Synthesis of Bornene Ring-fused Dihydrothiopyrans, a New Class of Chiral Cyclic Sulfides, via Intramolecular Hetero Diels-Alder Reaction of Homochiral Thiabutadienes, 3-(Arylmethylene)thiocamphors
摘要:
A highly diastereoisoface-selective intramolecular hetero Diels-Alder reaction of homochiral camphor-derived thiabutadienes to afford novel, optically active bornenee ring-fused dihydrothiopyrans is described for the first time.
The possibilities of synthesizing various α-trifluoromethylated oxygenated heterocycles, starting from trifluoroacetaldehyde methyl hemiacetal, through classic cyclization reactions, have been demonstrated. In this way, six-membered cyclic compounds, δ-lactones and also macrolactones, bearing a CF3 group in a position α to the oxygen could be easily obtained through a RCM reaction. Bicyclic compounds could be also synthesized by an intramolecular Pauson-Khand reaction.
transformation of a wide variety of alcohols or carboxylic acids into the corresponding halides. Yields are high and conditions are very mild thus allowing for the presence of sensitive functional groups. The reagents can be easily tuned allowing therefore the selective monohalogenation of polyhydroxylated molecules. The scope and chemoselectivity of the reactions have been studied and reaction mechanisms
Total Synthesis of (±)-Spiniferin-1 via a Polyfluoroalkanosulfonyl Fluoride Induced Homoallylic Carbocation Rearrangement Reaction
作者:Kai Ding、Yun-shan Sun、Wei-Sheng Tian
DOI:10.1021/jo102351k
日期:2011.3.4
A facile total synthesis of marine natural product (±)-spiniferin-1 has been accomplished in eight steps with 28.9% overall yield, involving a rearrangement reaction initiated by polyfluoroalkanosulfonyl fluoride to construct the 1,6-methano[10]annulene core of the natural product as a key step.