Patent GB-774516-A (GB)
Title: The manufacture of organic compounds of aluminium
IPC: C07F5/06
Filed: 1953-04-20
Abstract: The invention comprises alkylaluminium hydrides of the general formul RAlH2 and R2AlH, wherein R represents an alkyl radical containing at least 2 carbon atoms, and alkali metal alkylaluminium hydrides of the general formul  (R2AlH2)Z and (RAlH3)Z, wherein R represents an alkyl radical and Z represents an alkali metal, and the preparation of alkylaluminium hydrides of the general formula AlHXY, wherein X represents an alkyl radical and Y represents hydrogen or an alkyl radical, and complex compounds thereof with alkali metal hydrides, by reacting an alkylaluminium dihalide or a dialkylaluminium halide with an alkali metal hydride.  A dialkylaluminium hydride is obtained by reacting a dialkylaluminium halide with an alkali metal hydride in equimolecular proportions, and an alkali metal dialkylaluminium dihydride is obtained by reacting one molar proportion of a dialkylaluminium halide with at least 2 molar proportions of an alkali metal hydride.  An alkylaluminium dihydride is obtained by reacting an alkylaluminium dihalide with an alkali metal hydride in a molar ratio of 1:2, and an alkali metal alkylaluminium trihydride is obtained by reacting 1 molar proportion of an alkylaluminium dihalide with at least 3 molar proportions of an alkali metal hydride.  The dialkylaluminium hydrides may also be obtained by reacting 1 molar proportion of a dialkylaluminium halide with more than 1 molar proportion of an alkali metal hydride to form an alkali metal dialkylaluminium dihydride which is then converted to the dialkylaluminium hydride by reaction with additional dialkylaluminium halide in a molar ratio of 1:1, or by reacting an alkali metal dialkylaluminium dihydride with a dialkylaluminium halide in a molar ratio of 1:1.  The alkylaluminium dihydrides may also be obtained by reacting 1 molar proportion of an alkylaluminium dihalide with more than 2 molar proportions of an alkali metal hydride to form an alkali metal alkylaluminium trihydride which is then converted to the alkylaluminium dihydride by reaction with additional alkylaluminium dihalide in a molar ratio of 2:1, or by reacting an alkali metal alkylaluminium trihydride with an alkylaluminium dihalide in a molar ratio of 2:1.  In the above reactions using an alkali metal hydride, it is preferable to suspend the alkali metal hydride in an inert liquid medium which is then heated together with a solution of the alkylaluminium halide in said medium; this process may be modified in that a preformed alkylaluminium hydride is introduced into the suspension of alkali metal hydride prior to the reaction with the alkylaluminium halide.  In the examples diethylaluminium hydride is prepared by reacting diethylaluminium chloride with lithium or sodium hydride; dipropyllithium aluminium dihydride is prepared by reacting lithium hydride with dipropylaluminium chloride (di-n-hexylaluminium hydride is prepared by a similar method); lithium aluminium isobutyl trihydride is prepared by reacting isobutylaluminium dichloride with lithium hydride; and sodium dipropylaluminium dihydride is prepared by reacting dipropylaluminium chloride with sodium hydride.  Dipropyl aluminium chloride is prepared by reacting tripropylaluminium and aluminium chloride.  Isobutylaluminium dichloride is prepared by a similar method.  Dimerized mono-olefins are prepared by the process described in Specification 742,642 using as initiators dialkylaluminium hydrides, alkylaluminium dihydrides, alkali metal dialkylaluminium dihydrides and alkali metal alkylaluminium trihydrides.  Specifications 713,081 and 763,824 also are referred to.