(3a)-(3d) affords the corresponding exocyclic bromides (4a)-(4d). The procedure provides a novel alternative route to N-(α-haloalkyl)-substituted lactams, which are of particular interest in the synthesis of β-lactam antibiotics.
N-取代的内酰胺(3a)-(3d)的区域选择性卤化得到相应的环外
溴化物(4a)-(4d)。该方法为N-(α-卤代烷基)-取代的内酰胺提供了一种新颖的替代途径,这在β-内酰胺抗生素的合成中特别有意义。