Europaisches Patentamt 19 European Patent Office Office europeen des brevets © Publication number : 0 579 362 A1 EUROPEAN PATENT APPLICATION © Application number : 93303893.7 © int. ci.5: C07C 31/36, C07C 29/32 @ Date of filing : 19.05.93 © Priority: 13.07.92 JP 184910/92 @ Inventor: Watanabe, Hiroyoshi 18.12.92 JP 338584/92 3-4-1-141, Toriishi Takaishi-shi, Osaka-fu (JP) Inventor : Hayakawa, Fumie @) Date of publication of application : 4-7-3-342, Kamo 19.01.94 Bulletin 94/03 Takaishi-shi, Osaka-fu (JP) © Designated Contracting States : © Representative : Stuart, Ian Alexander et al DE FR GB IT NL MEWBURN ELLIS 2 Cursitor Street London EC4A 1BQ (GB) © Applicant : MITSUI TOATSU CHEMICALS, Inc. 2-5 Kasumigaseki 3-chome Chiyoda-Ku Tokyo 100 (JP) © Method for preparing 2,3-dichloro-1-propanol and 3-chloro-1-propanol. © A method for preparing 2,3-dichloro-l- propanol and 23-chloro-l-propanol is here dis- closed which comprises the step of reacting 1,2-dichloroethane with methanol by irradiation with light in the presence of at least one com- pound selected from europium compounds, samarium compounds and ytterbium com- pounds, and if necessary, in the additional pre- sence of a zeolite. CM CO CO o> ro- ta LU Jouve, 18, rue Saint-Denis, 75001 PARIS 1 EP 0 579 362 A1 2 The present invention relates to a method for pre- As a method to solve these problems, the pres- paring 2,3-dichloro-1-propanol and 3-chloro-1- ent inventor have suggested a method for preparing propanol. 2,3-dichloro-1-propanol and 3-chloro-1-propanol by More specifically, the present invention relates to irradiating methanol and 1 ,2-dichloroethane as start- a method for preparing 2,3-dichloro-1-propanol and 5 ing materials with light in the presence of a peroxide 3-chloro-1-propanol by hydoxymethylating 1,2-di- and/or an azo compound (Japanese Patent Applica- chloroethane with methanol. These products are in- tion No. 325516/ 1990), and a method for preparing dustrially important in themselves or as intermediates 2,3-dichloro-1-propano and 3-chloro-1-propanol by of reactions. irradiating methanol and 1 ,2-dichloroethane as start- Since 2,3-dichloro-1-propanol can easily be con- 10 ing materials with light in the presence of a carbonyl verted into epichlorohydrin with a caustic alkali or milk compound (Japanese Patent Application No. of lime, it is useful as a precursor of epichlorohydrin 250700/1991). which is a raw material of an epoxy resin and a syn- These methods in which the reaction is caused to thetic rubber. On the other hand, 3-chloro-1-propanol occur by the light irradiation can remarkably simplify is also a useful substance and industrially important 15 the manufacturing process, as compared with a con- as an intermediate for a reaction. ventional method, but they have the following prob- Nowadays, 2,3-dichloro-1-propanol which is the lems to be solved. That is to say, according to knowl- precursor of epichlorohydrin can be industrially man- edge of the present inventors, in the method in which ufactured by a method which comprises chlorinating the light irradiation is done in the presence of the per- propylene at a high temperature to form allyl chloride, 20 oxide, the peroxide in an amount equimolar with me- and then treating allyl chloride with chlorine and water thanol is required to produce a hydromethyl radical to form a chlorohydrin, or a method which comprises from methanol, and besides danger attends the han- acetoxylating propylene with acetic acid in the pres- dling of the peroxide. On the other hand, in the meth- ence of a palladium catalyst to form allyl acetate, hy- od in which the light irradiation is done in the pres- drolyzing allyl acetate to form allyl alcohol, and then 25 ence of the azo compound and the method in which chlorinating it. In addition, Japanese Patent Applica- the light irradiation is done in the presence of the car- tion Laid-open No. 297333/1988 has suggested a bonyl compound, an improvement effect of activation method which comprises chlorinating acetone in the is much lower than in the case of using the peroxide. presence of an iodine chloride catalyst and a lithium The present inventors have intensively investi- chloride catalyst to form 1,3-dichloroacetone, and 30 gated to ameliorate such problems, and as a result, then reacting 1,3-dichloroacetone with isopropanol in they have found that when 1,2-dichloroethane is re- the presence of an aluminum isopropoxide catalyst. acted with methanol by the irradiation of light in the On the other hand, as methods for preparing 3- presence of at least one compound selected from eu- chloro-1-propanol, there are known a method in ropium compounds, samarium compounds and ytter- which a chloropropanol mixture obtained by treating 