萜品油烯的DeMayo光环加成产物的反应研究

通过萜品油烯和2，6-二氧代戊酸甲酯的de Mayo反应，使2 + 2]环加成产物 3-6经retro-aldol重排，开环生成取代环己烯7和12。在不同反应介质中对开环产 物进行再环合，并对其反应机理进行研究。在碱性条件下，经分子内Claisen缩合 反应形成螺环化合物；以对甲本碘酸为催化剂的环合，除生成正常的Claisen缩合 产物以外，7和12均发生烯键亲核加成反应，生成具有二环3.3.1]结构的桥环化合 物9-11和二环3.2.1]结构的桥环化合物16-18。所得新化合物的化学结构均经IR, ~1H NMR，~(13)C NMR及元素分析予以确定。

Study on Reaction of the de Mayo Photocycloaddition Products of Terpinolene

The photocyclo-adducts 36, obtained by photocycloaddition of terpinolene with methyl 2, 3-dioxo-pentanoate, was subjected to retro- aldol rearrangement to give the substituted-cyclohexene 7 and 12. In acidic or basic condition the recyclization of the open-ring products was carried out. In different reaction media the spirocyclic compounds were obtained by intramolecular Claisen condensation. Using TsOH as a catalyst for cyclization the nucleophilic ene-addition of 7 and 12 generated bicyclo 3.3.1] nonene 9～11 and bicyclo 3.2.1] octane 16～ 18 besides forming spirocyclic compounds. The reaction mechanisms were discussed and the structures of all compounds were assigned based on the data from IR, ~1H NMR and ~(13)C NMR and elemental analysis.