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To a mixture of 12.9 g (62.5 mmol) of 2-(1-methoxy-2-methyl-2,3-dihydro-1H-inden-4-yl)ethanol and 16.4 g (62.5 mmol) of PPh3 in 300 ml of THF 11.1 g (62.5 mmol) of N-bromosuccinimide was added at vigorous stirring for 5 minutes at 0° C. This mixture was stirred for 2 hours at room temperature and then evaporated to dryness. A solution of the residue in 200 ml of hexanes was filtered through glass frit (G3), and the precipitate was additionally washed by 3×100 ml of hexanes. The combined organic extract was evaporated to dryness. The product was isolated from the residue using flash chromatography on silica gel 60 (40-63 μm, eluent: hexanes-ether=20:1, vol.). Yield 12.1 g (72%) of ca. 1 to 1 mixture of the diastereomers A and B. Anal. calc. for C13H17BrO: C, 58.01; H, 6.37. Found: C, 58.24; H, 6.22. 1H NMR (CDCl3): δ 7.30 (m, 2H, 6-H in indenyl of A and B), 7.20 (m, 2H, 7-H in indenyl of A and B), 7.12 (m, 2H, 5-H in indenyl of A and B), 4.52 (m, 1H, 1-H in indenyl of A), 4.41 (m, 1H, 1-H in indenyl of B), 3.53 (m, 4H, CH2CH2Br of A and B), 3.47 (s, 3H, OMe of B), 3.42 (s, 3H, OMe of A), 3.22 (dd, J=15.8 Hz, J=7.6 Hz, 1H, 3-H in indenyl of B), 3.15 (m, 4H, CH2CH2Br of A and B), 2.92 (dd, J=14.9 Hz, J=6.7 Hz, 1H, 3-H in indenyl of A), 2.48-2.71 (m, 3H, 2,3-H in indenyl of A and 2-H in indenyl of B), 2.42 (dd, J=15.8 Hz, J=4.8 Hz, 1H, 3-H in indenyl of B), 1.18 (d, J=7.1 Hz, 3H, 2-Me in indenyl of B), 1.13 (d, J=6.6 Hz, 3H, 2-Me in indenyl of A). 13C{1H} NMR (CDCl3): δ 143.1, 142.6, 142.2, 141.7, 135.1, 135.0, 128.5, 128.4, 126.8, 126.5, 124.1, 123.8, 91.3, 85.9, 56.7, 56.5, 39.4, 38.5, 36.80, 36.78, 36.7, 36.5, 31.7, 31.6, 19.4, 13.6.

1. additionwas added
2. stirringThis mixture was stirred for 2 hours at room temperature
3. customevaporated to dryness
4. filtrationA solution of the residue in 200 ml of hexanes was filtered through glass frit (G3)
5. washthe precipitate was additionally washed by 3×100 ml of hexanes
6. extractionThe combined organic extract
7. customwas evaporated to dryness
8. customThe product was isolated from the residue
9. additionYield 12.1 g (72%) of ca. 1 to 1 mixture of the diastereomers A and B