Robinson annulation of 2-hydroxymethylene-ketones. A new route to spiro-diketones
作者:V. Dave、J. S. Whitehurst
DOI:10.1039/p19730000393
日期:——
The adducts formed from methyl vinyl ketone and the 2-hydroxymethylene derivatives of cyclic ketones of ring sizes 5, 6, 7, and 1 2 have been cyclised to spiro-ketones containing the same number of carbon atoms. Cyclisation under mild conditions gives ketols, the constitution and stereochemistry of which have been investigated. Methanol containing anhydrous calcium chloride converts the adducts of ring
由甲基乙烯基酮和环大小为5、6、7和1 2的环状酮的2-羟基亚甲基衍生物形成的加合物已被环化为含相同碳原子数的螺酮。在温和条件下环化可得到酮醇,已经研究了酮醇的组成和立体化学。含有无水氯化钙的甲醇将环大小为7和1 2的加合物转化为螺醚。C 6加合物给出了不同构成的产物。螺酮都在大约有uv吸收带。224 nm(μ约6500),但第二个大约相同强度的谱带出现在246 nm的环形尺寸5和12。