Regioselective Carbon‐Halogen Bond Formation in the Reaction of Ag(III)N‐Confused Porphyrin Complex with HCl or HBr

Abstract

A facile inner halogenation of Ag(III) NCP complex1is reported. Treatment of1with 2NHCl and 1NHBr gave2and4, respectively. A demetallized product3was formed as a trace side product when dilute acids were applied and as a predominant product when treated with concentrated acids. The importance of the C3‐ethoxy group for the halogenation reactions was experimentally indicated. Treatment of1with 4NH2SO4gave carbaporpholactam6in good yield. Halide anions are suggested to accelerate the demetallation reaction of1.

Organometallic chemistry confined within a porphyrin-like framework

“…The metal centre can be removed through acidification. 99 Interestingly, when the complex is substituted with an ethoxy group at the C(3) position, demetallation is accompanied by the halogenation of the C(21) atom coming from the HX molecule.…”

Creation from Confusion and Fusion in the Porphyrin World─The Last Three Decades of N-Confused Porphyrinoid Chemistry

“…195 When 132 was treated with 2 N HCl or 1 N HBr, demetalation and halogenation proceeded to give 21-halogenated NCP 133a−b in 90−91% yields, while pure demetalation could be achieved with concentrated H 2 SO 4 to give 134 in 90% yield. 196 3.3.6. Phosphorylation.…”

“…The treatment of 121 with alcohol in the presence of AgOCOCF 3 caused alkoxylation at the 3-position to give the monoalkoxylated products 132 in 70–81% yields (Scheme ). When 132 was treated with 2 N HCl or 1 N HBr, demetalation and halogenation proceeded to give 21-halogenated NCP 133a – b in 90–91% yields, while pure demetalation could be achieved with concentrated H 2 SO 4 to give 134 in 90% yield …”

Oxidation of 3‐Oxo‐N‐Confused Porphyrin with PIFA: Inner and meso Functionalizations

“…Shimizu and co‐workers synthesized a series of interesting ligands through Schiff base reaction of 3‐oxo‐N‐confused porphyrin [17a] . We are interested in studying the reactivities of NCP [11,20b,21] . For example, based on the calculation result that this C=N bond is partially isolated from the 18 π‐electron macrocyclic conjugation system, we developed a CF 3 COOAg‐catalyzed alkoxylation at the outer C=N position of Ag(III) NCPs [21] .…”