Synthesis of 7E,9Z-dodecadienyl acetate,the sex pheromone ofLobesia botrana Shiff

Two syntheses of 7E,9Z-dodecadienyl acetate from 1,3-butadiyne were carried out using either 2E,4Z-heptadienyl acetate or 1-bromo-3E,5Z-octadiene as the key intermediates. The latter underwent organocopper cross-coupling with the respective complementary Grignard reagents (prepared from the corresponding 1-tert-butoxy--chlorohydrins) as alkylating agents.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 766–768, April, 1993.     

Synthesis from 10-undecenoic acid of octadeca-2E,13Z-dienylacetate, a component of the sex pheromones ofSynanthedon tipuliformis andZenzera pyrina

A new synthesis of octadeca-2E,13Z-dienylacetate from 10-undecenoic acid is developed by constructing the carbon framework of the pheromone in the key step and introducing the 2E double bond by Doebner condensation of hexadec-11-ynal and malonic acid.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. 164–166, March–April, 2000.     

A simple synthesis of 4E,7Z-tridecadien-1-yl acetate,a component of the sex pheromone of the potato mothPhtorimaea operculella (Lepidoptera:Gelehiidae)

A simple, five-step synthesis of the title compound was developed starting from commercially available 2,4-nonadienal. The overall yield of the pheromone is 29%, and the geometric purity of the ⁴ and ⁷ double bonds is 95%. TheZ configuration of the ⁷ bond results from the 1,4-cis-hydrogenation of the intermediate 1,4,6-undecatrien-3-ol in the presence of an (arene)chromium tricarbonyl complex, while theE configuration of the ⁴ bond arises in the Claisen-Johnson rearrangement occuring in the reaction of 1,5Z-undecadien-3-ol with trimethyl orthoacetate.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2350–2353, September, 1996.     

Synthesis of (Z/E)-11-tetradecen-1-ol, a component of Ostrinia nubilalis sex pheromone

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.     

Synthesis of (7Z,9Z)-dodecadienyi acetate,a component of sex pheromones of the leafrollersEpinotia andEucosma,using conjugated diynols

Two analogous routes to the title pheromones were elaborated based on organocuprate cross-coupling ofZ,Z-dienic electrophiles, (2Z,4Z)-1-acetoxy-2,4-heptadiene (6) and (3Z,5Z)-1-bromoctadiene (8), with -tert-butoxy-1-chloropentane and -butane, respectively. Optimal conditions for the reduction of 2,4-heptadiyn-1-ol and 3,5-octadiyn-1-ol to the respectiveZ,Z-alkadienols as precursors for the electrophiles were found. Treatment of diynols with activated zinc in aqueous alcohol provided high geometrical purity of the product (94 %). In both cases, copper-catalyzed cross-coupling afforded 1-tert-butoxy-7,9-dodecadiene (four stereoisomers), acetolysis of which gave the target pheromone contaminated by stereoisomers. In the case of allylic electrophile6, the reaction occurred with the loss of the initial configurational purity, whereas the use of homoallylic bromide8 ensured almost complete retention of the configuration of the double bonds and obtaining the target pheromone of 87 % configurational purity.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1656–1660, September, 1993.     

An alternative synthesis of a sex pheromone of the dry bean beetleCallosobruchus analis

A formal total synthesis of 3-methylhept-2(Z)-enoic acid, a sex pheromone of the dry bean beetleCallosobruchus analis, was performed on the basis of a highly stereoselective version of the Peterson olefination of ketones developed previously by the authors. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1389–1392, July, 1999.     

Stereospecific synthesis of 11E-tetradecenal, 11E-tetradecen-1-ol, and its acetate, pheromone components of insects ofLepidoptera order, from 10-undecenoic acid

A regio- and stereospecific synthesis of 11E-tetradecen-1-ol and its derivatives, which are pheromone components of many insect species ofLepidoptera order, by means of a reaction of methylmagnesium cuprate reagent with 1,12-tridecadien-3-yl acetate by theS _N2′ mechanism, was carried out. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1074–1075, May, 1997.     

