7-Methyl-2,3,4,5-tetrahydro-1,4-oxazepin-5-one and the dioxepinone analogue: diastereofacial selectivity in catalytic hydrogenation and the explanation
7-Methyl-2,3,4,5-tetrahydro-1,4-oxazepin-5-one and the dioxepinone analogue: diastereofacial selectivity in catalytic hydrogenation and the explanation