Addition of Allylzinc to α-Amino Acid-Derived Imines: Synthesis of Diamino Alcohols by Hydroboration.

Imines obtained by condensation of Z-protected or Boc-protected α-amino aldehydes with α-amino tert-butyl esters or with O-silyl-protected amino alcohols were reacted with preformed allyl zinc yielding homoallylamines with yields around 50% and selectivities ranging from 50:50 to 90:10. Hydroboration of the terminal double bond furnished diamino alcohols with yields up to 97%. The configuration of the substrates was determined by X-ray-crystallographic analysis of a hydroboration product and comparison of physical data.