Oxygen atom transfer reactions from sterically encumbered brominated (oxo)manganese(V) corroles to styrene

Seven A 3 - and trans -A 2 B manganese(III) corroles ( 1–7- Mn) differing widely in their electronic and steric features were synthesized and transformed to their corresponding β -brominated manganese(III) corroles derivatives ( 1a–7a- Mn). Their corresponding (oxo)manganese(V) corroles 1–7- Mn(oxo) and 1a–7a- Mn(oxo) were further prepapred by treating with iodosylbenzene (PhIO). The reactivity for the oxygen atom transfer from 1–7- Mn(oxo) to styrene followed the order of 1- Mn(oxo) > 2- Mn(oxo) > 7- Mn(oxo) > 4- Mn(oxo) > 3- Mn(oxo) > 6- Mn(oxo) ≈ 5- Mn(oxo). The same pattern was observed for their β -brominated analogs 1a–7a- Mn(oxo), albeit their reactivity was remarkably higher. The steric protection of Mn V ≡ O moiety by ortho – ortho ′-dibromophenyl substituents was found to enhance the stability of (oxo)manganese(V) corroles significantly.