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].[Cl-].[CH2:14]([Zn+])[C:15]([CH3:18])([CH3:17])[CH3:16]>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]>[CH2:14]([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:15]([CH3:18])([CH3:17])[CH3:16]To a flame dried round bottom flask containing 6-iodo-chroman-4-ol (3.0 g, 10.8 mmol) and Pd(dppf)Cl2 (0.44 g, 0.54 mmol) was added 6 ml of anhydrous THF and the mixture chilled to 0° C. The mixture was treated with neopentyl zinc chloride (prepared as previously described) (50 ml, 30 mmol, 0.6 M in THF) and stirred under nitrogen at r.t. for 19 h. followed by 5 h at 50° C. (oil bath). The reaction was cooled to r.t. and quenched with NH4Cl and extracted with EtOAc. The organic layer was dried over Na2SO4 and concentrated in vacuo to 1.9 g (79%) of a white solid after flash chromatography (10% EtOAc/heptanes, Biotage 40M) Rf=0.11. HRMS (ESI+) calcd for C14H20O2 m/z 220.1463 (M+H)+; found 220.1460.
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