Phenol → 4,4-Dimethylchroman
Reaction equation
[C:1]1([OH:7])[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.P([O-])([O-])(O[CH2:11][C:12](C1C=CC=CC=1)([C:16]1C=CC=CC=1)[C:13](C)=[CH2:14])=O>C(=S)=S>[CH3:11][C:12]1([CH3:16])[C:6]2[C:1](=[CH:2][CH:3]=[CH:4][CH:5]=2)[O:7][CH2:14][CH2:13]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
To a dry, ice-cooled flask containing 34.95 g (0.134 mol) of stannic chloride was added quickly under argon 63.0 g (0.669 mol) of phenol. The mixture was stirred at 0 degrees C for 0.5 hour and then treated with 43.0 g (0.135 mol) of diphenyl-3-methyl-3-buten-1-yl phosphate (Compound 75), followed by a 5 ml carbon disulfide rinse. The mixture was stirred at room temperature for 21 hours and then quenched by pouring onto 700 g ice and 1 liter of 1.5N NaOH. The mixture was extracted with 1×600 ml and 2×300 ml ether. The combined ether fractions were washed with 2N NaOH, saturated NaCl and dried (MgSO4). Solvent was removed in vacuo and the residue purified by flash chromatography (silica; 2% ether in hexane) to give the title compound as a colorless oil. PMR (CDCl3) &: 1.34 (6H), 1.80-1.85 (2H, m), 4.15-4.20 (2H, m), 6.80 (1H, dd, J~8.1 hz, 1.5 Hz), 6.87 (1H, td, J~8.1 Hz, 1.5 Hz), 7.07 (1H, td, J~8.1 Hz, 1.5 Hz), 7.26 (1H, dd, J~8.1 Hz, 1.5 H).