6-Iodochroman-4-ol → 6-Iodochroman-4-one
Reaction equation
[I:1][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].C1C=C[NH+]=CC=1.[O-][Cr](Cl)(=O)=O>C(Cl)Cl>[I:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[O:8][CH2:7][CH2:6][C:5]2=[O:12]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a CH2Cl2 (300 ml) suspension of 6-iodo-4-chromanol (15 g, 54.3 mmol) and 30 g of silica gel, at r.t., was added PCC (15.2 g, 70.6 mmol) as a solid. The mixture was stirred at r.t. for 3 h at which time TLC (20% EtOAc/hexanes) indicated complete reaction. The reaction mixture was filtered through a silica gel plug and the filtrate concentrated in vacuo to yield 14.9 g (95%) of 6-iodo-2,3-dihydro-4H-chromen-4-one as a white solid consistent with the literature report (Synthesis 1997, 23–25). HRMS (ESI+) calcd for C9H7IO2 m/z 273.9492; found 273.9500.