I[C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH2:7][CH2:6][CH:5]2[OH:12].C(Cl)Cl.[CH2:16]([Mg]Br)[C:17]([CH3:20])([CH3:19])[CH3:18]>C1COCC1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2]>[CH2:16]([C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH2:7][CH2:6][CH:5]2[OH:12])[C:17]([CH3:20])([CH3:19])[CH3:18]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.
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