Finally, macrocycle 3 was synthesized in a similar manner as macrocycle 1 by condensation of bis-O-hydroxylamine 16 with diacylchloride 17 41 (Scheme 3). The bis-O-hydroxylamine was obtained in three steps by bromomethylation of 1,2-diethoxybezene 12, followed by nucleophilic substitution by N-hydroxyphthalimide 14 42 on 13 and subsequent hydrazinolysis. Notably, for this macrocyclization, the rate of addition had little effect on the yield of the reaction and increasing the equivalents of TBACl beyond 10 only had a negligible effect on the yield. Moreover, the addition of other templates such as TBAH2PO4 or TBA2H2P2O7 gave lower yields compared to the 55% yield obtained with TBACl. Scheme 3. Synthesis of macrocycle 3.