1- Chloro-2-propanol preparation

HVP products prepared by hydrolysis with HCl contain varying amounts of glycerol chlorohydrins, such as 3-chloro-l,2-propanediol [96-24-2] and l,3-dichloro-2-propanol [96-23-1J, depending on reaction conditions and Hpid contents of the starting material (135). As a result of their toxicides, regulating agencies in many countnes have restncted the contents of these compounds in food. 

Diphenoxy-2-propanol (3) was prepared from phenol and epichlorohydrin (l-chloro-2,3-epoxypropane), as previously described,8 and recrystallized three times from 2-propanol to yield white crystals, m.p. 82-82.5°C. The nmr spectrum in CDC1- (Varian EM-390 spectrometer) exhibited resonances (in ppm (6) relative to tetramethylsilane) at 3.0 (1H, doublet,... 

If a diastereomeric mixture of (S,S)-2,5-dimethyl-3.4-hexanediol esters 2 and 3 reacts with methylmagnesium bromide, the result is kinetic resolution, as verified for R1 = Bn. The diastereomeric mixture was prepared from the racemic ethylene glycol a-chloro boronic ester via transesterification with chiral diol. The products isolated were (S,S)-2,5-dimethyl-3,4-hexanediol [(/ )-2-phcnyl-l-methylethyl]boronate, diastereomeric ratio >95 5 as indicated by the rotation of the (/ )- -phenyl-2-propanol derived by deboronation with hydrogen peroxide, and (S,S)-2,5-dimethyl-3.4-hexanediol methylboronate. Phenylacetaldehyde was identified by 1H NMR4. 

The preparation of l-azido-2-propanol (0.49 mole) from l-chloro-2-propanol and sodium azide (0.51 mole) in 33% aqueous methanol (by volume) has been reported to give a 55 % yield [9a]. 

Prepared from l-azido-3-chloro-2-propanol and aqueous sodium hydroxide as described for glycidyl nitrate. See W. L. Petty and P. L. Nichols, Jr., J. Amer. Chem. Soc. 76, 4385 (1954). 

Two further preparations of 3-nitropropanal 1 have been claimed in the literature by treatment of 1-chloro-3-nitro-2-propanol with potassium hydroxide,5 and by reaction of the 4-isopropyl-2-oxazolin-5-one anion with nitroethene.6 These alternate methods are less suited and less economic for the preparation of 3-nitropropanal 1 on a multigram scale. 

Stephenson has developed a convenient procedure for preparing J-chloro-3-phenoxy-2-propanols from epichlorohydrin nnd phenols, which is economical of reagents and minimizes the formation of undesirable side-products (Eq. 600). He has also greatly extended the applicability of hydrogen chloride transfer for the preparation of epoxides. ... 

Procedures for isolation and measurement of lipids in foods include exhaustive Soxhlet extraction with hexane or petroleum ether (AOAC, 1995 see Basic Protocol 1), chloro-form/methanol (Hanson and Olley, 1963 Ambrose, 1969), chloroform/methanol/water (Folch et al., 1957 Bligh and Dyer, 1959 see Basic Protocol 2 and Alternate Protocol 2), acid digestion followed by extraction (see Basic Protocol 4), or, for starchy material, extraction with n-propanol-water (e.g., Vasanthan and Hoover, 1992 see Basic Protocol 3). Each method has its own advantages and disadvantages and successful measurement of lipid content is often dictated by the type of sample and extraction medium employed. Commercial extraction and preparation of edible oils are explained in the literature (Williams, 1997). 

Hydroxyglutaronitrile has been prepared by the action of potassium cyanide on 1,3-dichloro-2-propanol 3 s or on 4-chloro-... 

By reacting 2-aminopyridine and epichlorohydrin, Knunjanz187 obtained the hydrochloride of 3-hydroxy-3,4-dihydro-2H-pyrido[l,2-a]pyrimidine (131 R = OH). Analogous products from 4-methyl-, 5-methyl-, 5-halo- and 3,5-dibromo-substituted 2-aminopyridines have been prepared by Soviet workers.188,189 The same products arose from the reaction of 2-aminopyridines and l,3-dichloro-2-propanol.188 189 Klusis and Kuthevicius190 reacted 2-aminopyridine with 3-chloro-1,2-propanediol (127) or 2,3-... 

Calculation Prepare a standard curve for the summed signal areas for each of the controls against the calculated propylene chlorohydrin concentrations, in mg/kg, derived from the actual weight of chlorohydrin isomers used. Using the summed signal areas corresponding to the l-chloro-2-propanol and 2-chloro-1 -propanol from the sample, determine the concentration of mixed propylene chlorohydrins, in mg/kg, in the sample by reference to the calibration plot. 

RC = CCH,X — RCX = C==CH,. /S.y- and 7,S-Acetylenic alcohols can be transformed to the halides in better yields by an alternative procedure, which consists in their esterification with p-toluenesulfonyl chloride and subsequent cleavage of the ester by the action of sodium iodide, lithium chloride, or calcium bromide in an appropriate solvent (60-90%). Halo ethers are prepared by the action of phosphorus tribromide on hydroxy ethers, as in the preparation of /3-ethoxyethyl bromide (66%). In a similar manner, /3-halo esters have been prepared without appreciable dehydration of the /3-hydroxy ester (40-60%). The reaction of cyanohydrins leads to a-halo nitriles. Treatment of 2-nitro-l-propanol with phosphorus pentachloride gives l-chloro-2-nitropropane (47%). ... 

Halomercaptans are converted to thietanes by treatment with a as exemplified by the formation of 3-hydroxythietane 21 from 3-chloro-l-mercapto-2-propanol 20 4-thiocyano-2-pentanol 22 is converted to a mixture of cis- and trans-2,4-dimethylthietane 23 by treatment with sodium hydride. The latter reaction involves displacement of cyanate ion by the mercaptide ion. 2,2,4-Trimethylthietane was also prepared by this method. 

In order to prepare PLA nanocomposites with highly dispersed cellulose nanocrystals and porous PLA-based scaffolds with enhanced mechanical properties and thermal stability, CNCs have been incorporated into PLA fibres by electrospinning method. Fibrous biocomposite mats consisting of PLA and CNCs have been electrospun from solvent or solvent mixtures such as l,l,l,3,3,3-hexafluoro-2-propanol (HFP), DMF/chloro-form and DMF/tetrahydrofuran (THF). The electrospun PLA/CNCs bionanocomposites have demonstrated rapid in vitro biodegradability and cytocompatible properties, and could be potentially suitable in tissue engineering. ... 

One method for the preparation of epoxides from alkenes involves (1) treating the alkene with chlorine or bromine in water to form a chlorohydrin (or bromohydrin) followed by (2) treating the halohydrin with a base to bring about intramolecular displacement of Cl . These steps convert propene first to l-chloro-2-propanol and then to methyloxirane (propylene oxide). 

Preparation by oxidation of l-(3-chloro-2-methoxyphenyl)-l-propanol with chromium ttioxide in the presence of dilute sulfuric acid in acetone [6477],... 

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