Diethyl Ether → (1s,2s)-2-(4-Chlorophenoxy)-1,2,-dihydro-naphthalen-1-ol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a flame dried round-bottomed flask, [Rh(COD)Cl]2 (1.7 mg, 0.0035 mmol), (S)—(R)-PPF-PtBu2 (3.8 mg, 0.0069 mmol) and 1 (100 mg, 0.694 mmol) were added followed by addition of THF (2.5 mL) and 4-chlorophenol (446 mg, 3.47 mmol). The mixture was heated at 80° C. for 6 hours, then poured into diethyl ether and extracted 3 times with 10% aqueous sodium hydroxide solution. The aqueous extracts were combined and back-extracted three times with diethyl ether. The combined ether extracts were washed with brine and dried with anhydrous sodium sulfate. The solvents were removed in vactio, yielding a solid which was purified by flash chromatography on silica gel (5% ethyl acetate in hexanes) giving a white crystalline solid 8 (169 mg, 89%). The ee was determined to be 92% by formation of Mosher's ester. Rf=0.47 on silica (20% ethyl acetate in hexanes); mp 125-125.5° C. (Et2O); [α]25D=+150° (c=10.6, CHCl3). IR (KBr, cm−1) 3302 (br), 3064 (w), 2874 (w), 1590 (m), 1489 (s), 1362 (w), 1230 (s), 1052 (m), 890 (w), 846 (m), 778 (s), 663 (m); 1H NMR (400 MHz, CDCl3): δ 7.65-7.64 (1H, m), 7.33-7.26 (4H, m), 7.16-7.13 (1H, m), 6.91(1H, ddd, J=2.0, 2.0, 8.9 Hz), 6.55 (1H, dd, J=1.8, 9.9 Hz), 5.99 (1H, dd, J=2.2, 9.9 Hz), 5.19 (1H, dd, J=3.8, 10.0 Hz), 5.07 (1H, ddd, J=2.0, 2.0, 10.1 Hz), 2.56 (1H, d, J=4.0 Hz);

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