Wydział Chemii

Anna Młodzianowska

Lechosław Latos-Grażyński

Ludmiła Szterenberg

Marcin Stępień

2007

Inorganic Chemistry

46

6950-6957

10.1021/ic700647v

Naukowa

Angielski

Artykuł

Boron(III) has been inserted into N-confused porphyrin, (NCPH)H₂ (1), and N-fused porphyrin, (NFP)H (2). The reaction of dichlorophenylborane and 1 yields σ-phenylboron N-confused porphyrin (4). The boron atom is bound by two pyrrolic nitrogen atoms and the σ-phenyl ligand. The N-confused pyrrole ring is not involved in the direct coordination because the C(21)−H fragment remains intact. A reaction between PhBCl₂ and N-fused porphyrin produces σ-phenylboron N-fused porphyrin (3⁺). 4 converts quantitatively into 3⁺ under protonation. In σ-phenylboron N-fused porphyrin [(NFP)BPh]Cl, the coordinating environment of boron(III) resembles a distorted trigonal pyramid, with the nitrogen atoms occupying equatorial positions and with the phenyl ligand lying at the unique apex. Boron(III) is displaced by 0.547(4) Å from the N₃ plane. The B−N distances are as follows:  B−N(22), 1.559(4) Å; B−N(23), 1.552(4) Å; B−N(24), 1.568(4) Å; B−C_ipsoPh, 1.621(4) Å. 3⁺ can be classified as a boronium cation considering a filled octet and a complete coordination sphere. 3⁺ is susceptible to alkoxylation at the inner C(9) carbon atom, yielding 5-OR. The addition of acid results in protonation of the alkoxy group and elimination of alcohol, restoring the original 3⁺. Density functional theory has been applied to model the molecular and electronic structure of 4, 3⁺, and syn and anti isomers of methoxy adducts 5-OMe.

https://doi.org/10.1021/ic700647v

https://www.acs.org/content/acs/en.html