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United States Patent Office Patented Mar 3,239,568 United States Patent Office Patented Mar. 8, 1966 2 the metal atom bonded to the oxygen atom of the alkoxide 3,239,568 molecule. MANUFACTURE OF ALKALMETAL (COAEPOUNDS Thus the alkali metallometallic alkoxides of this inven David O. De Pree and anaes D. Johnston, Baton Rotage, tion are bifunctional compounds-that is they contain two La., assignors to Ethyl Corporation, New York, N.Y., 5 reactive centers. One of the striking features of this in a corporation of Virginia vention is that in a reaction with a hydrocarbon halide or No Drawing. Filled Aug. 9, 1960, Ser. No. 48,356 hydrocarbon sulfate alkylating agent only the “metal 6 Claims. (C. 260-632) lo,' i.e. This invention involves a process for the manufacture O of organic compounds, in particular, alkali metal alkox --M ides, which can easily be converted to the corresponding functional group reacts, and the "metallic,” i.e. alcohols. This invention is also concerned with bimetal lic organometallic compounds which are utilized in pre paring the alkali metal alkoxides of this invention. --OM Prior to this invention no satisfactory method was reactive center does not. known for increasing the molecular weight of metal alk Although the terms alkali metallometallic alkoxide and oxides using direct reactions of organic halides or organic metal alkoxide are employed throughout this specifica Sulfates. A process which employs hydrocarbon halides tion the process of this invention can be carried out using or hydrocarbon sulfates, and in particular, long chain hy 20 the corresponding alkenoxides and aryioxides, as these drocarbon halides, to produce alkali metal alkoxides of compounds are essentially equivalent to alkoxides for the increased chain length would be of particular value to purposes of this invention. the industry in providing a method for ultimately produc In carrying out the processes of this invention, it is ing the useful higher chain length alcohol itself. Such a preferred that the alkali metal alkoxide and alkali metal process has now been discovered. It is simple and eco 25 lometallic alkoxide contain sodium as the alkali metal nomical, and in its preferred form it utilizes readily constituent because of its ready availability, cheapness available, low cost hydrocarbon halide starting materials. and high reactivity. Furthermore, in order to produce Accordingly, it is an object of this invention to provide the most desirable alkali metal alkoxides from cheap raw a new and novel process for the direct preparation of materials having good reactivity it is preferred that the alkali metal alkoxides of increased molecular weight. 30 hydrocarbon portion of the alkylating agent contain from A particular object is to provide a process for the direct about 6 to about 20 carbon atoms and that the alkali preparation of alkali metal alkoxides of increased molec metallometallic alkoxide reactant contain from 1 to about ular weight from a reaction between an alkali metalio 4 carbon atoms. Thus the alkali metal alkoxides pro metallic alkoxide and a hydrocarbon halide. A still fur duced from these reactants by the process of this inven ther object is to porvide a process for the preparation of 35 tion contain about 7 through about 24 carbon atoms. A alcohols of increased molecular weight. Also an object more specific embodiment of this invention, and more of this invention, is to provide a process for the perpara fully demonstrative thereof, is the reaction of sodio-sodi tion of the alkali metaliometallic alkoxide utilized in the um methoxide with octyl bromide to produce sodium reaction with a hydrocarboa halide to prepare alkali metal nonoxide, which can be converted by hydrolysis to nonyl lic alkoxides of increased molecular weight. Other ob 40 alcohol. jects of this invention will be apparent from the follow In carrying out the reaction between an alkali metallo ing discussion. metailic alkoxide and said alkylating agents, the propor These and other objects of this invention are accom tions of the reactants employed, and the temperature of plished by providing a process for the preparation of the reaction are important and should preferably be main alkali metal alkoxides of increased molecular weight which tained within certain limits in order to achieve the de comprises reacting an alkali metallometallic alkoxide with sired alkali metal alkoixdes of increased molecular weight an alkylating agent, viz. hydrocarbon halide or a hydro in high yields and purity. In general between about 1. carbon Sulfate. and .5 equivalents of the alkoxide are employed per Also within the scope of this invention is a process for equivalent of hydrocarbon halide or hydrocarbon sulfate. the preparation of the above alkali metallometallic alk 50 The equivalent number of said halide is equal to the oxide which comprises reacting an alkali metal alkoxide number of carbon-halogen bonds contained therein; that Wtih a metalating agent at a temperature