Ethylenediamine borane reductions with

Devaky and Rajasree have reported the production of a polymer-bound ethylenediamine-borane reagent (63) (Fig. 41) for use as a reducing agent for the reduction of aldehydes.87 The polymeric reagent was derived from a Merrifield resin and a 1,6-hexanediol diacrylate-cross-linked polystyrene resin (HDODA-PS). The borane reagent was incorporated in the polymer support by complexation with sodium borohydride. When this reducing agent was used in the competitive reduction of a 1 1 molar mixture of benzaldehyde and acetophenone, benzaldehyde was found to be selectively reduced to benzyl alcohol. 

The tetratoluenesulfonamide may be prepared in five simple steps from ethylenediamine by reaction with thiodiglycollic anhydride in CH2CI2, ethanolysis, ammonolysis, borane reduction and tosylation12. 

The precursor tetratosylamide 22 may be prepared in five steps from ethylenediamine. The reaction sequence (Scheme 3.7) involves diacylation of ethylenediamine with 3-thiadiglycollic anhydride, followed by esterification, ammonolysis, borane reduction and toluenesulfonylation.12 This stepwise synthesis of the desired tetratoluenesulfonamide involving a simple chain elongation strategy is reminiscent of the syntheses of large ring aza-oxa crowns (e.g. [24]-N404) discussed in Chapter 2. 

Solid state reduction of alkyl aryl ketone 8 in an inclusion complex with the chiral host 10 with borane-ethylenediamine complex 2BH3-NH2CH2CH2NH2 gave optically active alcohol 9 in the optical and chemical yields summarized in Table 15-3 [7],... 

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