References
- Bonini , C. and Righi , G. 1994 . Regio- and chemoselective synthesis of halohydrins by cleavage of oxiranes with metal halides . Synthesis , : 225 – 238 . and references cited therein
- Boyd , V.A. , Najjar , Y.P. , Ytuarte , L.A. , Savage , M.R. , Perales , J.B. and Negrete , G.R. 1998 . Complementary approaches to the preparations of cis and trans aminohydrins . Tetrahedron Lett. , 39 : 3459 – 3462 .
- Bajwa , J.S. and Anderson , R.C. 1991 . A highly regioselective conversion of epoxides to halohydrins by lithium halides . Tetrahedron Lett. , 32 : 3021 – 3024 .
- Each of the chlorohydrins exhibited a consistent pattern of signals (around 4.8–5.8 ppm range) for the diastereotopic protons on the chlorinated carbon with an upfield signal displaying a larger coupling constant (4–6 Hz) compared to the downfield signal (1–2 Hz)
- (±)-Trans-7-Chloro-8-hydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene: R f = 0.34 (4:1 hexane/EtOAc). The compound exhibited 1H NMR identical to that previously reported (3). Additional spin–spin splitting data and 13C NMR are presented here: 1H NMR (300 MHz CDCl3): δ 2.17 (ddt, J = 6.6, 13.6, 8.4 Hz, 1H, H9), 2.65 (ddt, J = 3.3, 13.6, 6.2 Hz, 1H, H9′), 3.54 (ddd, J = 17.6, 7.7, 7.0 Hz, 1H, H10), 3.66 (dt, J = 17.6, 6.2 Hz, 1H, H10′), 4.39 (ddd, J = 3.3, 6.5, 8.8 Hz, 1H, H8), 5.48 (d, J = 6.6 Hz, 1H, H7), 7.96–8.03 (m, 3H), 8.11–8.23 (m, 4H), 8.33 (s, 1H); 13C NMR: δ 23.5 (t), 27.3 (t), 65.0 (d), 72.3 (d), 122.8 (d), 124.5 (s), 125.2 (d), 125.3 (d), 126.2 (d), 126.6 (d), 127.2 (d), 127.3 (d), 127.9 (d), 128.5 (s), 129.6 (s), 130.1 (s), 130.9 (s), 131.5 (s), 131.7 (s)
- Typical procedure for the hydrochlorination of 7,8-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (EBP): To a solution of EBP (270 mg, 1 mmol, 0.01 M) in the indicated solvent, lithium chloride (423 mg, 10 mmol) and potassium hydrogen phthalate (204 mg, 1 mmol) were added. The reaction mixture was stirred at room temperature under nitrogen atmosphere until the completion of the reaction was indicated by TLC. The reaction mixture was filtered and solvent was evaporated under reduced pressure. The residue was then dissolved in CH2Cl2 (25 mL) and washed with sat. NaHCO3 solution (twice, 10 mL each) and then with brine solution (twice, 10 mL each). The organic layer was dried over anhydrous Na2SO4 and the solvent was removed under reduced pressure. The solid residue was chromatographed (4:1 hexane:EtOAc) to yield highly enriched cis and trans diastereomers
- (±)-cis-7-Chloro-8-hydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene: R f = 0.26 (4:1 hexane/EtOAc). 1H NMR: δ 2.24–2.35 (m, 1H, H9), 2.38–2.53 (m, 1H, H9′), 3.43 (ddd, J = 7.0, 10.8, 17.8 Hz, 1H, H10), 3.81 (ddd, J = 2.9, 6.2, 17.9 Hz, 1H, H10′), 4.37 (ddt, J = 11.4, 9.7, 3.5 Hz, 1H, H8), 5.79 (d, J = 3.3 Hz, 1H, H7), 7.97–8.03 (m, 3H), 8.10–8.21 (m, 5H); 13C NMR: δ 25.4 (t), 26.5 (t), 66.5 (d), 69.0 (d), 122.8 (d), 124.9 (s), 125.3 (d), 126.3 (d), 126.9 (d), 127.2 (d), 127.3 (d), 128.0 (d), 128.8 (s), 129.1 (s), 130.1 (s), 131.0 (s), 131.5 (s), 132.4 (s)
- Dolenc , D. and Harej , M. 2002 . Direct conversion of bromohydrins to ketones by a free radical elimination of hydrogen bromide . J. Org. Chem. , 67 : 312 – 313 .
- Piva , O. 1992 . Direct conversion of bromohydrins to ketones . Tetrahedron Lett. , 33 : 2459 – 2460 .
- Bellucci , G. , Berti , G. , Macchia , B. and Macchia , F. 1973 . Stereoselectivity and regioselectivity in the ring opening of 1-(p-nitrophenyl)-1,2-epoxycyclohexane with hydrogen halides. unusually marked dependence on solvent and type of acid . Gazz. Chim. Ital. , 103 : 345 – 354 .
- Bartas-Yacoubou , J.-M. , Maduike , N. , Kyere , S. , Doan , L. and Whalen , D.L. 2002 . Aryl epoxide-halohydrin transformations: stereochemistry of reactions of aryl epoxides with lithium halide-acetic acid reagent . Tetrahedron Lett. , 43 : 3781 – 3782 .