The α,α′-stabilized carbanion complexes [(PhSO2)2CHLi·THF]
1, [(PhSO2)2CHNa·THF]
2 and [(PhSO2)2CHK]
3 were prepared by the direct deprotonation of bis(phenylsulfonyl)methane I in THF with one molar equivalent of MeLi, BuNa and BnK respectively. The geminal dianionic complexes [(PhSO2)2CLi2·THF]
4, [(PhSO2)2CNa2·0.55THF]
5 and [(PhSO2)2CK2]
6 were similarly prepared by the reaction of I with two molar equivalents of MeLi, BuNa and BnK respectively in THF. NMR and MS solution studies of 1–3 are consistent with the formation of charge-separated species in DMSO media. Solutions studies of 4–6, in conjunction with trapping experiments, indicate that the dianions deprotonate DMSO and regenerate the monoanions 1–3. Crystallographic analysis of 1 revealed a 1D chain polymer in which the metal centers are chelated by the bis(sulfonyl) ligands and connect to neighboring units through Li–O(S) interactions. An unexpected feature of 1 is that the polymeric chains are homochiral, since the chelating ligands of the backbone adopt the same relative configuration. Also, the phenyl substituents of each chelate in 1 are oriented in a cisoid manner. The sodium derivative 2 adopts a related solid-state structure, where enantiomeric pairs of chains combine to give a 1D ribbon motif. The lithium bis(phenylsulfonyl)imides [(PhSO2)2NLi·THF]
9 and [(PhSO2)2NLi·Pyr2]
10 were also prepared and structurally characterized. In the solid state 9 has a similar connectivity to that found for 1 but with heterochiral chains. In comparison, the more highly solvated complex 10 forms a 1D polymeric arrangement without chelation of the ligands and with the phenyl substituents oriented in a transoid fashion.
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