69064-46-6Relevant articles and documents
Synthesis and nuclear magnetic resonance spectroscopic properties of some acetylenic tellura fatty acid esters
Jie, Marcel S. F. Lie Ken,Chau, Sherman H.
, p. 55 - 63 (1997)
Five positional isomers of acetylenic tellura stearate (-5) have been synthesized by three different routes.The number of methylene groups located between the acetylenic system and the tellurium metal varies from 0 to 4.The 1H and 3C NMR spectroscopic properties have been studied.The tellurium atom induces strong deshielding effects on the adjacent methylene protons, which in combination with the deshielding effects of the acetylenic system allows most of the methylene groups between the tellurium and the triple bond to be identified by 1H NMR spectroscopic analysis.The tellurium causes a very strong shielding effects (ca. -27.1 ppm) on the carbon shift of the adjacent α-methylene carbon atom, but weak deshielding effect on the β-(ca. +2.6 ppm) and γ-(ca. +2.3 ppm) methylene carbon atoms.Carbon shifts of methylene carbon atoms, especially those which are located between the tellurium atom and the triple bond, are found very much upfield (δc 0.65-4.81) and in one case in the negative region (δc -17.95) of the 13C NMR spectrum.Most of the signals of the carbon nuclei of these analogue have been identified and from the results of these analyses the number of methylene groups between the acetylenic system and the tellurium atom can be determined. - Keywords: acetylenic, NMR spectroscopy; positional isomers; synthesis; unsaturated tellura; stearate analogues
Synthesis method of gypsy moth sex pheromone
-
Paragraph 0008; 0033-0035, (2020/07/13)
The invention belongs to the technical field of chemical synthesis, and particularly relates to an efficient synthesis method of gypsy moth sex pheromone. According to the synthesis method of gypsy moth sex pheromone, silica gel immobilized ionic liquid is added as a catalyst in the step of asymmetric epoxidation based on an existing synthesis method, so that the Sharpless reaction is effectivelypromoted, the product synthesis rate in the step is increased from 60% to 85%, the synthesis rate of the whole reaction process is further greatly increased, and the synthesis efficiency of the gypsymoth sex pheromone is effectively improved.
Total Syntheses of (R)-Strongylodiols C and D
Liu, Feipeng,Zhong, Jiangchun,Li, Shuoning,Li, Minyan,Wu, Lin,Wang, Qian,Mao, Jianyou,Liu, Shikuo,Zheng, Bing,Wang, Min,Bian, Qinghua
supporting information, p. 244 - 247 (2016/02/05)
The first total syntheses of two marine natural products, (R)-strongylodiols C and D, with 99% ee were achieved. The key steps of the strategy include the zipper reaction of an alkyne, the asymmetric alkynylation of an unsaturated aliphatic aldehyde catalyzed with Trost's ProPhenol ligand, and the Cadiot-Chodkiewicz cross-coupling reaction of a chiral propargylic alcohol with a bromoalkyne.
Catalytic asymmetric synthesis of (S,4E,15Z)-docosa-4,15-dien-1-yn-3-ol, an antitumor marine natural product
Liu, Fei-Peng,Zhong, Jiang-Chun,Zheng, Bing,Li, Shuo-Ning,Gao, Gui,Wang, Zhong-Yu,Li, Min-Yan,Hou, Shi-Cong,Wang, Min,Bian, Qing-Hua
, p. 961 - 965 (2015/09/01)
Abstract An efficient enantioselective total synthesis of an antitumor marine natural product (S,4E,15Z)-docosa-4,15-dien-1-yn-3-ol 1 with 96% ee and 15% overall yield has been achieved; this is the first preparation of 1 via asymmetric catalytic strategy