Isopropyl methanesulfonate → 3-Isopropyl-5,5',6,6',7,7',8,8'-octahydro-2,2'-binaphthol

Beteiligte Stoffe

Reaktionsschritte

A mixture of 5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-binaphthol (2 g, 6.8 mmol), isopropyl methanesulfonate (5.5 mmol), scandium triflate (0.34 g, 5 mol %), and carbon tetrachloride (10 ml) was brought to reflux under argon. After 18 hours, GC indicated 65% conversion to give 78% desired product. Additional isopropyl methanesulfonate (3.1 mmol) was added, and the reaction mixture was refluxed for another 8 hours. GC showed 86% conversion, and 76% selectivity to 3-isopropyl-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-binaphthol. The mixture was diluted with ether (20 ml) and 10% HCl (20 ml). The layers were separated, and the aqueous layer was extracted with ether (3×20 ml). The ether layers were combined, dried (MgSO4), and concentrated. The crude product was purified by column chromatography (SiO2, 2% ethyl acetate/hexanes) to yield 1.1 g white solid (48%). MP: 100–102° C.

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