摘要
通过萜品油烯和 2 ,6 二氧代戊酸甲酯的deMayo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 ;以对甲苯磺酸为催化剂的环合 ,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 ,1HNMR ,13 CNMR及元素分析予以确定 .
The photocyclo-adducts 3 similar to 6, 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-ning 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 similar to 11 and bicyclo [3.2.1] octane 16 similar to 18 besides forming spirocyclic compounds. The reaction mechanisms were discussed and the structures of all compounds were assigned based on the data from IR, H-1 NMR and C-13 NMR and elemental analysis.
出处
《有机化学》
SCIE
CAS
CSCD
北大核心
2003年第10期1120-1124,共5页
Chinese Journal of Organic Chemistry
基金
国家教委留学回国人员科研启动基金 (1 998年度 )资助项目
