[CH3:1][Li].[CH3:3][C:4]1[CH:11]=[C:10]([N+:12]([O-:14])=[O:13])[CH:9]=[CH:8][C:5]=1[CH:6]=[O:7]>C(OCC)C.[Ti](Cl)(Cl)(Cl)Cl>[CH3:3][C:4]1[CH:11]=[C:10]([N+:12]([O-:14])=[O:13])[CH:9]=[CH:8][C:5]=1[CH:6]([OH:7])[CH3:1]Following the General Procedure of Description 8, MeTiCl3 was freshly prepared prior to use from commercial titanium tetrachloride (TiCl4) (4.73 mL, 8.17 g, 43.1 mmol) and methyl lithium (MeLi) (1.6 M in Et2O, 26.9 mL, 43.0 mmol) in anhydrous diethyl ether (Et2O) (230 mL). A solution of 2-methyl-4-nitro-benzaldehyde (7b) (7.11 g, 43.0 mmol) in anhydrous Et2O (200 mL) was added. Aqueous work-up afforded 7.0 g (90% yield) of the target compound (7c) as a yellow solid. The material was of sufficient purity to be used directly in the next step without further isolation and purification procedures. Rf: ˜0.24 (EtOAc/Hxn=1:2 v/v). 1H NMR (300 MHz, CDCl3): δ 8.07 (dd, J=8.7, 2.7 Hz, 1H), 7.99 (d, J=2.4 Hz, 1H), 7.72 (d, J=9.0 Hz, 1H), 5.18 (q, J=6.6 Hz, 1H), 2.42, (s, 3H), 1.92-1.88 (br. m, 1H), 1.47 (d, J=6.3 Hz, 3H) ppm.
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