A Mild and Efficient Bisaldolization
of Ketones and its Application towards Spirocyclic 1,3-Dioxanes
and Novel 1,3,5-Trioxocanes
作者:Kalpana Bhandari、Nagarapu Srinivas、Vijay Marrapu
DOI:10.1055/s-0028-1088130
日期:——
Bisaldolization of aryl alkyl ketones as well as cyclic ketones with paraformaldehyde in the presence of a catalytic amount of l-proline and low concentration of aqueous sodium hydroxide has been developed in excellent yields. Further, these bisaldols are elaborated to the corresponding spirocyclic dioxanes and novel spirocyclic trioxocanes in the presence of p-toluene sulfonic acid. The structures and preferred conformations of these eight-membered spirocyclic 1,3,5-trioxocanes are discussed.
在一定量的 l-脯氨酸和低浓度氢氧化钠水溶液催化下,芳基烷基酮和环酮与多聚甲醛发生双醛化反应,产量极佳。此外,在对甲苯磺酸的存在下,这些双醛醇还可以衍化成相应的螺环二噁烷和新型螺环三氧环。本文讨论了这些八元螺环 1,3,5-三氧杂环的结构和优选构象。