[CH3:1][Li].[CH3:3][C:4]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[CH:8][C:5]=1[CH:6]=[O:7]>C(OCC)C.[Ti](Cl)(Cl)(Cl)Cl>[CH3:3][C:4]1[CH:11]=[CH:10][C:9]([N+:12]([O-:14])=[O:13])=[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) (10.0 mL, 17.3 g, 91.0 mmol) and methyl lithium (MeLi) (1.6 M in Et2O, 57.0 mL, 91.0 mmol) in anhydrous diethyl ether (Et2O) (400 mL). A solution of 2-methyl-4-nitro-benzaldehyde (5j) (12.4 g, 75.01 mmol) in anhydrous Et2O (200 mL) was added. Aqueous work-up afforded 13.7 g (99% yield) of the target compound (5k) 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: ˜0.47 (EtOAc/Hxn=1:2 v/v). 1H NMR (300 MHz, CDCl3): δ 8.41 (d, J=2.4 Hz, 1H), 8.00 (dd, J=8.4, 2.4 Hz, 1H), 7.27 (d, J=9.0 Hz, 1H), 5.16 (q, J=6.3 Hz, 1H), 2.43 (s, 3H), 1.96 (br. s, 1H), 1.50 (d, J=6.3 Hz, 3H) ppm. The analytical data correspond to the data of compound (5b) of Method A.
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