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The title complex, (1,4,7,10,13,16-hexaoxacyclooctadecane-1κ6O)(μ-oxalato-1κ2O1,O2:2κ2O1′,O2′)triphenyl-2κ3C-potassium(I)tin(IV), [KSn(C6H5)3(C2O4)(C12H24O6)] or K[18-Crown-6][(C6H5)3SnO4C2], was synthesized. The complex consists of a potassium cation coordinated to the six oxygen atoms of a crown ether molecule and the two oxygen atoms of the oxalatotriphenylstannate anion. It crystallizes in the monoclinic crystal system within the space groupP21. The tin atom is coordinated by one chelating oxalate ligand and three phenyl groups, forming acis-trigonal–bipyramidal geometry around the tin atom. The cations and anions form ion pairs, linked through carbonyl coordination to the potassium atoms. The crystal structure features C—H...O hydrogen bonds between the oxygen atoms of the oxalate group and the hydrogen atoms of the phenyl groups, resulting in an infinite chain structure extending alonga-axis direction. The primary inter-chain interactions are van der Waals forces.
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β C–H di-halogenation via iterative hydrogen atom transfer
A radical relay strategy for mono- and di-halogenation (iodination, bromination, and chlorination) of sp3C–H bonds has been developed. This first example of double, geminal C–H functionalization is enabledviaiterative, hydrogen atom transfer (HAT) byin situgenerated imidate radicals.
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- Award ID(s):
- 1654656
- PAR ID:
- 10074246
- Publisher / Repository:
- Royal Society of Chemistry (RSC)
- Date Published:
- Journal Name:
- Chemical Science
- Volume:
- 9
- Issue:
- 19
- ISSN:
- 2041-6520
- Page Range / eLocation ID:
- 4500 to 4504
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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