Cesium carbonate → HCID 59895730, compound

Participants

Reaction Steps

A dry 250 mL three-necked flask was charged with (R)-1-[6-(4-hydroxyphenyl)pyridin-2-yl]-2,2-dimethylpropanol (4b) (2.54 g, 9.9 mmol), cesium carbonate (6.43 g, 19.8 mmol) and 100 mL of acetonitrile. Next, 2-bromoethyl-tert-butyldimethylsilyl ether was added through a dropping funnel. The mixture was heated under reflux for 2 hours and stirred for additional 14 hours at room temperature. After standard work-up with ethyl acetate the crude product was dissolved in 25 mL of THF and 11 mL of TBAF (1 M in THF) were added. After stirring for 1 hour at room temperature, the solution was quenched with 50 mL of water and standard work-up with dichloromethane followed by column chromatography (SiO2, eluent: ethyl acetate/hexanes=1:1) yielded 2.46 g (83%) of (5) as a white powder. Mp: 104° C. [a]D,=−14.4 ©=2.28, acetone). 1H NMR (300 MHZ, CDCl3): δ0.96 (s, 9H); 2.36-2.40 (m, 1H); 3.95-4.01 (m, 2H); 4.11-4.15 (m, 2H); 4.39 (d, J=7.4 Hz, 1H); 4.66 (d, J=7.4 Hz, 1H); 7.01 (d, J=8.8 Hz, 2H); 7.06 (dd, J=7.97 Hz, 0.8 Hz, 1H); 7.57 (dd, J=7.97 Hz, 0.8 Hz, 1H); 7.66 (m, 1H); 7.95 (d, J=8.8 Hz, 2H). 13C NMR (75 MHZ, CDCl3): δ26.0; 36.3; 61.4; 69.4; 80.2; 114.7; 118.2; 120.7; 128.2; 131.9; 136.4; 155.0; 159.3; 159.7. M S 70 eV):m/z(%)301(M, 7),244 (100).IR(KBr): 1608, 1576, 1516, 1453, 1255, 1174, 1046, 812 cm−1. Anal. Calcd. for C18H23NO3: C, 71.73; H, 7.69; N, 4.65. Found: C, 71.59; H, 7.68; N, 4.56.

Provenance & Evidence