反应详情

To a solution of 6-iodochroman-4-ol (1.0 g, 3.6 mmol) in 18 ml of THF, at 0° C., was added the Pd(dppf)Cl2.CH2Cl2 (0.15 g, 0.18 mmol), followed by neopentylmagnesium bromide (10.8 ml, 10.8 mmol, 1.0 M in Et2O). The cold bath was maintained for 10 min., then removed and stirring continued overnight. The mixture was quenched with NH4Cl (30 ml) and extracted with EtOAc (3×50 ml). The combined organic layers were dried over MgSO4 and concentrated in vacuo to yield a brown oil. The crude oil was absorbed onto silica gel followed by flash chromatography (biotage 40S) 10% EtOAc/heptanes to yield 0.36 g (46%) of 6-neopentylchroman-4-ol as a white solid. Rf=0.11. HRMS (ESI+) calcd for C14H20O2 m/z 220.1463 (M+H)+; found 220.1460.

1. temperatureThe cold bath was maintained for 10 min.
2. customremoved
3. customThe mixture was quenched with NH4Cl (30 ml)
4. extractionextracted with EtOAc (3×50 ml)
5. dry with materialThe combined organic layers were dried over MgSO4
6. concentrationconcentrated in vacuo
7. customto yield a brown oil
8. customThe crude oil was absorbed onto silica gel