Standard Epichlorohydrin

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. 

In addition, glycidyl esters are produced by the reaction of cycloahphatic carboxyUc acids with epichlorohydrin, followed by dehydrohalogenation with caustic. Such products are characterized by low viscosities (ca 500 mPa-s (=cP)). Reactivity of the glycidyl esters more closely resembles the standard bisphenol—epichlorohydrin resins. 

Compounds are prepared by a fairly standard sequence which consists of condensation of an appropriate phenol with epichlorohydrin in the presence of base. Attack of phenoxide can proceed by means of displacement of chlorine to give epoxide (45) directly. Alternatively, opening of the epoxide leads to anion 44 this last, then, displaces halogen on the adjacent carbon to lead to the same epoxide. Reaction of the epoxide with the appropriate amine then completes the synthesis. 

Alkylation of the monobenzyl ether of hydroquinone 34 with mesylate 35, gives ether 36. Hydrogenolytic removal of the benzyl group gives phenol 37. This affords cicloprolol (38) when subjected to the standard alkylation scheme 17]. In much the same vein, alkylation of g-hydroxy-phenylethanol 39, obtainable from the corresponding phenylacetic acid, with epichlorohydrin... 

Hydrolytic Kinetic Resolution (HKR) of epichlorohydrin. The HKR reaction was performed by the standard procedure as reported by us earlier (17, 22). After the completion of the HKR reaction, all of the reaction products were removed by evacuation (epoxide was removed at room temperature ( 300 K) and diol was removed at a temperature of 323-329 K). The recovered catalyst was then recycled up to three times in the HKR reaction. For flow experiments, a mixture of racemic epichlorohydrin (600 mmol), water (0.7 eq., 7.56 ml) and chlorobenzene (7.2 ml) in isopropyl alcohol (600 mmol) as the co-solvent was pumped across a 12 cm long stainless steel fixed bed reactor containing SBA-15 Co-OAc salen catalyst (B) bed ( 297 mg) via syringe pump at a flow rate of 35 p,l/min. Approximately 10 cm of the reactor inlet was filled with glass beads and a 2 pm stainless steel frit was installed at the outlet of the reactor. Reaction products were analyzed by gas chromatography using ChiralDex GTA capillary column and an FID detector. 

Biological. Bridie et al. (1979) reported BOD and COD values of 0.03 and 1.16 g/g using filtered effluent from a biological sanitary waste treatment plant. These values were determined using a standard dilution method at 20 °C for a period of 5 d. When a sewage seed was used in a separate screening test, a BOD value of 0.16 g/g was obtained. The ThOD for epichlorohydrin is... 

NIOSH Criteria for a Recommended Standard. .. Occupational Exposure to Epichlorohydrin. DHEW (NIOSH) Pub No 76-206, p 152. National Institute for Occupational Safety and Health, US Department of Health, Education and Welfare. Washington, DC, US Government Printing Office, 1976... 

The American Conference of Governmental Industrial Hygienists (ACGIH) (1997) has recommended 1.9 mg/m as the 8-h time-weighted average threshold limit value for occupational exposures to epichlorohydrin in workplace air. Similar values have been used as standards or guidelines in many countries (International Labour Office, 1991). 

Seven cancers were observed (7.3 expected) among 230 workers in the plastics and additives production area where there was potential for exposure to epichlorohydrin. An excess of lung cancer was observed among the 44 workers who had been employed in the production of epichlorohydrin, which had been manufactured at the plant between 1961 and 1965 (levels of exposure not reported) (standardized mortality ratio (SMR), [4.4] 4 observed versus 0.91 expected p = 0.03). 

The product obtained in a standard diglycidyl ether reaction with epichlorohydrin and alkali was an off-white crystalline powder melting at 191 -193 0. 

Figs. 13 and 14 plot the experimental (points) and simulated (solid lines) concentration profile versus time for (S)-epichlorohydrin, (R)-epichlorohydrin, and water under the standard HKR operating conditions using 0.5 and 0.28 mol-% catalyst (relative to racemate), respectively. Also shown is the simulated and observed evolution of epichlorohydrin ee and conversion over the course of the reaction. Fig. 15 gives the corresponding profiles for glycidol and DCP at both catalyst concentrations. 

Fig. 16 Hydrolysis of (S)-epichlorohydrin under standard conditions (see Tab. 6 for conditions). Experimental X (S)-epichlorohydrin, O water. Numerical simulation solid lines.

Bogdal et al. have obtained unsaturated polyesters in polyaddition reactions of alkylene oxides such as epichlorohydrin and acid anhydrides (maleic and phthalic anhydrides) in the presence of lithium chloride as catalyst under microwave irradiation conditions (Scheme 14.22) [51, 52]. In the standard procedure, a mixture of 0.10 mol phthalic anhydride and 0.10 mol maleic anhydride with 0.010 mol ethylene glycol, 0.20 mol epichlorohydrin, lithium chloride (0.1% w/w) was placed in a... 

Triglycidylp-AminophenoI DerivedResins. Resins derived from triglycidyl -aminophenol [5026-74-7] originally developed by Union Carbide Corp. (7) are currendy marketed by CIBA-GEIGY. Synthesis is conducted by reaction of epichlorohydrin with the phenoHc and amino groups followed by dehydrohalogenation. The product is a viscous Hquid (1.5-5 Pa-s (15—50 P) at 25 C) which is considerably more reactive toward amines than standard bisphenol A-derived resins. The epoxy equivalent weight is 105—114. 

The above criteria were employed to select several commercially supplied Class PS elastomers for laboratory screening by employing selected tests taken from National Bureau of Standards NBSIR 77-1437(j4) and ANSI/ASTM D-3667-78 specifications for "Rubber Seals Used in Flat-Plate Solar Collectors". Four silicone, three EPDM, two fluorocarbon, three epichlorohydrin, one ethylene-acrylic, one polyacrylic, one chlorosulfonated polyethylene, one bromobutyl and two butyl rubbers were studied in these screening tests. These materials are identified in Table I and those compositions which were revealed by their manufacturers are shown in Table II. Undoubtedly some materials which should have been included were omitted however, we hope that this sampling will provide an indication of the applicability of a wide range of materials for use as sealants in thermal solar collectors. 

Abstract The modified equation-of-motion coupled cluster approach of Sekino and Bartlett is extended to computations of the mixed electric-dipole/magnetic-dipole polarizability tensor associated with optical rotation in chiral systems. The approach - referred to here as a linearized equation-of-motion coupled cluster (EOM-CCl) method - is a compromise between the standard EOM method and its linear response counterpart, which avoids the evaluation of computationally expensive terms that are quadratic in the field-perturbed wave functions, but still yields properties that are size-extensive/intensive. Benchmark computations on five representative chiral molecules, including (P)-hydrogen peroxide, (5)-methyloxirane, (5 )-2-chloropropioniuile, (/ )-epichlorohydrin, and (75,45)-norbornenone, demonstrate typically small deviations between the EOM-CCl results and those from coupled cluster linear response theory, and no variation in the signs of the predicted rotations. In addition, the EOM-CCl approach is found to reduce the overall computing time for multi-wavelength-specific rotation computations by up to 34%. 

Bisphenol A and F n. Dihydroxydiphenyldi-methylmethane, mol wt 224.1. Insoluble in water. Used in the manufacture of phenolic and epoxy resins. Condensation product formed by reaction of two (bis) molecules of phenol with acetone. This polyhydric phenol is a standard resin intermediate, along with epichlorohydrin, in the production of epoxy resins (See image). 

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