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Sc3CH@C80: selective (13)C enrichment of the central carbon atom.

ABSTRACT: Sc3CH@C80 is synthesized and characterized by (1)H, (13)C, and (45)Sc NMR. A large negative chemical shift of the proton, -11.73 ppm in the Ih and -8.79 ppm in the D5h C80 cage isomers, is found. (13)C satellites in the (1)H NMR spectrum enabled indirect determination of the (13)C chemical shift for the central carbon at 173 ± 1 ppm. Intensity of the satellites allowed determination of the (13)C content for the central carbon atom. This unique possibility is applied to analyze the cluster/cage (13)C distribution in mechanistic studies employing either (13)CH4 or (13)C powder to enrich Sc3CH@C80 with (13)C.

SUBMITTER: Junghans K

PROVIDER: S-EPMC4902131 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Sc3CH@C80: selective (13)C enrichment of the central carbon atom.

Junghans Katrin K Rosenkranz Marco M Popov Alexey A AA

Chemical communications (Cambridge, England) 20160501 39

Sc3CH@C80 is synthesized and characterized by (1)H, (13)C, and (45)Sc NMR. A large negative chemical shift of the proton, -11.73 ppm in the Ih and -8.79 ppm in the D5h C80 cage isomers, is found. (13)C satellites in the (1)H NMR spectrum enabled indirect determination of the (13)C chemical shift for the central carbon at 173 ± 1 ppm. Intensity of the satellites allowed determination of the (13)C content for the central carbon atom. This unique possibility is applied to analyze the cluster/cage ( ...[more]

PMID: 27109443

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