| 摘要 |
PURPOSE:To improve the yield of the titled compound useful as a digestion assistant for alkali pulp, with an inexpensive apparatus, by using a silicon dioxide compound as a catalyst of the Diels-Alder reaction of 1,4-naphthoquinone and a conjugated diolefin. CONSTITUTION:The objective compound can be produced by the Diels-Alder reaction of 1,4-naphthoquinone with a conjugated diolefin in the presence of a silicon dioxide compound as a catalyst. The reaction solvent is e.g. benzene, dichloroethane, etc., and the reaction is carried out at 0-25 deg.C, preferably 30-150 deg.C. The conjugated diolefin used in the above reaction is e.g. 1.3-butadiene, isoprene, cyclopentadiene, etc., and its amount is preferably 1.1-10mol per 1 mol of the above raw material. The silicon dioxide compound is e.g. amorphous silica, quartz, tridynite, etc. |
