A Little Organic

Even friends who swore off caffeine indulge in a little organic chocolate pick-me-up from time to time. 

V.Z. Kresin and W.A. Little, Organic Superconductivity, Plenum Press, New York, 1990. 

Addition of dilute potassium dichromate(VI) solution, K2Cr207, to a solution of hydrogen peroxide produces chromium peroxide, CrOj, as an unstable blue coloration on adding a little ether and shaking this compound transfers to the organic layer in which it is rather more stable. 

After a little experience in the organic chemistry laboratory, the student will soon find that the yields frequently do not approach the theoretical values. This may be due to one or more of the following causes —... 

Heat a little pseudo-saccharin chloride with excess of the anhydrous alcohol in a test-tube until hydrogen chloride is no longer evolved. Recrystallise from alcohol or other organic solvent. 

Two extractions usually sufiSce, but if much organic material remains, a third extraction should be made. If the p-iodoaniline from the second and third extractions is coloured, it should be refluxed for a short period in light petroleum solution with a little decolourising carbon and filtered through a hot water funnel (CA U TION inflammable). 

Reflux a mixture of 7 3 g. of methyl myristate with a solution of 4 8 g. of sodium hydroxide in 200 ml. of 90 per cent, methanol for 2 hours, distil off the methanol on a water bath, dissolve the residue in 400 ml. of hot water, add 15 ml. of concentrated hydrochloric acid to the solution at 50° in order to precipitate the organic acid, and cool. Collect the acid by suction filtration, wash it with a little water and dry in a vacuum desiccator. The yield of myristic acid (tetradecanoic acid tetradecoic acid), m.p. 57-58°, is 5 9 g. 

The most common interfering substance, especially with alcohols of low mole cular weight, is water this may result in an inaccurate interpretation of the test if applied alone. Most of the water may usually be removed by shaking with a little anhydrous calcium sulphate,. though dry ethers (and also the saturated aliphatic and the simple aromatic hydrocarbons) do not react with sodium, many other classes of organic compounds do. Thus ... 

Strike sees a point to this in Vogel s text Practical Organic Chemistry (3 ed.)[37]. In it, Vogel crystallizes his ketones using a saturated sodium bisulfite solution that a/so contains a little solvent. This is in contrast to the straight up aqueous (only water) solution that Strike described above. Here is A/hat Vogel said on page 342 ... 

X)ml), The reaction mixture was stirred for 24 h. Nearly all of the solvent was removed in vacuo and the residue dissolved in CH2CI2. The solution was washed with 5% NHj, 1N HCl and brine. The organic layer was dried (NajSOJ and the solvent evaporated in vacuo. The residue was purified by chromatography using CHClj-hexane to give the product (28.0 g, 86%) along with a little 3-[2-nitro-2-(indol-3-ylmethyl)ethyl]indole (2.8 g. 5%). 

An organozmc compound that occupies a special niche m organic synthesis is lodo methyhinc iodide (ICH2ZnI) It is prepared by the reaction of zinc-copper couple [Zn(Cu) zinc that has had its surface activated with a little copper] with diiodomethane m diethyl ether... 

To provide a rational framework in terms of which the student can become familiar with these concepts, we shall organize our discussion of the crystal-liquid transition in terms of thermodynamic, kinetic, and structural perspectives. Likewise, we shall discuss the glass-liquid transition in terms of thermodynamic and mechanistic principles. Every now and then, however, to impart a little flavor of the real world, we shall make reference to such complications as the prior history of the sample, which can also play a role in the solid behavior of a polymer. 

Ensuring that the policy is relevant to the expectations and needs of the organization s customers is a little more difficult. Companies need to predict what their customer expectations and needs are (now a requirement in clause 4.1.4 under Business plans). They may be beyond what they specify in contracts although they may in fact be identical to such specifications. For companies to create satisfied customers they not only need to meet requirements specified by the customer but meet national and international legislation and have consideration for the needs and expectations of society. As explained in Part 1 Chapter 1 on Quality characteristics, customers are not only the buyers but comprise several other interested parties. You need to provide a means of determining what the customer expectations and needs are and then subject the written quality policy to a review against those expectations and needs to determine if there is any conflict. As part of your business planning procedure you should indicate how you determine your customer s current and future needs and expectations. 

Traceability is achieved by coding items and their records such that you can trace an item back to the records at any time in its life. The chain can be easily lost if an item goes outside your control. If, for example, you provide an item on loan to a development organization and it is returned some time later, without a certified record of what was done to it, you have no confidence that the item is in fact the same one, unless it has some distinguishing features the inspection history is now invalidated because the operations conducted on the item were not certified. Traceability is only helpful when the chain remains unbroken. It can also be costly to maintain. The system of traceability that you maintain should be carefully thought out so that it is economic. There is little point in maintaining an elaborate traceability system for the once in a lifetime event when you need it, unless your very survival, or society s survival, depends upon it. 

The reaction mixture is diluted with 250 ml of water, the mixture is transferred to a 2 liter flask using methanol as a wash liquid, and the organic solvents are distilled at 20-25 mm using a rotary vacuum evaporator. The product separates as a solid and distillation is continued until most of the residual toluene has been removed. The solid is collected on a 90 cm, medium porosity, fritted glass Buchner funnel and washed well with cold water. After the material has been sucked dry, it is covered with a little cold methanol, the mixture is stirred to break up lumps, and the slurry is kept for 5 min. The vacuum is reapplied, the solid is rinsed with a little methanol followed by ether, and the material is air-dried to give 9.1 g (85%), mp 207-213° after sintering at ca. 198°. Reported mp 212-213°. The crude material contains 1.0-1.5% of unreduced starting material as shown by the UV spectrum. Further purification may be effected by crystallization from methanol. 

Androst-4-ene-3,17-dione. Testosterone (0.58 g, 2 mmoles) is dissolved in a solution prepared from 3 ml of benzene, 3 ml of dimethyl sulfoxide, 0.16 ml (2 mmoles) of pyridine and 0.08 ml (1 mmole) of trifluoroacetic acid. After addition of 1.24 g (6 mmoles) of dicyclohexylcarbodiimide, the sealed reaction flask is kept overnight at room temperature. Ether (50 ml) is added followed by a solution of 0.54 g (6 mmoles) of oxalic acid in 5 ml of methanol. After gas evolution has ceased ( 30 min) 50 ml of water is added and the insoluble dicyclohexylurea is removed by filtration. The organic phase is then extracted twice with 5 % sodium bicarbonate and once with water, dried over sodium sulfate and evaporated to a crystalline residue (0.80 g) which still contains a little dicyclohexylurea. Direct crystallization from 5 ml of ethanol gives androst-4-ene-3,17-dione (0.53 g, 92%) in two crops, mp 169-170°. 

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