Of polyhydric alcohols

Some characteristic reactions of polyhydric alcohols are given below ... 

Benzoates. The preparation of benzoates of polyhydric alcohols may be illustrated by reference to glycerol. They are usually crystaUine solids. 

Polyesters from polybasic acids and polyhydric alcohols. Alkyd resins. The condensation of polyhydric alcohols and polybasic acids or anhydrides leads to polj esters known as alkyd resins. The most common member of the group is a glycerol - phthahc acid polymer, and this has led to the term glyptal resins being frequently apphed to the whole group. 

Heteroatom functionalized terpene resins are also utilized in hot melt adhesive and ink appHcations. Diels-Alder reaction of terpenic dienes or trienes with acrylates, methacrylates, or other a, P-unsaturated esters of polyhydric alcohols has been shown to yield resins with superior pressure sensitive adhesive properties relative to petroleum and unmodified polyterpene resins (107). Limonene—phenol resins, produced by the BF etherate-catalyzed condensation of 1.4—2.0 moles of limonene with 1.0 mole of phenol have been shown to impart improved tack, elongation, and tensile strength to ethylene—vinyl acetate and ethylene—methyl acrylate-based hot melt adhesive systems (108). Terpene polyol ethers have been shown to be particularly effective tackifiers in pressure sensitive adhesive appHcations (109). 

Transparent dentifrices can be prepared from certain xerogel siUcas through use of high levels of polyhydric alcohols. Clarity depends on matching the refractive indexes of the siUca and the Hquid base. Compositions for Hquid facial cleansers (68), shampoos (69), conditioning shampoos (70), dandmff shampoos (71), surfactant bars (72), toothpastes (73), and mouthwashes (74) have been pubUshed. 

Epichlorhydrin.—It is a noteworthy fact that althoug-h hydiochloric acid can leplace hydroxyl by chlorine in the case of the monohydric alcohols, the number of hydroxyl groups which are substituted in the case of polyhydric alcohols is strictly limited. Like glyceiol, ethylene glycol gives a chlorhydrin, CIi..OH.CILOII 1- IICl CHnOH.CILCl -1- ILO. 

Hawley, Glossary of Chemical Terms , Van-Nostrand-Reinhold,NY (1976), 217 Addnl Refs 1) K.S. Warren, Study Nitrates of Polyhydric Alcohols as Explosives , PATR 1103 (1941) la) D.B. Bright et al, Development of Polyol Prepolymers Containing High Energy Oxidizing Groups , Report No S-13843, Contract AF 04(611>5690, Shed Devel Co, Emeryville (1961) (limited distribution) 2) A.D. McElroy, Basic Approach to Incorporation of NP Propellants , Rept No RPL TDR 6448, Contract AF 04(611)-9059, Callery Chem Co, Phlla (1964) 3)... 

Besides these normal technical products, many other different types of a-sulfo fatty acid esters have been described in the literature. For example, Weil et al. prepared a-sulfopalmitates and stearates with higher alcohols [19] and also monoesters of polyhydric alcohol [39] and of hexitols and sucrose [40] for their special properties. In addition to the sodium salt, Stirton et al. used other cations, such as Li, NH4, K, Mg, and Ca, to study the relationship between the structure and the surfactant properties [30]. 

CARBOHYDRATES ARE ALDEHYDE OR KETONE DERIVATIVES OF POLYHYDRIC ALCOHOLS... 

Hamelin A, Ho Y, Chang SC, Gao X, Weaver MJ. 1992. Surface crystallographic dependence of voltammetric oxidation of polyhydric alcohols and related systems at monocrystaUine gold-acidic aqueous interfaces. Langmuir 8 975-981. 

The system is not limited to the use of synthesis gas as feed. Mixtures of carbon dioxide and hydrogen also give rise to the formation of polyhydric alcohols, and it is also claimed that the reaction mixture can consist of steam and carbon monoxide (62). This latter claim is consistent with the presence of C02 in the reaction mixture when CO/H2 is used as feed [infrared data (62)], and suggests that these ionic rhodium systems are also active catalysts for the water gas-shift reaction (vide infra). 

W15. Williams-Ashman, H. G., Banks, J., and Wolfson, S. K., Jr., Oxidation of polyhydric alcohols by the prostate gland and seminal vesicle. Arch. Biochem. Biophys. 72, 485-494 (1957). 

Although the polyhydric alcohols derived from sugars have been the subject of numerous investigations over many years, the inner ethers or anhydrides of these substances have been for the most part neglected, despite the fact that many of them were isolated and some description of their properties recorded before the advent of the twentieth century. In recent years, however, the anhydrides of polyhydric alcohols derived from sugars have received marked attention in several countries. Some indeed have achieved importance in chemical industry. Most interest has been centered on the anhydrides of pentitols and hexitols and this article will be restricted to a discussion of the chemistry of these substances. 

The formation of anhydro-glycitols and the investigation of their structure and that of the products of their ring scission provide fascinating problems in structural organic chemistry and this structural aspect of the chemistry of anhydrides of polyhydric alcohols forms the mainstay of this article. 

The electrochemical oxidation of polyhydric alcohols, viz. ethylene glycol, glycerol, meso-erythritol, xilitol, on a platinum electrode show high reactivity in alkaline solutions of KOH and K2C03 [53]. This electro-oxidation shows structural effects, Pt(lll) being the most active orientation. This results from different adsorption interactions of glycerol with the crystal planes [59]. 

Prominent co-catalysts for the Pt-on-carbon anode catalyst in the oxidation of polyhydric alcohols are Ru or Ce02 [54, 60]. Their increased resistance to poisoning with mainly CO during operation is associated with the existence of a bifunctional mechanism (Scheme 11.6). 

Bulk separation of polyhydric alcohols by selective adsorption on... 

The direct separation of polyhydric alcohols does not appear to have been used in polysaccharide structural studies, except in the case of the methylated compounds that will be discussed in Part II of this article. 

Separations of polyhydric alcohols by gas-liquid chromatography are of interest in fields other than carbohydrate chemistry, and it is convenient to make brief mention of some of these applications. Several references to the separation of polyhydric compounds without the formation of derivatives are given in the paper by Verachtert,473 and similar methods related to the separation of acyclic and alicyclic diols,617 to the separation of a series of a,(u-diols,818 to the analysis of ethylene glycol, methanol, and diethylene glycol,819 and to the an-... 

An article on the anhydrides of polyhydric alcohols appeared in Volume 5 of this Series,1 and it is the purpose of the present article to bring the subject up to date. Wiggins article1 was limited to the anhydrides of the pentitols and hexitols the present article will include the anhydrides of tetritols and of alditols higher than the hexitols. However, anhydrides having the three-membered (oxirane) ring will not be considered, as they are discussed elsewhere in this Volume.13 2,5-Anhydrides of aldoses are also treated in this Volume.lb... 

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