[CH:1]1[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.[Cl-].[Cl-].[Cl-].[Al+3].[C:11](Cl)(=[O:16])/[C:12](=[CH:14]/[CH3:15])/[CH3:13]>Cl>[CH3:13][CH:12]1[CH:14]([CH3:15])[C:6]2[C:1](=[CH:2][CH:3]=[CH:4][CH:5]=2)[C:11]1=[O:16]Under an argon atmosphere benzene (335 ml, 3.74 mol) and aluminum trichloride (90.78 g, 0.68 mol) were introduced into a 1 liter three necked round bottomed flask fitted with a magnetic stirring apparatus, an addition funnel and a reflux condenser. The stirred orange mixture was cooled to 7° C. and tigloyl chloride (33) (40 g, 0.34 mol) was added dropwise via an addition funnel. After completion of the addition, the mixture was allowed to come to room temperature and then refluxed overnight. Then the reaction mixture was allowed to come to room temperature and poured onto mixture of ice (300 g) and conc. HCl (50 ml). The organic layer was separated and washed with a saturated solution of sodium bicarbonate (3×100 ml), then dried over magnesium sulfate and filtered. The excess benzene was removed under reduced pressure to afford (34) (50.02 g, 92%) as a yellow liquid. The 1H NMR spectrum was identical with the literature (T. E. Ready, J. C. W. Chien, M. D. Rausch, J. Org. Chem. 1999 583, 11-27; J. Sarrazin, A. Tallec, Tetrahedron Letters, 1977, 18, 1579-1582; M. Hiscock, G. B. Porter, J. Chem. Soc. (B), 1971, 1631-1634). 1H NMR (200 MHz, CDCl3): δ [ppm] 7.76-7.34 (m, 4H, arom), 2.94 (dq, 3J=4.9 Hz, 3J=7.0 Hz, 1H, H-position 2), 2.24 (dq, 3J=7.3 Hz, 3J=4.7 Hz, 1H, H-position 3), 1.46 (d, 3J=6.9 Hz, 3H, CH3-position 2), 1.32 (d, 3J=7.3 Hz, 3H, CH3-position 3).
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