We next wished to examine the effect of various sulfamate N-substituents on the efficiency of cyclization (Scheme 2). Our optimized protocol was compatible with a variety of Nalkyl substituents, including methyl, n-hexyl, and cyclohexyl (Scheme 2, Entries 2-4). We were pleased that cyclization was possible even with bulky N-aryl groups. With N-phenyl sulfamate 9, the reaction time had to be extended from 48 h to 60 h for optimal product yield (Scheme 2, Entry 5). In contrast, with N-tolyl and N-p-OMe-phenyl sulfamates 11 and 13, a normal reaction time of 48 h was sufficient (Scheme 2, Entries 6-7).