References
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- Yamaguchi , M. 1956 . Nippon Kagaku Zasshi , 77 : 591 Only simple benzaldehydes were reported to give the corresponding acid halides in poor to moderate yields by this type of reaction. Chem. Abstr. 52, 305e (1958)
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- Result of our experiment according to Nohara et al.,4
- 6-Ethyl group was also susceptible to benzylic oxidation: Treatment of 1, (X=6-Et) with 1.2 mol equiv NBS (hp, CC14) followed by aqueous workup gave a mixture consisting mainly of 1, (X=6-CHBrMe) (NMR (CDCl3) < 2.06 (d, J=7Hz), 5.25 (q,J=7Hz), 7.52 (d,J=8Hz), 7.86 (dd,J=8Hz,2Hz), 8.26(d,J=2Hz), 8.53 (s), 10.36 (s); MS m/e 280, 282 (M+)) and 2, (X'=6-CHBrMe, Y=OH) (NMR (CDCl3) δ 2.06 (d,J=7Hz), 5.25 (q,J=7Hz), 7.61 (d,J=8Hz), 7.96 (dd,J=8Hz,2Hz), 8.34 (d,J=2Hz), 9.00 (s); MS m/e 252, 254 (M-CO2)) in a ratio of ca. 3:1. A similar reaction using 3 mol equiv NBS afforded a mixture consisting mainly of 2, (X'=6-CBr2Me, Y=OH) (NMR (Me2SO-d6) δ 2.58 (s), 7.8–8.8 (m), 9.05 (s); MS m/e 374, 376, 378 (M+)). Attempted isolation of the products in pure form failed