Epichlorohydrin, reaction with

The boric and sulfuric acids are recycled to a HBF solution by reaction with CaF2. As a strong acid, fluoroboric acid is frequently used as an acid catalyst, eg, in synthesizing mixed polyol esters (29). This process provides an inexpensive route to confectioner s hard-butter compositions which are substitutes for cocoa butter in chocolate candies (see Chocolate and cocoa). Epichlorohydrin is polymerized in the presence of HBF for eventual conversion to polyglycidyl ethers (30) (see Chlorohydrins). A more concentrated solution, 61—71% HBF, catalyzes the addition of CO and water to olefins under pressure to form neo acids (31) (see Carboxylic acids). 

One of the first attempts to produce polyurethane was from the reaction of an intermediate polyol of 1,3- and l,4-bis(hydroxyhexa uoroisopropyl)benzene m- and -12F-diols) by reaction with epichlorohydrin. This polyol was subsequentiy allowed to react with a commercial triisocyanate, resulting in a tough, cross-linked polyurethane (129,135,139). ASTM and military specification tests on these polyurethanes for weather resistance, corrosion prevention, bUster resistance, and ease of cleaning showed them to compare quite favorably with standard resin formulations. 

Polyoxymethylene Ionomers. Ionic copolymers have been prepared from trioxane and epichlorohydrin, followed by reaction with disodium thioglycolate (76). The ionic forces in these materials dismpt crystalline order and increase melt viscosity (see Acetalresins). 

SAMs of OH-terrninated alkanethiols have been used in many surface modification reactions (Fig. 14). These reacted with OTS to yield a weU-ordered bdayer (322), with octadecyldimethylchlorosilane (323,324), with POCI3 (325—327), with trifluoroacetic anhydride (328), epichlorohydrin (329), with alkyhsothiocyanate (330), with glutaric anhydride (331), and with chlorosulfonic acid (327). 

A polymethacrylate copolymer is modified by successive reaction with epichlorohydrin, w-aminophenylboric acid, and nitric acid to introduce a 1-amino-(2 -nitrophenyl-5 -boric acid)-2-hydroxyl-3-o-propyl group. The modified polymethacrylates are used as chromatographic support materials and can be used to analyze biological materials without prior deproteinization (35). 

Substitution of an additional nitrogen atom onto the three-carbon side chain also serves to suppress tranquilizing activity at the expense of antispasmodic activity. Reaction of phenothia zine with epichlorohydrin by means of sodium hydride gives the epoxide 121. It should be noted that, even if initial attack in this reaction is on the epoxide, the alkoxide ion that would result from this nucleophilic addition can readily displace the adjacent chlorine to give the observed product. Opening of the oxirane with dimethylamine proceeds at the terminal position to afford the amino alcohol, 122. The amino alcohol is then converted to the halide (123). A displacement reaction with dimethylamine gives aminopromazine (124). ... 

One such agent is synthesized from 2-methyl imidazole by reaction with epichlorohydrin under acidic conditions. This produces the antiprotozoal agent ornidazole (26). ... 

Virtually all epoxy resins are made with starting materials based on epichlorohydrin, principally by reaction with bisphenol A. It is also used for the preparation of resins to increase the wet strength of paper. Both epichlorohydrin and glycidol are used in the manufacture of pharmaceuticals. 

Kim et al. (19) also observed that the ee of recovered epichlorohydrin was reduced to 17% in the second hydrolysis reaction with Jacobsen s Co-OAc salen catalyst, if the catalyst was not regenerated with acetic acid in air. Although they attributed the loss of enantioselectivity to the reduction of Co(lll) to Co(ll) salen complex after the HKR reaction, no spectroscopic evidence was provided. Therefore, we probed the catalyst by UV-Vis and XANES spectroscopy before and after the HKR reaction. 

