Bis(benzene-1,2-diolato-κ 2 O , O ′)bis(dimethyl sulfoxide-κ O )titanium(IV), [Ti(C 6 H 4 O 2 ) 2 (C 2 H 6 OS) 2 ], crystallizes with two crystallographically independent molecules in the space group P 2 1 / c emulating orthorhombic Pbca symmetry (β = 90.0445 (9)°]. The two molecules are related by pseudo-glide symmetry, broken by modulation of each one catecholate and dimethyl sulfoxide (DMSO) ligand. Twinning by pseudomerohedry was observed [twin ratio 0.5499 (7):0.4401 (7)]. Complex 3 was obtained by heating of diprotonated titanium tris-catecholate precursor 2 H in DMSO, by formal displacement of a catechol molecule by two DMSO molecules. Complex 3 is just the second heteroleptic, mono-nuclear, neutral bis-catecholate complex with TiO 6 metal coordination, the only other one being its bis-DMF analogue 6 . The two molecules of 3 exhibit a distorted octahedral geometry. The geometry and distortions from ideal symmetry of 3 are discussed and compared to 6 and to cationic tris-catecholate titanium complexes.
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In situ formation and solid-state oxidation of a triselenane NSeN-pincer MOF
Controlled partial decomposition of 2-selenonicotinic acid in the presence of Co 2+ or Ni 2+ resulted in the in situ formation of an unusual MOF based on triselenane ligands (RSeSeSeR) coordinated to M 2+ centers as NSeN-pincers. Post-synthetic oxidation by treatment with aqueous H 2 O 2 facilitates its solid-state conversion into a RSeO 2 − molecular coordination complex, which was tracked via powder X-ray diffraction studies and by single-crystal structural resolution of the final product.
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- Award ID(s):
- 1905701
- PAR ID:
- 10179590
- Date Published:
- Journal Name:
- Chemical Communications
- Volume:
- 56
- Issue:
- 8
- ISSN:
- 1359-7345
- Page Range / eLocation ID:
- 1286 to 1289
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Multienzyme complexes have the potential for green catalysis of sequential reactions. The
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/c9cc07851g
