| 摘要 |
NEW MATERIAL:A compound expressed by formula I (R1 and R2 are 1-20C alkyl and two alkoxy OR1 and OR2 show cis structure to the face of tetrahydrofuran ring). EXAMPLE:(R,S)-3,4-Dimethoxytetrahydrofuran. USE:The compound expressed by formula I exhibits extremely high dielectric constant and is used for a solvent or non-protonic polar solvent for e.g. condenser or electric cell or raw material for organic fine chemicals, etc. PREPARATION:A mixed liquid of erythritol expressed by formula II, water and concentrated sulfuric acid are heated while refluxing in order to subject the mixed liquid to dehydrocyclization to give (R,S)-2,3-dihydroxytetrahydrofuran expressed by formula III (two OH show cis structure to the face of tetrahydroxy furan ring) which is then reacted with an alkali metal compound such as NaH to afford the corresponding alkali metal salt, which is further reacted with 1-20C alkylating agent such as dimethylsulfuric acid in an inert solvent to provide the compound expressed by formula I. |
