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Updated: May 27, 2026

Chemoselective Preparation of 1-Iodoalkynes, 1,2-Diiodoalkenes, and 1,1,2-Triiodoalkenes Based on the Oxidative Iodination of Terminal Alkynes
Published on: September 12, 2018
A second monoclinic polymorph of bis-(2,2'-bipyridine-κN,N')diiodido-manganese(II)
1School of Applied Chemical Engineering, The Research Institute of Catalysis, Chonnam National University, Gwangju 500-757, Republic of Korea.
Abstract:
The Mn(II) ion in the title complex, [MnI(2)(C(10)H(8)N(2))(2)], is six-coordinated in a distorted cis-N(4)I(2)Mn octa-hedral environment by four N atoms of the two chelating 2,2'-bipyridine ligands and two iodide anions. As a result of the different trans effects of the N and I atoms, the Mn-N bonds trans to the I atom are slightly longer than the Mn-N bonds trans to the N atom. The dihedral angle between the approximately planar ligands [maximum deviation = 0.064 (7) Å] is 75.0 (1)°. Numerous inter- and intra-molecular π-π inter-actions between the pyridyl rings are present, the shortest centroid-centroid distance being 3.905 (5) Å. The structure reported herein represents a new monoclinic polymorph of the previously reported monoclinic (P2(1)/c) form [Ha (2011 ▶). Z. Kristallogr. New Cryst. Struct.226, 187-188].
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