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United States Patent Office Patented Jan 3,555,020 United States Patent Office Patented Jan. 12, 1971 2 3,555,020 hydride' process; (4) halogenation of a beryllium hy PROCESSES FOR MAKING COMPLEX COM. dride-tertiary amine complex, hereinafter called the POUNDS OF HALOBERYLLIUM HYDRIDE "halogenation process"; and (5) hydrohalogenation of WITH TERTARY AMENES a beryllium hydride-tertiary amine complex, hereinafter Lawrence H. Shepherd, Jr., Baton Rouge, La., assignor 5 called the "hydrohalogenation process.” Of the foregoing to Ethyl Corporation, New York, N.Y., a corpora processes, the amine-complex process is preferred be tion of Virginia cause of the ease of purification of the reactants and No Drawing. Original application July 3, 1967, Ser. No. products and because of the relative stability of the re 652,652, now Patent No. 3,483,219, dated Dec. 9, 1969. This application Sept. 22, 1969, Ser. No. actants; this simplifies the handling of the reactants and 860,064 O particularly the procedure for weighing them into the Int, C. C07d 87/30 reactor. U.S. C. 260-247 The foregoing processes will be discussed separately 5 Claims and in detail below. In general, any tertiary amine complexes of beryllium hydride may be employed as reactants in the foregoing ABSTRACT OF THE DISCLOSURE 5 processes. However, beryllium hydride complexes of Novel complex compounds of haloberyllium hydride amines containing more than one tertiary amine radical with tertiary amines, such as certain alkyl amines, N,N- tend to be polymeric in structure and are therefore less dimethylbenzylamine, N,N - dimethylcyclohexylamine, desirable for the purposes of the present invention. N-methyl or N-ethyl pyrrolidine, N-methyl piperidine 20 All the operations constituting the above processes and N-methyl morpholine, are prepared (1) by reacting are carried out under an atmosphere inert with respect to a tertiary amine hydrohalide with a tertiary emine-beryl reactants and products. Because of its cheapness and avail lium hydride complex, (2) from anhydrous beryllium ability, nitrogen in the inert atmosphere of choice but halide and a tertiary amine-beryllium hydride complex, helium, neon, argon, krypton, Xenon, gaseous saturated (3) from anhydrous beryllium halide, an alkali metal 25 aliphatic hydrocarbons or other inert gases may be em hydride and an excess of tertiary amine, (4) by halo ployed if desired. genation of a tertiary amine-beryllium hydride complex In the following examples, which illustrate the prep or (5) by hydrohalogenation of a tertiary amine-beryl aration of the compounds of this invention, all parts and lium hydride complex. The obtained complex com percentages are by weight unless otherwise specified. pounds are useful as intermediates for the production of pure beryllium hydride, a useful component for propel 30 Amine-complex process lants. The obtained complexes can be decomposed therm ally to pure metallic beryllium, or reacted with olefins or RN-HX--BeHNRHBeXNR-H-I-HR used as selective reducing agents. EXAMPLE 1. To a solution containing 7.2 grams of N-methyl pyr 35 rolidine beryllium hydride and 6.4 grams of free N-meth This application is a division of co-pending applica yl pyrrolidine in 200 milliliters of benzene, 7.1 grams of tion Ser. No. 652,652, filed July 3, 1967 now U.S. Pat trimethylamine hydrochloride was slowly added. Con ent 3,483,219. siderable gas was evolved and a homogenous solution This invention relates to and has as its principal ob 40 was produced. Benzene solvent was removed under ject the provision of a novel complex compounds of vacuum leaving 9.4 grams of a white crystalline solid. A haloberyllium hydrides with tertiary amines and the pro cryoscopic measurement in benzene showed the molecu vision of novel methods for the preparation of such lar weight of the solid to be 302. The melting point (un compounds. Other objects will appear hereinafter. corrected) in a sealed capillary was 194 to 198° C. The It has now been found that the foregoing objects are 45 product was anaylzed, with the following results. accomplished by the provision of haloberyllium hydride amine complexes of the general formula Theory for N methyl pyrrollidine HBeXA chioroberyllium Found hydride wherein X is a halogen and A a tertiary amine. More 50 H, millimoles per gram, weight specifically, X is a halogen of atomic number from 17 percent----------------------------- 7.27 (0.73) 7.70 (0.77) Be-------- 8.02(7.22) 7.70 (6.91) 53, inclusive, i.e., chlorine, bromine or iodine, and A Cl------ 7.12(25.3) 7.70(27.2) may be any of a large variety of tertiary amines of which Amine---------- 7. 57 (64.4) 7.70(65.1) the following are representative: trimethyl amine, di Molecular weight, 302 260 methylethyl amine, methyldiethyl amine, triethylamine, 55 dimethylalkyl amine wherein the alkyl group is a satur The molecular weight indicates that the compound ated straight-chain alkyl radical containing from 3 to 12 exists as a dimer in benzene solution. carbon atoms, inclusive, N,N-dimethylbenzyl amine, If the N-methyl pyrrolidine in the above example is N,N-dimethylcyclohexyl amine, N-methyl pyrrolidine, replaced by N,N-dimethylbenzyl amine; N,N-dimethyl N - ethyl pyrrolidine, N - methyl piperidine, N-methyl- 60 cyclohexyl amine; N-ethyl pyrrolidine; N-methyl piperi morpholine, tetramethylethylene diamine, triethylene di dine; or N-methyl morpholine similar results are obtained. amine, and tripropylene diamine. A variety of processes have been discovered for the EXAMPLE 2 preparation of the compounds of this invention. These The trimethylamine-chloroberyllium hydride complex processes are as follows: (1) reaction of a tertiary amine 65 was prepared in a manner similar to that of Example 1 hydrohalide with a beryllumu hydride-tertiary amine com by adding 9.5 grams of trimethylamine hydrochloride to plex, hereinafter referred to as the "amine-complex' 7.0 grams of the trimethylamine-beryllium hydride com process; (2) reaction of anhydrous beryllium halide with plex in 100 milliliters of benzene. Some unreacted solids a beryllium hydride-tertiary amine complex, hereinafter remained and were filtered off. Material insoluble in cold called the "halide-complex” process; (3) reaction of an- to benzene was recrystallized from hot benzene to give 6.0 hydrous beryllium halide with an alkali metay hydride grams of white crystals melting at 220 to 231 C. The and a tertiary amine, hereinafter called the "halide product was analyzed, with the following results. 3,555,020 4. Theory for filter and the residue washed on the filter with a small limethylamine amount of N-methyl morpholine. The combined filtrate chloroberyllium and washings are distilled under vacuum at 100 to 150 C. Found hydride A white crystalline residue of chloroberyllium hydride-N- H-, millimoles per gram, weight percent------------ 10. 2 (1.01) 9, 62(0.96) methyl morpholine complex is obtained. All operations are Be-- 10, 13(9.14) 9.62(8.60) carried out under an atmosphere of dry nitrogen. Cl-- 9.34 (34, i) 9.62(34.9) Amil 9.34 (55.6) 9.62 (56.5) When the N-methyl morpholine of the foregoing re action is replaced by trimethylamine, dimethylethylamine, Molecular weight, dinner 236 209 methyldiethylamine, triethylamine, dimethyl - n - butyl This complex doubtless also exists as a dimer in ben O amine, dimethylisobutylamine, dimethyl-n-octylamine, di Zene solution. methyl-n-nonylamine, N,N-dimethylbenzylamine, N,N-di When the trimethylamine of the beryllium hydride com methylcyclohexylamine, N-methyl pyrrollidine, N-ethyl plex is replaced by dimethylethylamine, methyldiethyl pyrrolidine or N-methyl piperidine, similar results are ob amine, triethylamine, dimethyl-n-propyl amine, dimethyl tained. Furthermore, when the beryllium chloride of the n-hexyl amine, dimethyl-n-decyl amine or dimethyl-n-do above reaction is replaced by beryllium bromide or beryl decyl amine, similar results are obtained. lium iodide, similar results are obtained. Comparison of Examples 1 and 2 shows that in the In this process, excess amine is employed as reaction former the amine components of the two reactants were medium. The beryllium hydride complex is soluble in this different whereas in the latter they were identical. Nor medium whereas the beryllium chloride is insoluble. In mally it is desirable that the amines be identical since, if view of the solubility of one of the reactants, the ball they are different, the product is not pure but a mixture. milling operation of the above example can be replaced However, because of its volatility, trimethylamine can be by any form of vigorous agitation. However the reaction used as in Example 1 with any significantly less volatile solvent is not limited to an excess of the amine of the amine to produce a substantially pure product. hydride complex. A mixture of the amine in any propor When the amine hydrochlorides of the above examples tion with a liquid aromatic hydrocarbon can be used. are replaced by the corresponding bromine and iodine Suitable hydrocarbons include benzene, toluene, the Xyl derivatives, similar results are obtained. enes, mesitylene, p-cymene, pseudocumene, cumene and The reactions of the amine-complex process are nor mixtures thereof. mally carried out in a solvent, which may be simply an The berryllium chloride and the hydride complex re excess of the pure amine reactant, but may also be an 30 actants of the present process can be combined in a wide aromatic hydrocarbon or a saturated aliphatic hydrocar variety of proportions ranging from a 100 percent or bon or a mixture thereof, which is liquid under reaction greater excess of the beryllium chloride reactant to a 100 conditions. The solvents should be dry and free of traces percent or greater excess of the beryllium hydride com of primary and secondary amines. The reactants of this plex reactant. For reasons of economy and ease of manip process can be employed in proportions ranging from 35 ulation, an approximately stoichiometric proportion is stoichiometric to a 10 percent or greater excess of the preferred.
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