10-Undecenoic acid in the synthesis of insect pheromones

The literature on the use of 10-undecenoic acid in the synthesis of insect pheromones is reviewed.Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, 450054, Ufa, prospekt Oktyabrya 71, fax (3472) 35 60 66. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 87–96, March–April, 2000.     

Ti-catalyzed cross-cyclomagnesiation of 1,2-dienes in the stereoselective synthesis of insect pheromones

The Ti-catalyzed intermolecular cross-cyclomagnesiation reaction of aliphatic and oxygenated 1,2-dienes with Grignard reagents was used as the key step to develop facile stereoselective methods for preparation of the major components of citrus leafminer moth (Phyllocnistis citrella) pheromones as well as cotton pink bollworm (Pectinophora gossypiella) and fruit fly (Drosophila melanogaster) attractants.     

昆虫性信息素的固相合成

本综述阐明昆虫性信息素固相合成的最新成就。C.C.Leznoff 开创了昆虫性信息素的固相合成,并合成了一系列信息素。他以二醇为原料,以聚合物三苯甲基氯为保护剂。陈德恒等将保护剂改成聚合物三苯甲基氯硅烷,产率比前人有所提高。陈家威等大大改进了前两人的线路,简化了步骤,只抓住关键的一步进行固相合成,总产率比前人提高得更多。     

General methodology for the synthesis of conjugated dienic insect sex pheromones

A general methodology for the synthesis of various types of dienic insect sex pheromones (Z-E, E-Z, Z-Z) is based on the carbocupration of acetylene by functionalised or non-functionalised lithium dialkyl cuprates, followed by the coupling of the resulting Z dialkenyl cuprates with functionalised or non-functionalised E or Z alkenyl iodides under Pd° catalysis. The following compounds were efficiently synthesized with a high degree of stereoisomeric purity: (E-Z)7, 9-dodecadien,-l-yl acetate 1 (Lobesia botrana), (E-Z)10, 12-hexadecadien,-l-ol 2 (Bombyx mori), (Z-E)9, 11-tetradecadien,-l-yl acetate 3Spodoptera littoralis), (Z-E)5, 7-dodecadien-l-ol 4 (Malascoma disstria), (Z-Z)11, 13-Hexadecadien-l-al 5 (Amyelois transitella), (Z)9,ll-dodecadien-l-yl acetate 6 (Diparopsis castanea) and (Z-Z)9,11-tridecadien-l-yl acetate 22 (a known “pseudo-pheromone”).     

聚合物支持的三苯基氯硅烷在昆虫性信息素固相合成中的应用

1%二乙烯基苯交联的聚苯乙烯树脂在N,N,N',N'-四甲基乙二胺的存在下用丁基锂进行锂化后与二苯基二氯硅烷反应制得聚苯乙烯支持的三苯基氯硅烷(2).这种聚合物用于一些鳞翅目(lepidoptera)昆虫的性信息素的固相合成.2与1,9-壬二醇,1,10-癸二醇和1,12-十二碳二醇反应分别生成聚合物支持的二醇单硅醚(4a,4b,4c),游离的醇基用Swern试剂(DMSO和草酸酰氯)氧化成聚合物支持的醛(5a,5b,5c),经Wittig缩合反应和用氟离子裂解后分别得到9-十四碳烯醇-1(8a),10-十四碳烯醇-1(8b)和12-十四碳烯醇-1(8c).化合物8经乙酰化后分别得到9-十四碳烯醇-1乙酸酯(9a),其顺式异构体是秋灰夜蛾(S.frugiperda,Smith)的性信息素;10-十四碳烯醇-1乙酸酯(9b),其顺式异构体是橡卷叶蛾(A.semiferamus,Walker)的性信息素;和12-十四碳烯醇-1乙酸酯(9C).9C与四氯化碲反应,硫化钠还原后转化成E-和Z-异构体比例为54:46的亚洲玉米螟(Ostriniafurnicalis)的性信息素.     

A mass-spectrometric study of insect pheromones. II. Epoxy compounds

The mass spectra of epoxy compounds have been studied and the positions of the epoxy rings and their configurations have been shown.V. I. Lenin Tashkent State University. A. S. Sadykov Institute of Bioorganic Chemistry, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 130–135, January–February, 1992.     

Simple synthesis of acetogenin transoid insect pheromones starting from acetylcyclopropane

A highly effective synthesis of a series of alkyl and 1-alkenyl cyclopropyl ketones, which are key components in the complete synthesis of a large number of transoid lepidoptera pheromones, has been developed, based on the alkylation of N-cyclohexyl-1-cyclopropylethylideneimine or its condensation with aldehydes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1555–1562, July, 1991.     

Cyclopropane intermediates in the synthesis of chiral alcohols with methyl-branched carbon skeleton. Application in the synthesis of insect pheromones

Several chiral building blocks, (2R)-2-methylundec-10-en-1-ol, (3R)-3-methylheptan-1-ol, and (4R)-4-methyloctan-1-ol, have been synthesized using cyclopropane intermediate products. It has been shown that the obtained chiral alcohols can be used in the synthesis of insect pheromones.     

