Stereospecificannulation of hydroxyvinylethers in the presence of triflic anhydride and tertiary amines and its syntheticapplication are described. Each 1-hydroxy-2-oxabicyclo[n.4.0]alkane, 2-oxabicyclo[n.4.0]alk-1(6)-ene and 2-oxabicyclo[n.4.0]alk-1(6+n)-ene is stereoselectively synthesized from the same hydroxyvinylether depending on the choice of the reaction conditions (temperature, solvent
描述了在三氟甲磺酸酐和叔胺存在下的羟基乙烯基醚的立体定向环氧化及其合成应用。每个1-羟基-2-氧杂双环[n.4.0]烷烃,2-氧杂双环[n.4.0] alk-1(6)-烯和2-氧杂双环[n.4.0] alk-1(6 + n)-烯根据反应条件(温度,溶剂和叔胺)的选择,由相同的羟基乙烯基醚立体选择性地合成。这些化合物导致多官能化的环状化合物和一些天然产物。我们提出,这种环化反应是通过纯S N 2样机理进行的。
Process for the preparation of 1-hydroperoxy-16-oxabicyclo[10.4.0]hexadecane
申请人:Lambrecht Stefan
公开号:US20050085536A1
公开(公告)日:2005-04-21
Process for the preparation of 1-hydroperoxy-16-oxabicyclo[10.4.0]hexadecane (DDP-OOH), wherein 13-oxabicyclo[10.4.0]hexadec-1(12)-ene (DDP) and hydrogen peroxide are reacted in a diluent in the presence of a strong acid, the diluent has a pKa value of greater than or equal to 4.5 and the strong acid has a pKa value of less than or equal to 1.5, wherein after the reaction has taken place, the strong acid is neutralized with at least 0.9 molar equivalent of a base.
The present invention relates to novel macrocyclic lactones, to processes for their preparation and to their use as fragrances and also to products comprising the novel macrocyclic lactones.
Highly regio- and stereo-selective annulationâelimination reactions of 1-cycloalkenyl 3-hydroxypropyl ethers in the presence of triflic anhydride and tertiary amines are described; the bicyclic vinyl ethers produced are converted to 2-substituted δ-lactones, macrocyclic oxolactones and bicyclic hydroxy ethers by ozonolysis and stereoselective hydroboration.