Lithium aluminum hydride benzylic halide reduction

A thio-substituted, quaternary ammonium salt can be synthesized by the Michael addition of an alkyl thiol to acrylamide in the presence of benzyl trimethyl ammonium hydroxide as a catalyst [793-795]. The reaction leads to the crystallization of the adducts in essentially quantitative yield. Reduction of the amides by lithium aluminum hydride in tetrahydrofuran solution produces the desired amines, which are converted to desired halide by reaction of the methyl iodide with the amines. The inhibitor is useful in controlling corrosion such as that caused by CO2 and H2S. 

Halides and tosylates. Trevoy and W. G. Brown found that lithium aluminum hydride reduces benzyl iodide and benzyl bromide in high yield at 35° in either diethyl ether or tetrahydrofurane. In tetrahydrofurane at 65°, benzyl chloride and 1 -bromodecane are reduced to toluene and to n-decane, both in 72% yield. Johnson, Blizzard, and Carhart found that lithium aluminum hydride reacts more sluggishly than in other reductions and presented experimental evidence that not all four hydrogen atoms possess adquate reactivity toward alkyl halides. Thus the reaction probably proceeds in at least two steps, the first of which is much more rapid than... 

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