The synthesis and the crystal structure of 1 H -imidazole-1-methanol, C 4 H 6 N 2 O, are described. This compound comprises an imidazole ring with a methanol group attached at the 1-position affording an imine nitrogen atom able to receive a hydrogen bond and an alcohol group able to donate to a hydrogen bond. This imidazole methanol crystallizes with monoclinic ( P 2 1 / n ) symmetry with three symmetry-unique molecules. These three molecules are connected via O—H...N hydrogen bonding in a head-to-tail configuration to form independent three-membered macrocycles.
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Crystal structure of 1-(2,6-diisopropylphenyl)-1 H -imidazole
The crystal structure of the title compound, C15H20N2orDippIm, is reported. At 106 (2) K, the molecule has monoclinicP21/c symmetry with four molecules in the unit cell. The imidazole ring is rotated 80.7 (1)° relative to the phenyl ring. Intermolecular stabilization primarily results from close contacts between the N atom at the 3-position on the imidazole ring and the C—H bond at the 4-position on the neighboringDippIm, with aryl–aryl distances outside of the accepted distance of 5 Å for π-stacking.
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- Award ID(s):
- 1847926
- PAR ID:
- 10537821
- Publisher / Repository:
- IUCr
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 79
- Issue:
- 11
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 1079 to 1082
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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The masked Ti( ii ) synthon ( Ket guan)(η 6 -Im Dipp N)Ti ( 1 ) oxidatively adds across thiophene to give ring-opened ( Ket guan)(Im Dipp N)Ti[κ 2 - S (CH) 3 C H] ( 2 ). Complex 2 is photosensitive, and upon exposure to light, reductively eliminates thiophene to regenerate 1 – a rare example of early-metal mediated oxidative-addition/reductive-elimination chemistry. DFT calculations indicate strong titanium π-backdonation to the thiophene π*-orbitals leads to the observed thiophene ring opening across titanium, while a proposed photoinduced LMCT promotes the reverse thiophene elimination from 2 . Finally, pressurizing solutions of 2 with H 2 (150 psi) at 80 °C leads to the hydrodesulphurization of thiophene to give the Ti( iv ) sulphide ( Ket guan)(Im Dipp N)Ti(S) ( 3 ) and butane.more » « less
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