A New Synthesis of Polyquinanes Utilizing alpha-Ketovinylphosphonates

本项目由三个主题组成，如下所述。(1)官能化环戊烷类化合物的简便合成以1-(环戊基-1-烯基羰基)乙烯基膦酸类化合物为原料，成功地合成了一种新的环戊烷环状化合物。1与Lewis酸或多磷酸反应生成2-磷酰环戊烯酮环状化合物，产率为25-71%。(1，3-二氧杂环戊烷-2-基)乙基溴化镁经Michael加成、酸解和分子内Wittig-Horner反应得到二乙烯基酮2(51-70%)。2经纳扎罗夫环合反应生成环戊烷环状化合物3，产率较高。(2)膦酸碳负离子的芳基化反应及与芳基碘在二甲基甲酰胺中的alpha-ArylmethylphosphonatesCopper(I)-catalyzed反应，以较高的产率合成了α-芳基膦酸根。以α-(邻甲酰基苯基)甲基膦酸酯为原料，多聚甲醛、肟或肼为原料，合成了功能化二氢异喹啉N-氧化物和N-苯基(或烷基)亚胺。1，3-偶极与亲偶极体发生1，3-偶极环加成反应生成环加合物。由香茅醛或2，6-二甲基-5-庚烯醛和乙酸三乙酯合成的乙烯基膦酸酯类化合物，以较高的产率得到了立体选择性的含膦基环萜类化合物。双环萜类化合物与多聚甲醛发生Wittig反应，然后进行分子内反应，得到了产率较高到中等的双环萜类化合物。

This project is composed of three subjects as mentioned below. (1) Convenient Synthesis of Functionalized CyclopentanoidsA new approach to cyclopentane annulated compounds was successfully achieved by using 1-(cyclopent-1-enylcarbonyl)vinylphosphonates 1, which we newly developed. Treatment of 1 with Lewis acids or polyphosphoric acid led to 2-phosphorylcyclopentenone annulated compounds in 25-71% yields. The Michael addition of (1,3-dioxolan-2-yl)ethylmagnesium bromide to 1, followed by acidic hydrolysis and the intramolecular Wittig-Horner reaction gave divinyl ketones 2 (51-70%). Nazarov cyclization of 2 produced cyclopentane annulated compounds 3 in good yields. (2) Arylation of Phosphonate Carbanions and Synthetic Application of alpha-ArylmethylphosphonatesCopper(I)-catalyzed reaction of phosphonate carbanions with aryliodides in DMF gave alpha-arylated phosphonates in good yields. Functionalized dihydroisoquinoline N-oxides and N-phenyl(or alkyl) imines were synthesized from alpha-(o-formylphenyl)methyl-phosphonates prepared, paraformaldehyde, and oxime or hydrazines. 1,3-Dipolar cycloaddition of the 1,3-dipoles to dipolarophiles gave the cycloadducts. (3) Synthesis of Cyclic Terpenoids via Intramolecular Ene Reaction of VinylphosphonatesLewis acid promoted intramolecular ene reaction of the vinylphosphonates, prepared from citronellal or 2,6-dimethyl-5-heptenal and triethyl phosphonoacetate, gave stereoselectively cyclic terpenoids bearing the phosphono group in good yields. The wittig reaction of the terpenoids with paraformaldehyde, followed by intramolecular ene reaction provided the bicyclic terpenoids in good to moderate yields.