Phosphine-relayed olefination and aza-Wittig reactions of readily available aldehydes with 2,2,2-trifluorodiazoethane （CF3CHN2） have been realized. This protocol enables the facile construction of a series of triflu...Phosphine-relayed olefination and aza-Wittig reactions of readily available aldehydes with 2,2,2-trifluorodiazoethane （CF3CHN2） have been realized. This protocol enables the facile construction of a series of trifluoromethylated alkenes and hydrazones in good to high yield under mild conditions.展开更多
A new approach to the synthesis of co -bromo-dienes was carried out by usingsolid/liquid transferred Wittig reactions between in -bromobutyltriphenylphosphoniumsalt and Q. 6 -unsaturated aldehydes.
Capsaicin and(E)-4-hydroxy-3-methoxybenzyl-8-methylnon-6-enoate were important intermediate of medicine.This research proposed a new method for synthesizing them from 6-bromohexanoic ester by Wittig reaction to give(Z...Capsaicin and(E)-4-hydroxy-3-methoxybenzyl-8-methylnon-6-enoate were important intermediate of medicine.This research proposed a new method for synthesizing them from 6-bromohexanoic ester by Wittig reaction to give(Z)-8-methyl-6-nonenoic acid(4),then treated by nitrous acid and NaNO2 to induce Z→E isomerization reaction of the carbon-carbon double bond,then followed by condensation reaction to give product in an overall yield of 31%.The method is more convenient than traditional methods.展开更多
The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid...The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid (1) in the presence of palladium complexes catalyst. Selective hydroboration and oxidation of 2 by Ca(BH 4) 2/H 2O 2 system gave 8(Z)-heptadecen-1-ol (3), which then was acetylized by treatment with Ac 2O/pyridine to afford 8(Z)-heptadecen-ol acetate(4). The compound 4 was ozonized to form the key intermediate 8-acetoxyoctanal (5), then compound 5 was coupled with the Wittig regents to obtain the title compound 8(Z/E)dodecen-1-ol acetate (6), Z/E molar ratio is 25∶75. The overall yield was 45%. The structures of all the compounds were confirmed by IR, MS and NMR spectra.展开更多
基金This work was supported financially by the National Natural Science Foundation of China （Nos. 21225208, 21472137, and 21532008）, the National Basic Research Program of China （973 Program： Nos. 2014CB745100, 2015CB856500）, and the Tianjin Municipal Science ＆ Technology Commission （No. 14JCQNJC06200）.
文摘Phosphine-relayed olefination and aza-Wittig reactions of readily available aldehydes with 2,2,2-trifluorodiazoethane （CF3CHN2） have been realized. This protocol enables the facile construction of a series of trifluoromethylated alkenes and hydrazones in good to high yield under mild conditions.
文摘A new approach to the synthesis of co -bromo-dienes was carried out by usingsolid/liquid transferred Wittig reactions between in -bromobutyltriphenylphosphoniumsalt and Q. 6 -unsaturated aldehydes.
文摘Capsaicin and(E)-4-hydroxy-3-methoxybenzyl-8-methylnon-6-enoate were important intermediate of medicine.This research proposed a new method for synthesizing them from 6-bromohexanoic ester by Wittig reaction to give(Z)-8-methyl-6-nonenoic acid(4),then treated by nitrous acid and NaNO2 to induce Z→E isomerization reaction of the carbon-carbon double bond,then followed by condensation reaction to give product in an overall yield of 31%.The method is more convenient than traditional methods.
文摘The sex pheromone of grapholitha molesta 8(Z/E)-dodecen-1-ol acetate (6) was synthesized by using oleic acids as the raw material. 1,8(Z)-Heptadecadiene (2) was obtained from the decarbonylation reaction of oleic acid (1) in the presence of palladium complexes catalyst. Selective hydroboration and oxidation of 2 by Ca(BH 4) 2/H 2O 2 system gave 8(Z)-heptadecen-1-ol (3), which then was acetylized by treatment with Ac 2O/pyridine to afford 8(Z)-heptadecen-ol acetate(4). The compound 4 was ozonized to form the key intermediate 8-acetoxyoctanal (5), then compound 5 was coupled with the Wittig regents to obtain the title compound 8(Z/E)dodecen-1-ol acetate (6), Z/E molar ratio is 25∶75. The overall yield was 45%. The structures of all the compounds were confirmed by IR, MS and NMR spectra.