New synthesis of serricornin,the sex pheromone of the cigarette beetle (Lasioderma serricorne)

A new approach to the total synthesis of serricornin, the sex pheromone of the cigarette beetle, based on readily available (4S,5E)-4-methyhept-5-enenitrile was implemented.     

Effective synthesis of femrrulactone II based on the use of 2-carhoxyethyltriphenylphosphonium bromide

A simple synthesis ofS,3Z-dodecen-11-olide, a component of the aggregation pheromone of the rusty grain beetleCryptolestes ferrugineus (Stephen), was developed. The key stage was Wittig olefination of C₉-aldehyde, prepared fromS-propylene oxide, with C₃-phosphorane generated from the title phosphonium salt.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 791–794, April, 1993.The authors are grateful to G.A.Zakladnoi and N.S.Akhaev for performing the bioassay of ferrulactone II.     

Highly stereoselective synthesis of a sex pheromone of the dry bean beetleCallosobruchus analis

Total synthesis of 3-methylhept-2(Z)-enoic acid, a sex pheromone of the dry bean beetleCallosobruchus analis, has been performed using a previously developed highly stereoselective method of the construction of disubstituted (Z)-methylolefins based on the higher thermodynamic stability of (E)-isomers of α,β-disubstituted acroleins. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1385–1388, July, 1999.     

The (E)/(Z)-ratio in the reaction of 5-(2-aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidines with bromine

Summary 3-Aryl-, 3-benzyl-, and 3H-5-(2-aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidines3a–h react with bromine in acetic acid solution to give mixtures of the respective 5-aroylmethylene (E) and (Z) diastereomeric derivatives5 and6. They contain more than 85% of the (E)-diastereomers along with some pure isomers. The intermediacy of the 5-bromo derivatives4 is proven and a plausible route of the reaction is presented. Structures of compounds3–6 are evidenced by analytical and spectral data.

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Das Verhältnis von (E)- und (Z)-Isomeren bei der Reaktion von 5-(2-Aryl-2-oxomethyl)-2-thioxo-4-oxo-1,3-thiazolidinen mit Brom

Zusammenfassung 3-Aryl-, 3-Benzyl- und 3H-5-(2-Aryl-2-oxoethyl)-2-thioxo-4-oxo-1,3-thiazolidine3a–h reagieren mit Brom in essigsaurer Lösung zu Gemischen der entsprechenden diastereomeren 5-Arylmethylen-Derivate ((E) und (Z))5 und6. Sie enthalten mehr als 85% des (E)-Diastereomeren. Die intermediäre Natur der 5-Brom-Derivate4 wird bewiesen; ein Reaktionsweg wird vorgeschlagen. Die Strukturen der Verbindungen3–6 werden durch analytische und spektroskopische Daten abgesichert.

     

Stereospecific synthesis of the sex pheromone of the passionvine mealybug, Planococcus minor

A short and completely stereospecific synthesis of (E)-2-isopropyl-5-methyl-2,4-hexadienyl acetate, the very recently identified sex pheromone of the passionvine mealybug Planococcus minor, is described. In the key step, CuI-catalyzed anti-addition of a Grignard reagent to a propargyllic alcohol intermediate gave the required trisubstituted alkene with 100% regio- and stereospecificity. The stereochemical purity of the pheromone is critically important because the (Z)-isomer is a powerful behavioral antagonist.     

Cyclization of ortho-(alk-2-enyl)anilines under the action of iodine

The reaction of ortho-(cyclohex-2-enyl)aniline with I₂ in nonpolar and polar solvents affords predominantly 1-iodohexahydrocarbazole and azatricyclotridecatriene, respectively. Under analogous conditions, 4-methyl-2-(1-methylbut-2-en-1-yl)aniline undergoes cyclization to form exclusively products with quinoline structures regardless of the solvent used.     