35 bium compounds, 1,2-dichloroethane is hydroxyme- 1 ,3-propanediol with hydrogen chloride is subjected thylated with methanol to produce 2,3-dichloro-1- to fractional distillation several times [Organic Syn- propanol and 3-chloro-1-propanol. In consequence, thesis Coll. Vol. 1 , 533-534 (1 964)], a method in which the present invention has now been completed. acrolein is reacted with hydrogen chloride in an alco- In addition, the present inventors have also found hol to produce an acetal of 3-chloropropionaldehyde, 40 that when the above-mentioned reaction is carried and this acetal is then reduced in the presence of a out in the presence of a zeolite, a reaction rate and ruthenium catalyst (Belgian Patent No. 634845), a yields of 2,3-dichloro-1-propanol and 3-chloro-1- method in which hydrogen chloride is added to acro- propanol are remarkably increased. lein to form 3-chloropropionaldehyde, and this is then That is to say, the present invention is directed to reduced with an alkali metal bonarate (Japanese Pa- 45 a method for preparing 2,3-dichloro-1-propanol and tent Publication No. 42769/1977), and a method in 3-chloro-1-propanol which comprises the step of re- which epichlorohydrin is reduced with zinc borohydr- acting 1,2-dichloroethane with methanol by the irra- ide supported on silica gel to obtain a mixture of 3- diation of light in the presence of at least one com- chloro-1-propanol and propylene chlorohydrin [yield pound selected from europium compounds, samari- of 3-chloro-1-propanol = 60%, J. C. S. Chem. Comm., 50 urn compounds and ytterbium compounds. p. 1334(1990)]. Furthermore, the present invention is also direct- However, in each of these methods, there are ed to a method for preparing 2,3-dichloro-1-propanol some problems such as the use of the prolonged and 3-chloro-1-propanol which comprises the step of manufacturing process because of requiring reac- reacting 1,2-dichloroethane with methanol by the ir- tions in the several steps, the use of the expensive 55 radiation of light in the presence of a zeolite and at catalysts and the consumption of a large amount of least one compound selected from europium com- chlorine for the chlorination of the raw material. Thus, pounds, samarium compounds and ytterbium com- a simple and economical method is desired. pounds. 2 3 EP 0 579 362 A1 4 DETAILED DESCRIPTION OF THE INVENTION An amount of the zeolite to be used may be in the range of from 0.01 to 100 parts by weight, preferably Examples of the europium compounds, samari- from 0.05 to 50 parts by weight based on 1000 parts um compounds and ytterbium compounds which can by weight of a mixture solution comprising at least one be used in a method of the present invention include 5 compound selected from the group consisting of eu- powders of these metals; trivalent oxides, trivalent hy- ropium compounds, samarium compounds and ytter- droxides, trivalent fluorides, divalent and trivalent bium compounds, 1,2-dichloroethane and methanol. chlorides, trivalent bromides and trivalent iodides of As the light for the light irradiation in the present these metals; salts of mineral acids such as trivalent invention, there can be used white light having a wide nitrates, trivalent sulfates and trivalent phosphates of 10 wave range of from ultraviolet light to visible light or these metals; salts of organic acids such as trivalent monochromatic light, but the preferable light is the acetates, trivalent propionates and trivalent oxalates light generated from a mercury vapor lamp or a flash- of these metals; alkoxides such as trivalent methox- lamp, or laser beams. With regard to the manner of ides, trivalent ethoxides, trivalent isopropoxides and the light irradiation, a light source may be disposed trivalent butoxides of these metals; chelate com- 15 outside or inside the reaction vessel, and a more ef- pounds such as tris(acetylacetonate) salts, fective manner may be selected. tris(heptafluorobutanoylpivaloylmethanate) salts and 1,2-dichloroethane which can be used as the tris(pivaloyltrifluoroacetonate) salts of these metals; starting material in the present invention can be inex- and trivalent carbonates, trivalent perchlorates and pensively manufactured usually as a raw material of trivalent tungstates of these metals. 20 vinyl chloride by the heat chlorination of ethylene or The europium compounds, samarium com- the oxy-chlorination of ethylene. With regard to the pounds and ytterbium compounds may be in the state purity of 1,2-dichloroethane usable in the present in- of anhydrides or hydrates. In particular, the salts of vention, a purity of 1,2-dichloroethane for use in the the mineral acids, the salts of the organic acids, the manufacture of usual vinyl chloride is enough.