Polytetramethylene Sebacate: Pyrophoric Lead as an Ester

C. S. Marvel, and John H. Johnson. J. Am. Chem. Soc. , 1950, 72 (1), pp 624–624. DOI: 10.1021/ja01157a504. Publication Date: January 1950. ACS Legac...
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atom concerned has the a-configuration. In an appeared to be finely divided lead. As a result, a-D-fructopyranose the 2-OH is in the a-orienta- pyrophoric leada was tried as a catalyst in this tion and the 2-CMzOH in the /3-orientation. The interchange reaction and found to work well. carbon centers in a-D-glucose, as shown in formula The use of a wide variety of finely divided metals as catalysts for the preparation of polyethylene I, are: la, ~ L Y 3/3,4a, , 5/3. In the Fischer-Rosanoff system of nomen- terephthalate from ethylene glycol and dimethyl clature as defined by Hudson,Gthe enantiomer of terephthalate has been describedSbut no mention a-D-glucose of formula I1 is called a-L-glucose, was made of pyrophoric lead. but the true meaning is conveyed more accurately The polyesters were prepared in an apparatus similar by the designation ''a''-L-glucose, for the prefix to that described by Hardy4 from 11.8 g. of dimethyl is used merely in a trivial sense and does not bear sebacate and 5.0 g. of butane-1,4-diol. The charges were with the 0.1 g. of catalyst under varying conditions the connotation of configuration. Since the heated and then the polyesters were purified by solution in chloroactual configurations are established with cer- form, atration and reprecipitation with acetone. The tainty, it would seem rational to abandon the following cases seem sufficient to indicate that pyrophoric trivial designations in favor of prefixes that have lead is a satisfactory catalyst in this type of reaction. The are essentially quantitative. configurational significance. The enantiomer of yields Run No. 1 : 0.1 g. of litharge as catalyst; reaction mixa-D-glucose is the exact optical opposite at all ture heated for two hours a t 183" and atmospheric prescenters, including CI, and is properly described as : sure, then for one hour at 259" and 0.1 mm. pressure. The polymer was isolated and the intrinsic viscosity taken 18, 2/39 3%4/39 5a. 0.401, solution in chloroform a t 25.5"; [9]0.61. The proposed system can be distinguished from in Run No. 2 : Same catalyst as No. 1 ; reaction mixture that in current use by including in the name a heated three hours a t 155" and atmospheric pressure and number indicating the carbon atom whose con- one hour a t 155" and 0.03 mm. pressure; [s] 0.33. figuration is defined by a or /3. Thus I is k - ~ - Run No. 3 : 0.1 g. of pyrophoric lead; reaction mixture two hours a t 172" and atmospheric pressure and glucose (or la-D-glucopyranose); I1 is l@-L-glu- heated six hours longer a t 1mm; [7]0.98. cose; methyl a-D-fructopyranoside is more speciRun No. 4: Same catalyst as No. 3 ; reaction mixture fically described as methyl 2a-D-fructopyranoside. heated three hours a t 172" and atmospheric pressure, then For purposes of discussion it may be convenient to three hours a t 0.1 mm.; [VI 0.55. Anal. Calcd. for C14Ht404:C, 65.60; H , 9.44. Found: state that 1a-D-mannopyranoseis the 2P-epimer of 1a-D-glucopyranose, or that methyl 1a-L-idopyra- C, 65.45; H, 9.63. The polyesters obtained with pyrophoric lead were noside is the 5a-epimer of methyl 1a-D-glucopyra- whiter than those from the litharge runs. The polymers all noside. The important relationship discovered by melted at 64-64.5'. Hudson' can be so stated that one rule is applicable (2) King, "Inorganic Preparations," D. Van Nostrand Company, to all types of cyclic sugars of both the D- and L- New York, N . Y., 1936, p. 24. series: in a pair of glycosidic epimers, the isomer 13) British Patent, 578,079. with the glycosidic hydroxyl or alkoxy1 group in (4) Hardy, J . Soc. Chem. I n d . , 67, 426 (1948) the a-orientation is invariably more dextro- NOYESCHEMICAL LABORATORY rotatory than the $-epimer. X relationship UNIVERSITY O F ILLINOIS RECEIVED SEPTEMBER 19, 1949 ILLINOIS discovered by Isbel17 can be stated as follows: URBANA, a la-D-pyranose, in which C1 and Cg are a and p, respectively, or trans, is oxidized much more slowly than the 1/3-epimer in which they are /3 Preparation of Naphthyl Acid Phosphates' and p , or c h . (6) C. S. Hudson, ' Historical Aspects of Em1 Flscher's Fundamental Conventions for Writing Stereo-Formulab in a Plane '' A d e i n Carbohydrate Chem , 8, 1 (1948). (7) H S. Isbell, J . Research Null Bur Standards, 18,505 (1937). KP 990: H S. Isbell and W \\'. Pigman. ibzd , 18 141 (1937) RP 969, H S Isbell, J Chciri Edilc 12, 96 (19353

H ~ V A RUNIVERSITY D CAMBIUDGE 38, MASS

RECEIVED OCTOBER 8, 1949

Polytetramethylene Sebacate: Pyrophoric Lead as an Ester Interchange Catalyst BY C. S. MARVEL* AND JOHNH.

JOHNSOX~

In preparing polytetramethylene sebacate from butaae-1,4-diol and dimethyl sebacate with a litharge catalyst, one run gave a better grade of polyester than had been obtained before. In this polyester sample there was a black deposit that

* Editorial Board 1945(1) Allied Chemical and Uyr Corporation Fellow, 1948-1949

BY

ORRIE

XI. FRIEDMAN* AND

.kNOLD

h l . SELICMANI

Methods for the histochemical demonstration of alkaline phosphatase3 and acid phosphatase3 have been developed utilizing as substrates the calcium salts of a- and &naphthyl acid phosphates. Following enzymatic hydrolysis of these substrates, coupling with a suitable diazonium compound, results in the deposition of an insoluble azo dye at the site of enzymatic activity. Although the calcium salts of these phosphoric esters are readily prepared2* their poor solubility in water requires their use in a fine suspension for * Harvard University Research Fellow, Chemistry Department, 1946-1949. t Harvard Upiversity Assistant Professor of Surgery, Medical School. (1) This investigation was supported by a research grant from the National Cancer Institute of the National Institutes of Health, Public Health Service. (2) (a) Menten, Junge and Green, J . Bid. Chem., 168, 471 (1944). (b) Manheimer and Selipman, J . .Vat. Cancer I n s t i t , 9, 181 (1948). (3) Sdigman and Manheimer, ibid., 9, 427 (1949)