Reactions of cis-2-Boryl-1-stannylalkenes with Carbodiimides, Thiocyanates, Isothiocyanates, and Isocyanates

The reactions of (E)-2-diethylboryl-1-trimethylstannylbut-1-ene and (Z)-3-diethylboryl-2-trimethylstannylpent-2-ene with carbodiimides, methyl thiocyanate, thioisocyanates, and isocyanates were studied, and the products were characterized by multinuclear magnetic resonance spectroscopy (¹H, ¹¹B, ¹³C and ¹¹⁹Sn NMR). It was found that carbodiimides bearing tert-butyl or trimethylsilyl groups at the nitrogen atoms do not react with (E)-2-boryl-1-stannylalkenes, in contrast to dicyclohexylcarbodiimide. There was also no reaction in the case of MeSCN. All other reactions proceed via a weak NB adduct formation in the initial step, followed by different rearrangements, depending on the structure of reagents as well as on the substitution pattern at the C=C bond in alkenes. New heterocycles are formed, in which the boron atom is either tricoordinated (1,2-azaborolenes, 1,2-azaborolan! es), a nd one ethyl group has been transferred to the neighbor olefinic carbon atom, or the boron atom is tetracoordinated (1,2-azaboratoles, 1,2-oxoniaboratoles), and the trimethylstannyl group has migrated to one of the heteroatoms of the heterocumulenes.     

A novel polyfunctional chiral building block derived from (S)-ethyl lactate. Application to the synthesis of the sex pheromone of the southern corn rootworm (Diabrotica undecimpunctata howardi)

Highly enantiomerically pure (4S, 5E)-4-bromomethylhept-5-enenitrile was prepared from (S)-ethyl lactate by a six-step procedure involving a rearrangement of chiral cyclopropylcarbinol. This product was used for the synthesis of the sex pheromone of the southern corn rootworm (Diabrotica undecimpunctata howardi), (10R)-10-methyltridecan-2-one. For preliminary communication, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 151–155, January, 2000.     

Intramolecular cyclization ofortho-(cyclohex-2-enyl)anilines. Modified synthesis of ellipticine

It was found that the reactions of arylamines with 3-bromocyclohexene afforded hydrocarbazole compounds in 64–78% yields. A modified procedure for the synthesis of antitumor alkaloid ellipticine was proposed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2144–2149, November, 1999.     

Synthesis of 4<Emphasis Type="Italic">E</Emphasis>,7<Emphasis Type="Italic">Z</Emphasis>-tridecadien-1-ylacetate,a component of the <Emphasis Type="Italic">Phthorimaea opercucella</Emphasis> sex pheromone

A new synthetic approach to 4E,7Z-tridecadien-1-ylacetate, a component of the Phthorimaea opercucella (Zeller) potato moth sex pheromone, was developed using a highly stereoselective Claisen rearrangement and Wittig reaction. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 235–236, May–June, 2007.     

A simple synthesis of acetyl and propionyl cyclododecanes

1-Formyl-4,8-cyclododecadiene, obtained by hydroformylation of 1,5,9-cyclododecatriene, reacts with MeMgHal or EtMgHal to give 1-(l-hydroxyethyl)-or 1-(l-hydroxypropyl)-4,8-cyclododecadiene, respectively. The hydrogenation of their double bonds and subsequent oxidation of the resulting alcohols afford, in high yields, acetyl- or propionylcyclododecane, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 418–419, February, 1993.     

A novel polyfunctional chiral building block derived from (S)-ethyl lactate. Application to the synthesis of the sex pheromone of the southern corn rootworm (Diabrotica undecimpunctata howardi)

Highly enantiomerically pure (4S, 5E)-4-bromomethylhept-5-enenitrile was prepared from (S)-ethyl lactate by a six-step procedure involving a rearrangement of chiral cyclopropylcarbinol. This product was used for the synthesis of the sex pheromone of the southern corn rootworm (Diabrotica undecimpunctata howardi), (10R)-10-methyltridecan-2-one. For preliminary communication, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 151–155, January, 2000.     

Synthesis of (S)-6-methylhept-5-en-2-ol, the aggregation pheromone ofGnathotrichus sulcatus

An enantioselective (ee−50%) four-step synthesis of (S)-6-methylhept-5-en-2-ol (“sulcatol”), which is the aggregation pheromone ofGnathotrichus sulcatus, from 3S,7-dimethylocta-1,6-diene was developed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 713–717, April, 2000.