Hexane → (4R)-4-[(1R,7aR)-octahydro-4-trimethylsilyloxy-7a-methyl-1H-inden-1-yl]-pentanal

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A 3.79 g amount of the compound (4-6), methyl(4R)-4-[(1R,7aR)-octahydro-4-trimethylsilyloxy-7a-methyl-1H-inden-1-yl]-heptanoate was taken in a 300 ml eggplant-shaped flask, 100 ml of hexane was added, and the solution was stirred and cooled to −95° C. Thereafter 12.3 ml of a hexane solution (0.93 mol/liter) of diisobutylaluminum hydride was added and the solution stirred for 1 hour. A 100 ml amount of methanol was used to break down the excess reducing agent, then 30 ml of a saturated aqueous solution of ammonia chloride and 50 ml of ether were added and the solution was stirred at room temperature for 1 hour. The insolubles were removed by filtration by Celite, then the solution was separated and the aqueous layer was extracted by ether. The organic layer was washed two times by saturated saline in an amount of 50 ml, then was dried over anhydrous magnesium sulfate. The desiccant was filtered out, then the solvent was distilled off under reduced pressure to obtain a crude product in an amount of 4.07 g. This was purified by a silica gel column (Merck gel: 300 g, hexane/ethyl acetate=50/1) to obtain the desired product (4-7), (4R)-4-[(1R,7aR)-octahydro-4-trimethylsilyloxy-7a-methyl-1H-inden-1-yl]-pentanal in an amount of 3.17 g (yield 92%).

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