C([Si]([O:8][C:9]1[CH:14]=[CH:13][C:12]([Cl:15])=[CH:11][C:10]=1[Cl:16])(C)C)(C)(C)C.C([Li])(CC)C.CN(C)[CH:24]=[O:25].[C:27](O)(=O)C>O1CCCC1.O>[Cl:16][C:10]1[C:9]([O:8][CH3:27])=[CH:14][CH:13]=[C:12]([Cl:15])[C:11]=1[CH:24]=[O:25]Dissolve tert-Butyl-(2,4-dichloro-phenoxy)-dimethyl-silane (48.4 g, 175 mmol) in tetrahydrofuran (575ml) and cool to −78° C. Add sec-butyl lithium (1.4M, 131 ml, 183 mmol) slowly at −78° C. and stir at −78° C. for 30 minutes. Add N,N-dimethylformamide and stir at −78° C. for 1.5 hours. Pour reaction mixture into acetic acid in water (1:12, 830 ml) and stir warming to room temperature. Extract with ether, wash with water, brine dry over sodium sulfate, filter and concentrate to yield a mixture of the title compound and TBS protected analog. Slur in hexanes and filter to yield 15 g (45%) of 2,6-dichloro-3-hydroxy-benzaldehyde.
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