A novel synthetic route to enantiomerically pure 1-benzyltetrahydroisoquinolines (1) was developed via the reaction of oxazolo[2, 3-a]tetrahydroisoquinoline (5) with benzyltriisopropoxytitanium compounds (10). This method was applied to the synthesis of (S)-trimetoquinol (1c; a bronchodilator).