Process for producing polyamine boranes

Abstract

This invention relates to a process for producing tertiarydiamine-boranes by reacting a tertiary diamine with a borohydride in the presence of a carboxylic or mineral acid source. Water is included in the reaction medium in a catalytic amount but insufficient for forming two phases. Excellent selectivity to tertiary diamine-boranes is achieved.

What is claimed is: 
     
       1. In a process for producing amine boranes by the reaction of a metal borohydride with a tertiary amine in the presence of an inert organic solvent and a protic acid source, the improvement for enhancing formation of a borane complex of a polyamine containing a tertiary nitrogen atom as the tertiary amine which comprises: effecting the reaction in the presence of water wherein the water is present in a catalytically effective amount but insufficient for forming two phases.   
     
     
       2. The process of claim 1 wherein the water is present in an amount of from 0.5% based upon the weight of the solvent to the saturation level. 
     
     
       3. The process of claim 2 wherein the acid source is a carboxylic acid wherein the carboxylic acid has from 2-10 carbon atoms. 
     
     
       4. The process of claim 3 wherein said polyamine containing a tertiary nitrogen atom is a cyclized diamine. 
     
     
       5. The process of claim 4 wherein said cyclized diamine is triethylenediamine or an alkyl derivative thereof. 
     
     
       6. The process of claim 5 wherein said cyclized diamine is methyltriethylenediamine. 
     
     
       7. The process of claim 3 wherein said polyamine is a methylated or ethylated derivative of diethylenetriamine or triethylenetetramine. 
     
     
       8. The process of claim 3 wherein said polyamine is methylated ethylenediamine or methylated propanediamine. 
     
     
       9. The process of claim 2 wherein said acid source is a mineral acid carried in an organic medium and said amine is triethylenediamine or methyltriethylenediamine. 
     
     
       10. A process for forming borane complex of triethylenediamine and methyl-triethylenediamine which comprises reacting methyl-triethyleneamine or triethylenediamine with sodium borohydride in the presence of C 2-4  carboxylic acid and water wherein the water is provided at a level of from 0.5% by weight of the amine to the saturation level, the reaction being carried out at a temperature from about -25° to 30° C. and a pressure ranging from atmospheric to 50 psig. 
     
     
       11. The process of claim 10 wherein said carboxylic acid is acetic acid.