a reflux condenser is added p-toluenesulfonic acid monohydrate (32.23 g, 169 mmol) and water (20 mL). The mixture is heated to reflux for 15 h after this time, some metal powder remains. The green mixture is filtered while hot through Celite and the filter cake washed with water (3 x 10 mL). The filtrate is cooled to room temperature, and large green needles deposit on standing. The crystals are collected by filtration and dried overnight under vacuum at... 

A solution of 2,3-dimethylindole (145 g, 1 mol) in dry dioxan containing hydroquinone (100 mg) was treated with JV,JV,JV-trimethylbenzylammonium ethoxide (5 ml of a 40% solution in MeOH) and warmed to 35 C. Freshly distilled acrylonitrile (150 ml, 2.5 mol) was added at a rate such that the temperature did not rise above 40°C. The solution was then stirred overnight and diluted with 10% aq. acetic acid (11). The solution was extracted with CH Clj and the extract was washed with water and dried (MgS04). extract was then mixed with silica gel (800 g) and the solvent removed in vacuo. The silica was placed in a Soxhlet extractor and extracted with cyclohexane. The extract deposited the product as colourless needles (125 g, 63% yield). 

In the spunbond process, the fiber is spun similarly to conventional melt spinning, but the fibers are attenuated by air drag appHed at a distance from the spinneret. This allows a reasonably high level of filament orientation to be developed. The fibers are directly deposited onto a moving conveyor belt as a web of continuous randomly oriented filaments. As with meltblown webs, the fibers are usually thermal bonded or needled (53). 

The benzene solution is separated and washed twice with 100 cc. of water, once with 200 cc. of 5 per cent potassium hydroxide, and twice with water, and in case the solution is not colorless it is clarified with i g. of Norite. The benzene is removed by distillation and the resulting syrup is dissolved in 300 cc. of alcohol by heating. The solution on cooling deposits cholestanone as well-formed needles. The yield of collected, washed, and air-dried material, m.p. 129-130°, is 41.5-42 g. (83-84 per cent of the theoretical amount). The addition of 80 cc. of water to the filtrate gives about 2 g. of material melting at 125-126°. 

Tyrosine.—On cooling, a brown, crystalline crust of impure tyrosine separates. It is filtered, dissolved in the least quantity of boiling water, boiled with a little animal charcoal, and filtered. Oit cooling, long, white, silky needles of tyrosine arc deposited. Yield. rborit 2 grams. 

Acetylation of Kasuganobiosamine (4). Acetic anhydride (2 ml.) and pyridine (4 ml.) were added to kasuganobiosamine (212 mg., 0.688 mmole) and the solution was allowed to stand at room temperature for 24 hours. The reaction mixture was treated with ice-water and extracted three times with chloroform. The organic layer was dried over sodium sulfate. After removal of the solvent, an oily material was treated with 30 ml. of ether to deposit a crystalline material. It was further recrystallized from ether-ethyl alcohol to afford a needle crystalline material (409 mg., 0.679 mmole), m.p. 242°-243°C., and identified to be heptaacetate of 4. Anal Calcd. for C26H38014N2 C, 51.58 H, 6.44 O, 36.69 N, 4.41. Found C, 51.27 H, 6.44 O, 36.42 N, 4.53. 

Introduce a 0.30 pL portion of the solvent extract into the gas chromatograph. It is found that solutions of concentrations greater than 0.3 M are unsuitable as they deposit solid and thus cause a blockage of the 1 jj.L microsyringe used for the injection of the sample. The syringe is flushed several times with the sample solution, filled with the sample to the required volume, excess liquid wiped from the tip of the needle and the sample injected into the chromatograph. 

To a solution of l-(4-methoxyphenyl)-biguanide (2.07 g, 10 mmol) and l-(4-methoxyphenyl)-biguanide hydrochloride (0.2 g, 1 mmol) in EtOH (50 mL) was added 1-benzoylacetone (1.62 g, 10 mmol) and the solution was heated under reflux for 10 h. After the solution was concentrated, the oily residue was poured into H20 and repeatedly washed with H20. The resulting solidified mass was collected by filtration and dissolved in EtOH by heating. After standing overnight at rt, a mixture of needles and prisms was isolated yield 1.5 g (45%). The mixture was dissolved in a suitable amount of EtOH by heating and, after 2 h at rt, the deposited, needles were collected by filtration mp 166 C. The needles were dissolved in a suitable amount of EtOH and the solution was left to stand at rt for a couple of days. The deposited prisms were collected by filtration mp 166°C. 

N 36.83%, OB to C02 -42.1% colorless needles from ether nip 38° d 1.243 at 49/4° RI 1.4616 at 48,6°. V sol in cold w, ale, chlf and benz less sol in eth and still less sol in petr eth. Can be prepd by nitrating n-methyl-urethane with abs nitric acid. The resulting soln of methyl nitrourethane is drowned in w, neutralized with Na carbonate, and extrd with eth to remove methyl nitrourethane. On passing ammonia gas thru the eth extract, a white ppt of the ammonium salt of methylnitramine is deposited and sepd by filtration. It is disd in ale and boiled to drive off the ammonia, and... 

Sulfates typically are found as a hard, dense, white deposit (occasionally in a thin, needle-like crystal form) of anhydrite (CaS04). 

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