Furanyl spiroketals as stereochemical relays in the synthesis of 1,9-anti diols: synthesis of insect pheromones

A suite of spiroketal insect pheromones (15 and 17a-d) has been synthesised in good yield and with very high levels of diastereoselectivity via furanyl spiroketals. Remote asymmetric induction is achieved under thermodynamic control. The use of furanyl spiroketals as temporary scaffolds in the synthesis of 1,9-anti diols has been demonstrated with the synthesis of the swede midge pheromone (2S,10S)-2,10-diacetoxyundecane 1. The enzymatic resolution of a C₂ symmetric 1,9-anti diol was used as a confirmation of diastereomeric purity.     

Metastable-ion mass spectra of insect pheromones

The laws of the fragmentation of the metastable molecular and key fragmentary ions of mono- and dienic alcohols, acetates, aldehydes, hydrocarbons, and epoxy compounds forming components of the pheromones of the turnip, tomato, and bollworm moths and other pests of agricultural crops are discussed, and the use of the laws found in the identification of compounds of this class has been demonstrated.     

Metastable-ion mass spectra of insect pheromones

The laws of the fragmentation of the metastable molecular and key fragmentary ions of mono- and dienic alcohols, acetates, aldehydes, hydrocarbons, and epoxy compounds forming components of the pheromones of the turnip, tomato, and bollworm moths and other pests of agricultural crops are discussed, and the use of the laws found in the identification of compounds of this class has been demonstrated.Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, FAX 62 70 71. Tashkent State University, FAX 46 24 72. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 455–470, July–August, 1994.     

Linear encoding of functional groups in the synthesis of heterocyclic compounds: cycloaddition of enyne and alkyne units

A family of novel [4 + 2] cycloaddition reactions is discussed for the efficient preparation of poly-substituted heterocyclic compounds in a single step starting with linear precursors. The high selectivity of the intramolecular transformation and the predefined position of the substituents in the product were governed by linear encoding in the structure of the starting reagents. The designed reactions utilized the green chemistry potential of the cycloaddition approach and provided a convenient synthetic route to cyclopentapyridines, indoles, isoindoles, indolizines, isophosphindoles, benzofurans, benzothiophenes, and benzoselenophenes (and corresponding dihydro derivatives).     

Synthesis of eight-membered ring compounds using enyne metathesis

[reaction: see text] A novel procedure for synthesizing eight-membered ring compounds was developed using ruthenium-catalyzed enyne metathesis. When a CH2Cl2 solution of enyne connected with catechol, o-amino phenol, or o-phenylenediamine was stirred in the presence of benzylidene ruthenium carbene complex (10 mol %) at room temperature overnight, an eight-membered ring compound was obtained in high yield. In a similar manner, monocyclic 1,4-diaza- or 1-oxa-4-azacyclooctene derivative was obtained in high yield.     

A general method for the synthesis of nonracemic trans-epoxides: concise syntheses of trans-epoxide-containing insect sex pheromones

A general method for the synthesis of chiral nonracemic trans-epoxides has been developed that provides rapid access to alkyl-, alkenyl-, alkynyl-, and phenyl-substituted trans-epoxides from aldehydes. This methodology has also been applied in concise and high-yielding syntheses of both trans-epoxide containing insect sex pheromones.     

Simple stereospecific synthesis of the insect sex pheromones of cossus cossus,eupoecilia ambiguella and orgyia pseudotsugata

Insect sex Pheromones $\text{6}$, $\text{7}$ and $\text{15}$ are prepared in high yield with a very high degree of Z purity (>99.9 %) by alkylation of Z dialkenyl cuprates.     

A new approach to the synthesis of racemic analogs of 1,5-dimethyl-branched insect pheromones from 4-methyltetrahydropyran

A new procedure was developed for the synthesis of racemic analogs of 1,5-dimethyl-branched insect pheromones based on monoalkylation of ethyl acetoacetate with 1-acetoxy-5-bromo-3-methylpentane produced upon decyclization of 4-methyltetrahydropyran.     

Novel liquid crystalline compounds having an enyne unit

Novel series of liquid crystalline compounds having an enyne unit, 1-(4-alkylphenyl)-4-(trans-4-alkylcyclohexyl)-but-3-en-1-yne and 1-(4-alkoxyphenyl)-4-(trans-4-alkylcyclohexyl)-but-3-en-1-yne are presented. The synthetic methods, mesomorphic phases, and some physical properties of these series are reported.     

Selective tandem enyne metathesis for the synthesis of functionalized cycloheptadienes

The regio- and site-selective ring expansion of dienes and the regioselective ring expansion of substituted cyclopentenes provide 1,3-cycloheptadienes by enyne metathesis under methylene-free conditions. Site-selectivity results from differential ring strain among two different cycloalkenes in diene reactants. The high regioselectivity found in the ring expansion of tetrahydroindene (THI) is explained on the basis of a selective ring opening by the second generation Grubbs' ruthenium carbene complex. The ring opening of substituted cyclopentenes and cyclopentene contained in a bicyclic ring system was also achieved. The ring expansion of bicyclic dienes provided seven-membered dienes contained in the bicyclo[5.2.0]nonane ring system. Details of the structural analysis are also discussed. A mechanistic analysis is provided to account for the data presented herein.