Unexpected 1,2 syn diastereoselectivity in the three-component ‘aza Sakurai–Hosomi’ reaction

Abstract The three-component ‘aza Sakurai–Hosomi’ reaction performed on (±) O-protected mandelic aldehydes provided the unexpected syn hydroxy homoallylamines 2 and 2d as the major adducts. An intramolecular chelated transition state via a hydrogen bond is proposed to explain this 1,2 syn diastereoselectivity.