Notes 2777 Experimental General.-Melting points were taken in an open capillary tube and are corrected. The ultraviolet spectra were determined in methanol on a Cary recording spectrophotometer and infrared spectra (pressed potassium bromide disks) were carried out with a Perkin-Elmer spectrophotometer (Model 21). N.m.r. data were determined with tetramethylsilane as an internal standard in deuteriochloroform with a Varían Model DP-60 spectrometer at 56.4 Me. All evaporations were carried out under reduced pressure, and the petroleum ether used was that fraction boiling at 60-70°. Nitrogen analyses were by the Dumas method.16/3-Cyano-3-methoxy-16a-methylestra-l ,3,5(10 )-trien-17-one (II) .-To a solution of 500 mg. of 16-cyano-3-methoxyestral, 3,5( 10)-trien-17-one6 (I) in 25 ml. of reagent acetone, through which nitrogen was bubbled, was added 1 g. of anhydrous potassium carbonate and 2 ml. of methyl iodide. The mixture was allowed to stir under a nitrogen atmosphere for 2 days after which time another 2 ml. of methyl iodide was added and stirring was continued for an additional 5 days. The mixture then was filtered and the mother liquor was evaporated to dryness. The residue was recrystallized from acetone-water to give 442 mg. (85%) of product, m.p. 173-176°. Recrystallization from acetone-petroleum ether and then from ether-petroleum ether gave white crystals, m.p. 185-186°; [<*]26d +108°(c 0.58, CHCh);
5.64X10-6 c.g.s.-e.m.u., 3.2 B.AII.; (Ph3P)ZNiBrz tert. BuBr, 5.37X1OP6, 3.4 B.i\lI.; and (Ph3P)?NiBr?(PhBr)z, 5.59XlOw6, 3.8 B.M. The high magnetic moment of the Ni2+ ion in the latter two suggests that distortion from a regular tetrahedral arrangement can be decreased by the presence of crystalline solvent. The distortion in the coinpounds (Ph3P)?NiX2 ( X = Cl, Br, I, and NO3) seems to be partially due to the steric requirement by the size difference between triphenylphosphine and halide ion. T o compensate for such a steric effect in (Ph3P)?NiBrz two inolecules of brolnobenzene may be more suitable than one molecule of tert.butyl bromide. The appearance of blue tint in many cases of compounds of the types (Ph3P)ZNiXzY and (Ph3P)?NiX?Y2 may have soine correlation with rather sinall distortion from a regular tetrahedral arrangement.The author wishes to thank Professor H. Akainatu for his interest in this worlc and also the Mitsui Chemical Industry Company for the gift of the samples studied here.1. N. S. GILL, R. S. NYHOLM, and P. PAULING. Nature, 182, 168 (1958 CRYSTALLINE GLYOXYLIC ACID AND ITS SODIUM-CALCIUM SALTEarly researches 011 the preparation and properties of glyoxylic acid were extensively reviewed by Debus (1) and by Hendriclcs (2), who noted that the substailce occasionally yielded ill-defined rhombic crystals of a monohydrate when stored over a drying agent. I n 1925, Hatcher and Holden (3) used the electrochemical method to reduce oxalic acid, isolated barium glyoxylate, decomposed the latter with sulphuric acid, and prepared anhydrous glyoxylic acid for the first time as monoclinic crystals melting a t 98'. This result was questioned by He[~clriclcs (2) because oxalic acid monohydrate, a probable impurity, melted a t 99' and occurred as monoclinic crystals, and also because his attempts to repeat the crystallization of glyoxylic acid failed. Later workers oxidized tartaric acid or its esters with a glycol-cleaving agent, periodic acid or a periodate (4, 5, 6), lead tetraacetate (7), or sodiuln perbismuthate (S, 9), but apparently restricted their interest to the preparation of various esters and metallic salts of glyoxylic acid.In the present worlc, tartaric acid was oxidized with aqueous periodic acid, by-product iodic acid was removed as the insoluble lead salt, and, after neutralization with barium hydroxide, crystalline barium glyoxylate dihydrate was recovered in high yield. A11 ionexchange resin eliminated the cations fro111 an aqueous solution ol this salt, and evaporation of the effluent left glyoxylic acid as a clear syrup which eventually crystallized. The lnelting point was 104-107°, with softening a t 94'. The replacement of periodic acid by sodium inetaperiodate in the above oxiclation, followed by the removal of iodate ion, left
A B S T R A C T T h e starch was oxidized withThe oxidation of various species of starch with alkaline hypochlorite, a process of industrial as well as academic interest, has been studied for many years. Reviews (1, 2) of the subject show that most of the early interest was attracted to the changes produced by various amounts of oxidant in such properties as viscosity and copper-reducing power, ease of retrogradation, and the adsorption of dyes. Degradation products were isolated and identified in only a very few instances. McKillican and Purves (3) more recently obtained evidence that hypochlorous acid near pH 4 oxidized wheat starch in the second and sixth positions of the glucose residues to yield in part 2-lteto and uronic acid derivatives. Whistler and his collaborators (4, 5), employing corn amylose and ainylopectin with hypochlorite kept a t 25" and a t various pIH values between 3 and 13, dialyzed the products and showed that both the dialyzable and the non-dialyzable portions yielded D-glucose, glyoxylic acid, D-erythronic acid, and D-erythronolactone after hydrolysis with acid. Oxidations near pH 7 produced the maximum amount (about 0.3 mole) of glyoxylic acid. The present research provided additional information about the course of the reaction a t pH 12 and 20".Preliminary experiments, employing 0.12 M and 0.06 M calcium hypochlorite with illole ratios per CsH1005 unit of 1: 1 or 1 :0.5, confirmed the observation (5) that such oxidations were exceedingly slow. Sodium hypochlorite yielded solutions from which it was more difficult to isolate the organic products. The use of a greater excess (mole ratio, 5.5:l) of a more coilcentrated (0.43 M ) hypochlorite increased the speed of the oxidatioil to a convenient value, and had the additional advantage that the rate coilstant for the disappearance of hypochlorite would tend to follow the first-order ltinetic equation. A semilogarithmic plot of the data (Fig. l , plot A) became linear after about 76 hours and could be represented by the equation log 0.24/(0.24 -b) = 2.2 X 10-3T, where b was the concentration of hypochlorite consumed a t time T, the units being moles, liters, and hours. Substitution of values of T between zero and 76 hours then yielded values of b froin which, by difference froin the observed values, the corresponding data bl for the initial, fast reaction could be calculated. These data (plot B) also fitted a first-order equation, log 0.19/(0.19 -bl) = 2 . 2 f 0.1 X lo-? T.The above calculatioils suggested that the oxidatioil of starch with hypochlorite a t pH 12 consisted of a relatively rapid reaction consuming 2.34 moles of l~ypocl~lorite
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