摘要 |
The present invention relates to a method of preparing chromanes from 2,5-dimethylfuran and substituted alkynes comprising an long chain unsaturated alkyl group as substituent in the alpha position of a substituted phenol followed by oxidation, reduction and acid ring closure. It is particularly advantageous to use 2,5-dimethylfuran as this offers an ecological beneficial synthesis of β-tocopherol. |