The diazotisation of (±)-1-(2-amino-3-benzyloxy-4-methoxybenzyl)-1,2,3,4-tetrahydro-6,7-dimethoxy-2-methylisoquinoline (VIII) followed by the thermal decomposition of the resulting diazonium salt, gave (±)-salutaridine (II)[or (±)-sinoacutine], which was converted into (±)-thebaine (III). The 2-aminobenzylisoquinoline (VIII) was resolved, and the (–)- and (+)-enantiomers (VIIIa and b) were used for the syntheses of salutaridine (IIa), sinoacutine (IIb), and thebaine (IIIa) and its antipode (IIIb). This work also constitutes the fifth total synthesis of morphine (I).