Behavior with Oxidizing Agents

The cyclitols are resistant to oxidation with dilute nitric acid, but with concentrated acid, depending on the conditions, a variety of products may be obtained ranging from carbon dioxide to cyclic ketones. Reference will be made here, as well as in subsequent sections, to those instances in which the ring has remained intact or in which it has been opened and compounds retaining all the original carbons have been isolated. 

The Scherer test (78) for mi/o-inositol is dependent on the formation of rhodizonic acid (p. 280), whose calcium salt has a red color. This test is 

Posternak moderated the nitric acid oxidation and obtained about a 10% yield of pure DL-epi-inosose-2 (90). This is the racemate of the active form obtained by bacterial oxidation of epi-inositol, which was obtained by reduction of DL-epi-inosose-2 (Fig. 1) (5 a, 76). The oxidation of d-quer-citol to galactaric acid has already been mentioned. 

This oxidation, as employed by Posternak, was very useful in elucidating the configuration of the inositols (see above). From mj/o-inositol, S. and T. Posternak obtained DL-talaric and DL-glucaric acids. From myo-inosose-2, T. Posternak obtained DL-idaric acid. In these instances, the ring was opened to form dibasic acids. d-Quercitol was oxidized by Posternak (6S) to 3-deoxy-D-galactaric acid. In all these oxidations, it was necessary to maintain low temperatures. 

Z-Quinic acid was oxidized to benzoquinone by Wohler (101). Derivatives of conduritol and shikimic acid were hydroxylated at the double bond by Fischer and Dangschat (62, 85). 

---

The same situation is found in the oxidation of certain dissolved reducing agents in many cases these reactions occur only by reaction with oxidizing agents, not on anodic polarization of an electrode. Such behavior is observed primarily in systems with organic reactants, more rarely in systems with inorganic reactants. 

Curing systems using quinoid derivatives (GMF or dibenzo GMF with oxidizing agents) give very fast cures, and they are used on a large scale in the CV wire insulation process aging behavior of these vulcanizates is superior to those obtained by sulfur or sulfur-donor systems. 

Similar results were obtained when carbon was oxidized in liquid medium. Carbon in aqueous suspension is attacked by many oxidizing agents, e.g., permanganate (49-32), chromate (52-54), hypochlorite (52, 55), persulfate (52, 56, 57), and bromate ions (52, 56, 57) chlorine (49), dilute nitric acid (52,58), and concentrated nitric acid (28). The neutralization behavior against the four bases used in Table I was studied with a few samples oxidized in liquid medium (45, 46). The same ratio was observed as with the oxygen-treated carbons, except that twice the amount of groups reacting with sodium bicarbonate was found (Table III). 

Simple 4//-thiopyran (7)5,90,36 or its monosubstituted derivatives7 were oxidized to corresponding thiopyrylium ions of type 221 with several agents. A remarkable difference was observed in the behavior of 7 toward halogens chlorine and iodine caused aromatization, whereas bromine only added to the substrate.361... 

SABATIER, PAUL (1854-1941). A French chemist who received the Nobel prize in Chemistry in 1912 along with Victor Grignard. His work involved the behavior of oxides as oxidizing catalysts and as agents for dehydrating and dehydrogenating. He received his PhD. In Nimes, France, and went on to become lecturer and faculty member in Toulouse, France. 

---