| Abstract
| - The structures of three ortho-lithiated phenyloxazolines, the parent (1), the para-tert-butyl analogue(2), and the para-chloro analogue (3), were studied in solution. All three compounds are mixtures ofmonomers and dimers in THF/ether mixed solvents, with 2 the most aggregated and 3 the least. They areconverted to monomers with HMPA and PMDTA. In the PMDTA complexes, the lithium appears tostill be chelated to the oxazoline ring. Single-crystal X-ray structures were obtained for 1 and 2. Both arecentrosymmetric dimers of B-type (each lithium coordinated to one oxazoline ring).
- The structures of several ortho-lithiated phenyloxazolines in THF/ether mixed solvents were studied using low-temperature, multinuclear NMR spectroscopy and determined to be mixtures of monomers and dimers. X-ray diffraction studies on single crystals obtained from THF solutions revealed centrosymmetric dimer structures in which the oxazoline nitrogen atoms are oriented toward the lithium atoms and within bonding distance (2.024(3) Å).
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