The reactions of 1, 3-glycol monotosylates of the configurations A-D with base and LAH were discussed. On reaction with t-butoxide, A and D (cis relationship between-OH and -CH2OTs) gave oxetanes E and F respectively, while B and C (trans relationship between these groups) gave the same seco-aldehyde G. On LAH reduction, in addition to the above reaction (oxetane formation from A and D, seco-alcohol formation from B and C), two further reactions took place ; a) S-O fission (formation of the glycols A-D), and b) C-O fission (formation of the deoxy-compounds H and I), for the latter reaction the cyclic intermediate (K-M) were proposed. The monotosylate of B did not give deoxy-compound. The corresponding keto-tosylate (N and O), when treated with lithium aluminum hydride firstly gave 3β-alcohols (A and C) which are further reduced as above ; the fact which therefore opened a way to yield deoxy-compound (I) from type B glycol (B→N→I).
讨论了构型为 A-D 的 1,3-乙二醇单甲苯磺酸盐与碱和 LAH 的反应。与叔丁醇反应时,A 和 D(OH 和 -CH2OT 之间的顺式关系)分别生成氧杂环丁烷 E 和 F,而 B 和 C(这些基团之间的反式关系)生成相同的仲醛 G。在 LAH 还原过程中,除了上述反应(由 A 和 D 生成氧杂环丁烷,由 B 和 C 生成仲醇)外,还发生了两个反应:a)S-O 裂变(生成乙二醇 A-D);b)C-O 裂变(生成脱氧化合物 H 和 I)。B 的单甲苯磺酸盐没有生成脱氧化合物。相应的酮基对甲苯磺酸盐(N 和 O)用氢化铝锂处理后,首先生成 3β 醇(A 和 C),然后再按上述方法进一步还原;因此,这为从 B 型乙二醇(B→N→I)中生成脱氧化合物(I)开辟了道路。
Triterpenoid chemistry. VI. Iycopodium triterpenoid. (5). The structures and stereochemistry of serratriol, 21-episerratriol, and lycoclavanol.
The structures of triterpenoid-triols, serratriol, 21-episerratriol, and lycoclavanol, isolated from Lycopodium plants, were established as serrat-14-en-3β, 21α, 24-triol (3), serrat-14-en-3β, 21β, 24-triol (36), and serrat-14-en-3α, 21β, 24-triol (22), respectively. The fourth possible stereoisomeric triol, serrat-14-en-3α, 21α, 24-triol (43), was prepared from lycoclavanol. New method of acetonide formation of 1, 3-glycol was reported.