Diol A compound containing two

The acetals you have met so far were formed by reaction of two molecules of alcohol with one of carbonyl compound. Cyclic acetals, formed by reaction of a single molecule of a diol, a compound containing two hydroxyl groups, are also important. When the diol is ethylene glycol (as in this example) the five-membered cyclic acetal is known as a dioxolane. 

In the lUPAC system, a compound containing two hydroxyl groups is named as a diol, one containing three hydroxyl groups as a triol, and so on. In lUPAC names for diols, triols, and so on, the final -e (the suffix) of the parent alkane name is retained. 

Diol (Section 10.1 B) A compound containing two hydroxyl groups. 

Polyurethanes are manufactured by the reaction of diisocyanates with diols, diamines, or other organic compounds containing two or more active hydrogens. The reaction rate between a diisocyanate and alcohols catalyzed with dibutyltin dilaurate yielding urethanes was studied by G. Borkent and J. J. Van Aartsen. 

Compounds of type XXV have been obtained by the reaction of Ph As(0Me)5- (n = 2 or 3) with a diol. It has been observed that compounds containing two rings are thermodynamically more stable than compounds with one ring. This is independent of ring size. 

A compound containing an oxygen atom bonded to two alkyl or aryl groups, (p. 500) Synonymous with diol. The term glycol is most commonly applied to the 1,2-diols, also called vicinal diols. (p. 496)... 

Diol A compound that contains two hydroxyl groups, usually on different carbons, e.g. a vicinal diol such as HOCH2-CH2OH. If the diol is geminal, then it is called a hydrate. 

Since it is symmetrical, having identical alkyl groups, preparation by dehydration of an alcohol is efficient. Also, since the compound contains two oxygens, a compound with two hydroxyl groups as the main functional groups, a diol, must have been used. The dihydroxy compound having two carbons is called ethylene glycol, HO-CHaCHa-OH. The reaction is shown below. 

Much of the chemistry of diols—compounds that bear- two hydroxyl groups—is analogous to that of alcohols. Diols may be prepared, for example, from compounds that contain two carbonyl groups, using the same reducing agents employed in the preparation of alcohols. The following example shows the conversion of a dialdehyde to a diol by... 

The reactions of the six-membered chlorocyclophosphazene were studied with a number of aliphatic diamines (169 175), aromatic diamines (176), aliphatic diols (177-179), aromatic diols (180,181) and compounds containing amino and hydroxyl functional groups (169,170,182). This subject has been reviewed (11,16,20). There are at least five different reaction products that are possible (Fig. 19). Replacement of two chlorine atoms from the same phosphorus atom produces a spirocyclic product. Replacement of two chlorine atoms from two different phosphorus atoms in the same molecule produces an ansa product. Reaction of only one end of the difunctional reagent, resulting in the substitution of only one chlorine atom, leads to an open-chain compound. Intermolecular bridged compounds are formed when the difunc-... 

The two five-membered rings of this spirocyclic X. Si-silicon(IV) complex each contain two oxygen atoms, one nitrogen atom, one carbon atom, and one (pentacordinate) silicon atom. As shown in Scheme 8, this compound was prepared by analogy to the synthesis of the related A, Si-silicates 10-16. Thus, treatment of (MeO)3SiCH2NMe2 with two mole equivalents of acetohydroxamic acid in acetonitrile at room temperature yielded 28 in 80 % yield as a crystalline solid [5]. The formation of this compound can be understood in terms of a reaction of (MeO)3SiCH2NMe2 with the 1,2-diol acetohydroximic acid, which is a tautomer of acetohydroxamic acid. 

Simultaneous oxidation of two alcohol functionalities can be performed in both saturated and unsaturated compounds. For example, oxidation of diol 24 was achieved in 30% yield to give diketone 25.33 Steric factors can play a large effect and can result in other reaction processes, such as rearrangement.3 Oxidation of saturated steroid 26 (R = C6H11O2) furnishes diketone 27, with inversion taking place at C-5,39 whereas oxidation of unsaturated steroid 28 (R = C8H17) also yields diketone 27, in which the double bond has been formally reduced.40 The oxidation of steroids containing two cis alcohols at the C-3 and C-5 positions is hindered by the formation of an unreactive aluminum chelate.41... 

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