The family silver To avoid crippling confusion in motivation, one stoutly reaffirms the belief of ages past that one is in business for the money. Today, however, other motivators exhibit their power, and though we still pursue the almighty dollar fiercely, once we have caught it we give little thought to the promise printed on it under President Washington's portrait. It promises silver. Our corporate father's house is founded on this truly unique gem of the periodic table. The marvelous behavior of the crystal lattice that it forms with bromine, when properly studded with impurities, makes photography possible; the importance of photography in both the serious and the gay is a major component of the force that attracted over 109 almighty dollars into our father's till last year. (Figuratively. Physically, they are only a configuration of magnetized domains on a strip of iron oxide in some vault. Wonderful is the mind of man.) Silver is drawn from the vault (a different vault) and made into pure AgN03. The vast bulk of this gets converted to silver halides and moves out on photographic goods. A very few parts per million find their way into bottles labeled "KODAK Silver Nitrate," which can be ordered only from Kodak photographic dealers. Now AgN03 can also be ordered as EASTMAN 491 along with EASTMAN Organic Chemicals (which, not being photographic merchandise, are not handled by photographic merchants). Silver nitrate, of course, has been a fixture of the chemical laboratory since long before the invention of the test tube. It still makes news. Only last spring it was revealed that silica impregnated with AgN03 displays highly
selective adsorption with respect to the geometry and number of C = C ' s in related unsaturated lipids, as detailed for chromatographic practice in Chemistry and Industry\ June 16 and July 7, 1962. Last year also, AgN03-Dichromate spray reagent was proposed for mercapturic acids and S-phenylcysteines (J.C.S., 1962, 608). AgN03 paper detects and fixes volatile As and Sb hydrides (Chim. Anal., 43, 441). AgN03 is needed in the complexometric titration of K, Li, and Rb (Mikrochim. Acta, 1961, 644, 729, 732). Ol' AgN03 is still going very strong. It is one of the few soluble silver salts. AgBr dissolves in water only to the extent of .00002g./100g. Agl and AgCl (but most emphatically not AgF) are similarly lower in solubility than merely poorly soluble silver compounds. An ion switch that produces one of these three will therefore pull through to completion. With appreciation for this simple fact, we offer: Silver Nitrite* (watch the spelling and call it EASTMAN 8671) to make certain nitroparaffins and nitroesters from halides, viz. A g N 0 2 + RX -+ R N 0 2 + A g X ! {J.A.C.S., 76, 3209) Silver Arsenate (EASTMAN 8791) for bringing arsenic into organic chemistry by the reaction Ag 3 As0 4 + 3RI -+ (RO) 3 As = 0 + 3 Agl I Silver Carbonate (EASTMAN 8777) for bringing carbonate into organic chemistry, e.g. (R 4 N) 2 C0 3 Acetic Acid Silver Salt (EASTMAN 8727, and aren't we silly in our nomenclature!) to make quaternary acetates** by similar metathesis Silver Cyanate (EASTMAN 1948) for introducing a cyanate radical and then arguing about the distinction between OCN" and NCOp-Toluenesulfonic Acid Silver Salt (EASTMAN 7912, "silver tosylate") which reacts with a primary aliphatic halide to "precipitate the silver halide and yield the aliphatic tosylate, which, when added to a suspension of NaHC03 in Methyl Sulfoxide (EASTMAN P7108) at 150°C, loses its tosyl and leaves CH 3 (CH 2 ) n -iCHO from what started out as CH3(CH2)nX. We also ought to say something about reagents for silver, starting with the good old 5-{p-Dimethylaminobenzylidene)rhodamine (EASTMAN 2748) and that specialty of the house, Diphenylthiocarba-
zone (EASTMAN 3092), wherein both the N a n d the S retain their individual affinities for various metals. Readers with good enough connections into Belgrade to snaggle the October '61 Bulletin of the Institute of Nuclear Sciences "Boris Kidrich" can continue the stimulating investigation of the behavior of silver in a sulfur environment such as provided by the proposed analytical reagent l-Phenyl-2-tetrazoline-5-thione (EASTMAN 5220). We also have its salt, l-Phenyl-lH-tetrazole-5-thiol Sodium Salt (EASTMAN 8602).
Then there is a middle ground explored in Talanta, 8, 711 and Anal. Chim. Acta, 27, 9 where favor for spectrophotometric determination of Ag is awarded to Pyrogallol Red (Pyrogallolsulfonephthalein, EASTMAN 7655) and Bromopyrogallol Red (Dibromopyrogallolsulfonephthalein, EASTMAN 7704).
The silver thread also leads into the brain itself, although a bit circuitously. In fooling around with certain silver phosphonates, we generated some high-quality Phenyl Phosphorochloridate ( which went on the shelf as EASTMAN 8374) and Phenyl Phosphorodichloridate (EASTMAN 8764). From Toronto, across Lake Ontario from us, has issued for years a stream of publications on these compounds as phosphorylating agents. In J.A.C.S., 72, 944 is told how to use the dichloridate to synthesize individual lecithins of desired configuration to help elucidate the function of lecithin in nature. In J.A.C.S., 74, 152 the same compound makes enantiomeric a-cephalins, those diacylglycerylphosphoryl ethanolamines that were first obtained from the human brain (literally) 30 years ago in Tokyo and which were later shown to be the acid-resistant stain receptors in tubercle bacilli. In J.A.C.S., 75, 4510, the dichloridate makes a-glycerylphosphorylethanolamines and this suggests certain insights into the carbohydrate cycle. And from Biochemical Preparations, I, 50 one learns to use the monochloridate to prepare the dihydrate calcium salt of DL-glyceraldehyde-3-phosphoric acid for study of the metabolism of that compound. Some 4000 other EASTMAN Organic Chemicals which have practically nothing to do with silver can also be ordered from List No. 43, issued by Distillation Products Industries, Rochester 3, N. Y. (Division of Eastman Kodak Company). Additional literature references on request.
* Also useful in preparing a Pt coordination compound (J. Inorg. Nucl. Chem., 22, 2 44). ** If thinking of them as supporting electrolytes for polarography, permit us to call your attention also to ready-made Tetraethylammonium Perchlorate (EASTMAN 8617) {Inorg. Chem. 1, 196).
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