Effect of dimer formation on deactivation. Another possible mode of deactivation is formation of inactive Co dimers or oligomers. To test for these species, we examined the ESI-mass spectram of fresh and deactivated Co-salen catalysts in dichloromethane solvent (22). The major peak in the mass spectram occurred at m/z of 603.5 for both Jacobsen s Co(II) and Co(III)-OAc salen catalysts, whereas much smaller peaks were observed in the m/z range of 1207 to 1251. The major feature at 603.5 corresponds to the parent peak of Jacobsen s Co(II) salen catalyst (formula weight = 603.76) and the minor peaks (1207 to 1251) are attributed to dimers in the solution or formed in the ESI-MS. The ESI-MS spectrum of the deactivated Co-salen catalyst, which was recovered after 12 h HKR reaction with epichlorohydrin, was similar to that of Co(II) and Co(III)-OAc salen. Evidently, only a small amount of dimer species was formed during the HKR reaction. However, the mass spectram of a fresh Co(III)-OAc salen catalyst diluted in dichloromethane for 24 h showed substantial formation of dimer. The activity and selectivity of HKR of epichlorohydrin with the dimerized catalyst recovered after 24 h exposure to dichloromethane were similar to those observed with a fresh Co-OAc salen catalyst. Therefore, we concluded that catalyst dimerization cannot account for the observed deactivation. 

Condensation of that intermediate with epichlorohydrin in the presence of a catalytic amount of piperidine affords the chlorohydrin 213, admixed with some epoxide. Reaction with tertiary butylamine completes construction of the propanolamine side chain. Displacement of the remaining halogen atom of 214 with morpholine under more strenuous conditions affords timolol (215). ... 

Polyepichlorohydrin and dimethylamine Polymerisation of epichlorohydrin in carbon tetrachloride with boron trifluoride/ether catalyst, then reaction with dimethylamine. Applied to cotton by exhaust method or pad-dry. Scheme 10.65 Good yields with direct dyes using only 2 g/l salt. Excellent build-up with most reactive dyes only 10% of normal salt usage needed for low-reactivity dyes and none for highly reactive types. Washing fastness very good but light fastness impaired. 

Figure 25.9 Epichlorohydrin can be used to activate the hydroxyl group of mPEG, creating an epoxy derivative. Reaction with amine-containing molecules yields secondary amine bonds.

Apart from the alkenyl succinic anhydrides, other cyclic anhydrides are solids, requiring the use of a delivery solvent, or a solid-state reaction. Apart from succinic anhydride, phthalic (PA) (Figure 4.2a) (Risi and Arseneau, 1958) and maleic anhydride (MA) have also been extensively studied (Figure 4.2b) (Clemons etal., 1992). Goethals and Stevens (1994) have reported reaction of wood with glutaric (Figure 4.2c) or cyclohexane-1,2-dicarboxylic anhydride (Figure 4.2d) and subsequent reaction with epichlorohydrin. 

Reaction with the excess epichlorohydrin causing the low molecular weight polymer to have terminal epoxy groups... 

The reaction actually involves the sodium salt of bisphenol A since polymerization is carried out in the presence of an equivalent of sodium hydroxide. Reaction temperatures are in the range 50-95°C. Side reactions (hydrolysis of epichlorohydrin, reaction of epichlorohydrin with hydroxyl groups of polymer or impurities) as well as the stoichiometric ratio need to be controlled to produce a prepolymer with two epoxide end groups. Either liquid or solid prepolymers are produced by control of molecular weight typical values of n are less than 1 for liquid prepolymers and in the range 2-30 for solid prepolymers. 

Epichlorohydrin is reacted with a variety of hydroxy, carboxy, and amino compounds to form monomers with two or more epoxide groups, and these monomers are then used in the reaction with bisphenol A [Lohse, 1987]. Examples are the diglycidyl derivative of cyclohex-ane-l,2-dicarboxylic acid, the triglycidyl derivatives of p-aminophenol and cyanuric acid, and the polyglycidyl derivative of phenolic prepolymers. Epoxidized diolefins are also employed (Sec. 9-8). 

Schlack [2] and Castan [3,4] are credited with the earliest U.S. patents describing epoxy resin technology. Greenlee [5] further emphasized the use of bisphenols and their reaction with epichlorohydrin to yield diepoxides capable of reaction with crude tall oil resin acids to yield resins useful for coatings. The use of diepoxide resins that are cured with amines was reported by Whittier and Lawn [6] in a U.S. patent in 1956. 

Reactions of this type have been widely used for the synthesis of 1,5-benzoxazepines by the reactions of o-aminophenols and their derivatives with a variety of functionalized three-carbon chains. Thus reaction with 3-bromo-l-chloropropane gives (360) and reaction with 3-chloropropionyl chloride gives the analogous 4-oxo derivative. Similarly a,/3-unsatur-ated Icetones give (361), /3-ketoesters give (362), l,3-oxazolid-5-ones give (363), and the reaction of the sodium salt of N-methanesulfonyl-o-aminophenol with epichlorohydrin gives... 

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