below the de of Said sulfate is equal to the number of carbon-sulfur composition temperature of the alkoxides formed and bonds contained therein, and said alkoxide has an equiv used as the reactant. In this embodiment alkali metals, alent number equal to the number of carbon-metal bonds alkali metal hydrides, or alkali metal amides are used as 55 therein. In order to avoid excessive by-product forma the metalating agent. tion and to achieve high yields, it is preferred to employ The term alkali metallometallic alkoxide, as used here essentially stoichiometric (i.e. equal equivalent) propor in, defines a bifunctional organometallic compound. One tions of the reactants based on one equivalent of hydro of the functional groups of this bifunctional compound is carbon halide or hydrocarbon sulfate for each equiavalent an alkali metal bonded directly to a carbon atom of the 60 of the alkali metallometallic alkoxide. The reaction tem alkoxide, i.e. perature employed is at least about -30° C. up to about the decomposition temperature of the reactants. How ever, it is generally preferred to employ a reaction tem --M perature of at least about 50° C. but below the decomposi and the other functional group is a metal bonded direct 65 tion temperature of the alkali metallometallic alkoxide in ly to the oxygen atom of said alkoxide, i.e. order to achieve a faster reaction rate and higher yields. Thus the process of this invention provides a direct route to alkali metal alkoxides of increased molecular weight --o-r from hydrocarbon halides. The product thereby pro In the term alkali metallometallic alkoxide the constituent 70 duced can be easily converted to the alcohol, or other designated as "metallo' is the alkali metal bonded direct valuable products. ly to a carbon atom and that designated as “metallic' is The alkali metallometallic alkoxides of this invention 3,239,568 3 4 are produced by a novel process which comprises reacting Example II an alkali metal alkoxide with a metalating agent selected from the group consisting of alkali metals, alkali metal To the reaction vessel described in Example I is added hydrides and alkali metal amides at a temperature below 1 mole of sodio-sodium methoxide as a 20 percent sus the decomposition temperature of said alkoxides. The 5 pension in n-octane. To this mixture is added slowly alkali metal alkoxide which is preferably employed in over a period of about 2 hours n-octylbromide, the tem this process is one which contains at least one hydrogen perature of the reaction mixture being maintained at atom on the alpha-carbon atom. Illustrative of such about 25° C. After the addition is completed the tem alkoxides are sodium methoxide, sodium ethoxide, Sodium perature of the reaction mixture is raised to about 100' butoxide and the like. Alkali metallometallic alkoxides C. and held there for about /2 hour to complete the re produced from such metal alkoxides have greater stability 10 action. The reaction mixture is cooled and the solids and thus give greater processing flexibility in the reaction (the sodium salt of n-nonyl alcohol and sodium bromide) with the hydrocarbon halide or hydrocarbon sulfate. are filtered off and hydrolyzed as in Example I. The The preferred metalating agents for use in preparing the water insoluble alcohol product (n-nonyl alcohol) is Sep alkali metallometallic alkoxides are sodium, sodium amide arated as a liquid. This material is then fractionated at and sodium hydride because of their cheapness, avail atmospheric pressure and a fraction boiling at about 230 ability or ease of preparation. Therefore, within the C. is collected and identified as n-nonyl alcohol, a water scope of this invention and a preferred embodiment insoluble, colorless liquid melting at -5° C. thereof is a process for the preparation of a-sodio-sodium Example III alkoxides which comprises reacting a sodium alkoxide, 20 containing at least one hydrogen atom on the C-carbon To a reaction vessel as described in Example I is added atom, with a metalating agent selected from the group 2 moles of o-sodio-sodium 2-butenoxide as a 20 percent consisting of sodium, sodium amide and sodium hydride suspension in mineral oil. The temperature of this mix- . at a temperature below the decomposition temperature of ture is raised to about 50° C. and thereafter the one mole Said alkoxides. of diethyl sulfate is added slowly over a period of about In general the reaction to produce alkali metallometal 1 hour after which addition the temperature of the re lic alkoxides is carried out in the absence of a Solvent, at action mixture is then raised to 150° C. for a period of a temperature ranging from about 50 to the decomposi about 72 hour in order to complete the reaction. Then tion temperature of the product produced and in the the reaction mixture is cooled, filtered under nitrogen and presence of good mixing or grinding, such as is obtained 30 the solids (the sodium salt of 4-hydroxy-2-hexene and in a balmill reactor.
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