Issue 39, 2009

Two-coordinate, homoleptic manganese(ii) primary terphenyl amido complexes: the effects of secondary coordination on geometry and Lewis base complexation

Abstract

The synthesis and characterization of the mononuclear manganese primary amido complex Mn{N(H)Ar#}2 (1), its Lewis base adducts Mn{N(H)Ar#}2(L) (Ar# = C6H3-2,6-(C6H2-2,4,6-Me3)2; L = THF (2), and C5H5N (3)), and Mn{N(H)Ar*}2 (4) (Ar* = C6H3-2,6-(C6H2-2,4,6-iPr3)2) are described. Complex 1 was prepared by the reaction of MnCl2 with two equivalents of LiN(H)Ar# in benzene. X-Ray crystallography showed that it had a quasi-two-coordinate strongly bent geometry with Mn–N = 1.979(3) Å, N–Mn–N = 138.19(9)° and secondary Mn⋯C(aryl ring) interactions. In contrast, complex 4, which was prepared by the same route as 1, has an almost linear geometry with a wide N–Mn–N angle of 176.1(2)°. The complexes 1 and 4 are the first structurally characterized homoleptic primary amido derivatives of manganese. Complex 1 did not react with THF or pyridine, but its THF complex 2 could be formed by the reaction of MnI2(THF)2 with two equivalents of LiN(H)Ar#. Similarly, complex 3 was prepared either by the direct reaction of MnCl2 with LiN(H)Ar# in hexanes in the presence of pyridine, or by reaction of the THF complex 2 with excess pyridine. Attempts to form Lewis base complexes of 4 by similar routes led to the recovery of unreacted 4. The results suggested that reaction with Lewis bases is prevented by secondary interactions (1) or steric effects (4). Magnetic studies show that the manganese(II) ions in 1–4 have high spin configurations with S = [fraction five-over-two] and small zero-field splittings, D, of ca.±1.5 to ±3 cm−1.

Graphical abstract: Two-coordinate, homoleptic manganese(ii) primary terphenyl amido complexes: the effects of secondary coordination on geometry and Lewis base complexation

Supplementary files

Article information

Article type
Paper
Submitted
18 Jun 2009
Accepted
15 Jul 2009
First published
21 Aug 2009

Dalton Trans., 2009, 8349-8355

Two-coordinate, homoleptic manganese(II) primary terphenyl amido complexes: the effects of secondary coordination on geometry and Lewis base complexation

C. Ni, B. Rekken, J. C. Fettinger, G. J. Long and P. P. Power, Dalton Trans., 2009, 8349 DOI: 10.1039/B911978G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements