35857-62-6Relevant articles and documents
Close-range attraction in Lygocoris pabulinus (L.)
Drijfhout, Falko P.,Groot, Astrid T.
, p. 1133 - 1149 (2007/10/03)
Males of the green capsid bug, Lygocoris pabulinus, exhibit a specific courtship behavior, i.e., a vibration of the abdomen. When both live and dead females were offered to males, this vibration behavior was elicited in most of the males tested. When females were dissected into separate body parts, heads, wings, and legs elicited equal responses, while thorax plus abdomen elicited a much lower response. When separate body parts were extracted, the leg extracts elicited significantly stronger responses than any other extract. This suggests that female L. pabulinus legs are either the source of a close-range sex pheromone or that pheromone is accumulated on the legs due to grooming behavior. The leg extracts contained several hydrocarbons such as n-alkenes, n-alkanes, and some methylalkanes. Female extracts contained more (Z)-9-pentacosene and male extracts contained more (Z)-9-heptacosene. Substrates on which females had walked elicited similar responses as female legs, indicating that the pheromone is deposited on the substrate. This enlarges the functional range of low-volatility compounds, which are thought to function only when sexes are in close vicinity or in contact.
The synthesis of long chain dialkylalkynes, dialkyldiynes and their hydrogenation to monoenes and dienes
Fisher,Tyman
, p. 1323 - 1338 (2007/10/03)
Long methylenic chain dialkylalkynes have been synthesised in high yield by an improved procedure. The methodology has been extended to nonconjugated diynes. Catalytic hydrogenation with a poisoned palladium catalyst affords cis-monoenes and cis, cis-dienes respectively. An improved synthesis of cis- 9-tricosene is described.
Opposite stereochemical effects exerted by CeCl3 and TiCl4 on the Lewis acid mediated reduction of α-alkyl-β-ketophosphine oxides with metallic hydrides: A highly stereoselective protocol for the synthesis of syn and anti α-alkyl-β-hydroxyphosphine oxides
Bartoli, Giuseppe,Bosco, Marcella,Dalpozzo, Renato,Marcantoni, Enrico,Sambri, Letizia
, p. 1941 - 1950 (2007/10/03)
A general, highly efficient methodology for obtaining both syn and anti α-hydroxyphosphine oxides by reduction of the corresponding α-ketophosphine oxides is described. The nature of the Lewis acid was found to be pivotal in determining the outcome of these reactions. Strongly chelating TiCl4 led to the anti isomer in high diastereoisomeric excess in noncoordinating solvents (CH2Cl2) at -78°C with BH3/py as reducing agent, while nonchelating CeCl3 gave a high excess of the syn isomer in coordinating solvents (THF) at the same temperature with LiBH4 as reducing agent. In the latter case, CeCl3 is essential in achieving high yields and stereoselectivity, since it allows the reaction to be performed at low temperatures. Otherwise, higher temperatures (0 °C) are required, which lower both yields and selectivities. Moreover, each step of the protocol for the synthesis of stereodefined disubstituted olefins from alkylphosphine oxides (Warren's modification of the Homer procedure) has been optimized, and the optimized procedure has been applied to the synthesis of muscalure, the pheromone of the domestic fly.
ENAMINE CONDENSATION ON DERIVATIVES OF ALEURITIC ACID AND SYNTHESIS OF (Z)-9-TRICOSENE (MUSCALURE), ITS (E)-ISOMER, AND (E)-13-HEPTACOSENE
Subramanian, G. B. V.,Mehrotra, Alka,Mehrota, Kalpana
, p. 3967 - 3972 (2007/10/02)
Enamine condensation on (9RS,10RS)-9,10,16-triacetoxy hexadecanoyl chloride as well as (7RS,8RS)-7,8-diacetoxypentadeca-1,15-dioyl chloride using 1-morpholino-1-cyclohexene led to chain elongated products with 22 and 27 carbon atoms and its (E)-isomer while the latter led to a synthesis of (E)-13-heptacosene.
A General Approach to the Synthesis of Mono-olefinic Insect Sex Pheromones of Z- or E-Configuration
Fiandanese, Vito,Marchese, Giuseppe,Naso, Francesco,Ronzini, Ludovico
, p. 1115 - 1120 (2007/10/02)
A series of insect sex pheromones and structually related olefins have been synthesized with high stereoisomeric purity by two sequential cross-coupling reactions.Starting with (Z)- or (E)-1-bromo-2-phenylthioethene, (1) and (2), and Grignard reagents in the presence of nickel or palladium catalysts, two types of compounds have been prepared: (i) 1,2-dialkylethenes and (ii) alkenyl acetates.In the synthesis of Z-isomers, the first step involves a cross-coupling reaction of compound (1) with the appropriate Grignard reagent in the presence of a catalytic amount of .The second cross-coupling reaction is performed on the intermediate (Z)-phenylthioalkenes using a different Grignard reagent in the presence of (dppe=Ph2PCH2CH2PPh2) as a catalyst.In the synthesis of E-isomers both steps are cross-coupling reactions of Grignard reagents in the presence of as a catalyst, the first step involving compound (2) and the second step involving the intermediate (E)-phenylthioalkenes obtained.The Grignard reagents used in the synthesis of the alkenyl acetates derive from protected ω-halohydrins.
A NEW STEREOSELECTIVE SYNTHESIS OF (Z)-9-TRICOSENE, THE SEX ATTRACTANT OF THE COMMON HOUSEFLY
Moiseenkov, Alexander M.,Schaub, Bruno,Margot, Christian,Schlosser, Manfred
, p. 305 - 306 (2007/10/02)
"Muscalure" (9-tricosene) was prepared very readily by an instant-ylid reaction in a highly cis-selective manner although it was found difficult to assess the (Z/E)-ratio with accuracy.
REGIOSELECTION IN THE ALKYLATION OF TRIMETHYLSILYLALLYL ANION- STEREOSELECTIVE SYNTHESIS OF DISUBSTITUTED ALKENES.
Koumaglo, K.,Chan, T. H.
, p. 717 - 720 (2007/10/02)
The regioselection in the alkylation of trimethylsilylallyl anion can be controlled by the use of Schlosser's base to give predominately γ-product with trans geometry at the double bond.Application of this approach to the synthesis of Z-9-tricosene and the Gypsy month sex pheromone is demonstrated.
Process for the preparation of higher alkenes
-
, (2008/06/13)
A process for the preparation of a straight-chain or branched alkene which has 20 to 24 carbon atoms and in which the ethylenic bond is located after a carbon atom numbered between 8 and 11, which process comprises reacting, in an anhydrous solvent, preferably in an oxahydrocarbon an organometallic copper compound with an alkyl or alkenylsulfonate.