Utilization of industrial waste materials, 5. Synthesis of new, chiral 1,3,2‐oxazaphospholidine‐borane complexes and attempts to apply them in the stereoselective synthesis

New, chiral 1,3,2‐oxazaphospholidine‐borane complexes 3a‐b and 8a‐d were synthesized from the β‐amino alcohols 1a‐b and 6a‐d . The borane complexes 3, 8a, 8c , and 8d were allowed to react with different organolithium compounds and afforded the corresponding aminophosphane‐borane complexes 4a–c and 9a‐g . Acid methanolysis of those complexes led to the formation of the phosphinite‐borane complexes 5a‐c. This is a further example of the utilization of the industrial waste material ( all‐R )‐2‐azabicyclo‐[3.3.0]octane‐3‐carboxylic acid. The catalytic efficiency of the chiral 1,3,2‐oxazaphospholidine‐borane complexes 3a, 3b , and 8c was examined in the enantioselective borane reduction of some ketones.