25Mg NMR

The alloy Zni xMgxO has also been studied by NMR [296]. At levels of up to 15% Mg only weak effects are seen upon the 67Zn (/ = 5/2) MAS-NMR spectrum, but the 25Mg (/ = 5/2) resonance is greatly shifted to lower frequencies. 

Table 6. Summary of solid-state NMR interaction parameters of 25Mg... 

Fig. 22. 220-MHz NMR spectra (N-CH3 region) of CycMSare) in DMSO-de with or without RbSCN. Molar ratio of RbSCN/cyclic peptide (a), 0 (b), 5.35 (c), 35.65. Concentration of Cyclo-tSare). 25mg/ml...

A solution of enantioenriched (5,5)-benzodiphosphetane (25mg, O.lOmmol, er=10 l) in 5mLofCHp2 was treated with methyl triflate (11 pL, O.lOmmol). After 1 h, the solvent was removed in vacuo and the residue was redissolved in Etp (5 mL). The solution was cooled to -78 °C and treated with MeMgBr (34pL of a 3.0M solution in Et O, O.lOmmol) and then allowed to warm to room temperature. After stirring for 2h, a white precipitate had formed, and the P NMR spectrum showed conversion to BenzP. The solvent was removed in vacuo, then the residue was dissolved in Et O, and the solution was passed over a pipet silica ping. The solvent was removed under vacuum to give 13 mg (46%) of an oily white residue. 

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