Intramolecular Etherification and Polyene Cyclization of π-Activated Alcohols Promoted by Hot Water
作者:Feng-Zhi Zhang、Yan Tian、Guo-Xing Li、Jin Qu
DOI:10.1021/jo502636d
日期:2015.1.16
Hot water, acting as a mildly acidic catalyst, efficientlypromoted intramolecular direct nucleophilic substitution reactions of unsaturatedalcohols with heteroatom or carbon nucleophiles. In a mixed solvent of water and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP), polyene cyclizations using allylic alcohols as initiators gave the desired cyclized products, and in neat HFIP, a tricyclization reaction
Acid catalysed rearrangement of a spiroketal enol ether. An easy synthesis of chrycorin
作者:Biao-Lin Yin、Yikang Wu、Yu-Lin Wu
DOI:10.1039/b205229f
日期:2002.7.26
Tonghaosu, 2-[(Z)-hexa-2,4-diynylidene]-1,6-dioxaspiro[4,4]non-3-ene (1a), and its spiroketal enol ether analogues (1b–d and 2) were efficiently converted into interesting cyclopentenone derived oxabicyclic compounds. By applying this reaction protocol the natural product chrycorin was easily synthesized in its racemic form. A reaction mechanism for this is proposed.