Phosphetane boranes

In most cases, the resulting phosphetanes are isolated as borane complexes, which are formed in situ just after the reaction however, the borane can be easily removed by reaction with l,4-diazabicyclo[2.2.2]octane (DABCO). 

There is a single example of enantioselective deprotonation of phosphetane derivatives, reported by Imamoto and co-workers.They prepared a Cj-diphosphine borane (abbreviated as DiSquareP ) by enantioselective deprotonation of 1-tert-butylphosphetane borane, 114 (Scheme 5.46). 

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