Rearrangement Approaches to Cyclic Skeletons. IV. The Total Synthesis of (±)-Pinguisone and (±)-Deoxopinguisone Based on Photochemical [1,3] Acyl Migration of a Bicyclo[3.2.2]non-6-en-2-one
作者:Tadao Uyehara、Yasuhiro Kabasawa、Tadahiro Kato
DOI:10.1246/bcsj.59.2521
日期:1986.8
2-chloroacrylonitrile. Ring enlargement of 9 using (CH3)3SiCHN2 and BF3 etherate gave the corresponding bicyclo[3.2.2]oct-6-en-2-one (8). The photochemical [1,3] acyl migration of 8 gave the [5–6] fused-ring compound (7). The fourth methyl was introduced selectively by the conjugate addition of (CH3)2CuLi to the spiro[bicyclo[4.3.0]non-8-ene-3,2′-[1,3]dioxolan]-7-one prepared from 7. Each furan ring of 2 and 3 was
(±)-Pinguisone (2) 和 (±)-deoxopinguisone (3), [5–6] 稠环倍半萜烯的全合成已经从 1-甲氧基-3,4,5-三甲苯开始实现。1-Methoxy-4,5,endo-8-trimethylbicyclo[2.2.2]non-5-en-2-one (9) 是通过苯衍生的二烯和 2-氯丙烯腈。使用 (CH3)3SiCHN2 和 BF3 醚合物对 9 进行扩环得到相应的双环 [3.2.2]oct-6-en-2-one (8)。8 的光化学 [1,3] 酰基迁移得到 [5-6] 稠环化合物 (7)。通过将 (CH3)2CuLi 共轭加成到由 7 制备的螺[双环 [4.3.0]non-8-ene-3,2'-[1,3]dioxolan]-7-one 中选择性地引入第四个甲基.