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1.
林国强  曾春民 《化学学报》1993,51(2):197-201
本文报道合成美洲白蛾性信息素(3Z-6Z)-9S, 10R-环氧-二十一碳双烯(1)的路线。从双乙烯甲醇出发, 经过十步合成到1, 总得率为16.85。  相似文献   

2.
11-Tetradecen-1-ol acetate is a mixture of geometric isomers with the Z/E-conformations in a 94:6 ratio that is used as an attractant to trap corn pests. It has a powerful attractive action similar to that of an isomeric mixture of 11-tetradecenyl acetate with the Z/E-conformation in a 95:5 ratio that was extracted from the peritoneal cavity of male Ostrinia nubilalis Hubner in Xinjing (PRC). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 177–178, March–April, 2008.  相似文献   

3.
《Tetrahedron letters》1987,28(26):2977-2978
A ten-step synthesis of the title pheromone and its (3Z,6E)-stereoisomer from an acyclic derivative of D-xylose is described.  相似文献   

4.
Syntheses of (4E,6E,11Z)-4,6,11-hexadecatrienyl acetate (1) and (4E,6E, 11Z)-4, 6,11-hexadecatrienal (2), female sex pheromones of eri-silkworm,Samia cynthia ricini have been achieved through Claisen ortho ester rearrangement of (6).  相似文献   

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Stereoselective syntheses on a gram scale of (3Z,6E,8E)-, (3Z,6E,8Z)-and (3Z,6Z,8Z)-3,6,8-dodecatrien-1-ol, 8, 9 and 10, respectively, are described. A key step of the synthesis of 8 consisted of a copper-mediated coupling reaction between 4-(2-tetrahydropyranyloxy)-1-butynylmagnesium bromide (15) and the mesyl ester of (2E,4E)-2,4-octadien-1-ol (14). A similar copper-mediated reaction between 15 and the mesyl ester of (E)-2-octen-4-yn-1-ol (19) was used to construct the C-12 carbon skeleton of 9. On the other hand, the synthesis of 10 was based on a palladium-promoted reaction between (Z)-1-bromo-1-pentene (23) and the organozinc bromide derived from 3,6-heptadiyn-1-yl acetate (27).  相似文献   

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(Z,Z)-6,9-Nonadecadien-3-one and (Z,Z,Z)-3,6,9-nonadecatriene were identified by GC-EAD and GC-MS in ovipositor extracts of P. rhomboidaria; the synthetic mixture is attractive to males of the species in the field.  相似文献   

10.
Pure (7E,9Z-7, 9-dodecadien-1-yl acetate (1), the sex pheromone of Lobesiabotrana, has been prepared in 21.6% overall yield by a reaction scheme involving; (i) the cross-coupling of (E) - 8 - (2 - tetrahydropyranyloxy) -1 - octenyldisiamylborane with 1 - bromo - 1 - butyne, in the presence of a Pd (O) catalyst and base; (ii) the acetylation of the crude product of this reaction; (iii) the (Z)-stereoselective reduction of the obtained conjugated (E)-enyn-1-yl acetate. (E)-9,11-Dodecadien-1-yl acetate (2), a sex pheromone component of Diparopsiscastanea, has been analogously obtained (in 54.3% overall yield) by cross-coupling of (E) - 10 - (2 - tetrahydropyranyloxy) - 1 - decenyl borane with vinyl bromide, in the presence of a Pd (O) catalyst and base, followed by acetylation of the crude product. Compound 2, which was 87.7% chemically pure, was purified by column chromatography over SiO2-AgNO3. Chemically pure (9Z, 11E) - 9,11 - tetradecadien - 1 - yl acetate (3), a sex pheromone component of Spodopteralittoralis, has been prepared (in 30.2% overall yield) by reaction of 10 - (2 - tetrahydropyranyloxy) - 1 - decynylamagnesium bromide with (E)-1-iodo-1-butene, in the presence of a Pd (O) catalyst, followed by acetylation of the crude product and by (Z)-stereoselective reduction of the obtained (E)-enyn-1-yl acetate.The stereoisomeric purity of 1, 2 and 3 has been evaluated by glc analysis on glass capillary columns or by reverse phase hplc analysis.  相似文献   

11.
(3Z,9Z,6S,7R)-6,7-epoxy-3,9-octadecadiene (1) and (3Z,9Z,6R,7S)-6,7-epoxy-3,9-octadecadiene (2) have been stereoselectively synthesized in eight steps from 2-pentyn-1-ol with an overall yield of 8%. The key steps involved the Sharpless asymmetric dihydroxylation of (2E)-oct-2-en-5-yn-1-ol (6). The new synthetic method is suitable for multigram-scale preparation of 1 and 2 and might be used for producing sufficient quantities of the sex pheromone components for management of the pest of tea plantations.  相似文献   

12.
Starting from the aldehydes 2 and 9 the acetylene 16 is prepared via the borane 15 by means of a combined Wittig reaction-hydroboration reaction sequence. 16 may be converted into the (E)-6,(Z)-11-hexadecadienylacetate (18) and the corresponding aldehyde 19. The synthetic route proceeds with high stereospecifity (isomeric purity of 18 and 19 ? 97%).  相似文献   

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Components of the Grapholitha molesta sex pheromone, (Z/E)-8-dodecenyl acetates (1, 2), were synthesized in five steps in 20% overall yield using 10-hydroxydecanoic acid (3) as starting material. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 592–594, November–December, 2006.  相似文献   

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Summary.  Ab initio calculations at the HF/6-31G* level of theory for geometry optimization and the MP2/6-31G*//HF/6-31G* level for a single point total energy calculation are reported for (Z,Z)-, (E,Z)-, and (E,E)-cycloocta-1,4-dienes. The C 2-symmetric twist-boat conformation of (Z,Z)-cycloocta-1,4-diene was calculated to be by 3.6 kJ·mol−1 more stable than the C S-symmetric boat-chair form; the calculated energy barrier for ring inversion of the twist-boat conformation via the C S-symmetric boat-boat geometry is 19.1 kJ·mol−1. Interconversion between twist-boat and boat-chair conformations takes place via a half-chair (C 1) transition state which is 43.5 kJ·mol−1 above the twist-boat form. The unsymmetrical twist-boat-chair conformation of (E,Z)-cycloocta-1,4-diene was calculated to be by 18.7 kJ·mol−1 more stable than the unsymmetrical boat-chair form. The calculated energy barrier for the interconversion of twist-boat-chair and boat-chair is 69.5 kJ·mol−1, whereas the barrier for swiveling of the trans-double bond through the bridge is 172.6 kJ·mol−1. The C S symmetric crown conformation of the parallel family of (E,E)-cycloocta-1,4-diene was calculated to be by 16.5 kJ·mol−1 more stable than the C S-symmetric boat-chair form. Interconversion of crown and boat-chair takes place via a chair (C S) transition state which is 37.2 kJ·mol−1 above the crown conformation. The axial- symmetrical twist geometry of the crossed family of (E,E)-cycloocta-1,4-diene is 5.9 kJ·mol−1 less stable than the crown conformation. Corresponding author. E-mail: isayavar@yahoo.com Received March 25, 2002; accepted April 3, 2002  相似文献   

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A simple method for synthesizing (11E, 13E)-11, 13-hexadecadienal 7, a component of the female sex pheromone of cabbage webworm, and its geometrical isomer (11Z, 13E)-11, 13-hexadecadienal 8 is described.  相似文献   

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