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The palladium-catalyzed arylation of enol silyl ethers, siloxydienes, silyloxycyclopropane with triarylantimony diacetates was carried out in the presence of PdCl2(CH3CN)2 (5 mol%) in DME–CH3CN at room temperature under mild conditions.

The copper-catalyzed N-arylation of amines with hypervalent iodonium compounds with secondary aliphatic amines, aromatic amines, azoles and amides was accomplished with catalytic CuI (10 mol%) or Cu(acac)2 (5 mol%) in the presence of Na2CO3 or K2CO3 as a base in CH2Cl2 or toluene under mild conditions.

The palladium-catalyzed cross-coupling reaction of iodinanes (iodonium salts and iodanes) with organoboron compounds to form carbon-carbon bonds was achieved at ambient temperature under aqueous conditions in the absence of base. Coupling of phenylboronic acid with diphenyliodonium tetrafluoroborate in the presence of Pd(PPh(3))(4) (0.2 mol %) or Pd(OAc)(2) (0.2 mol %) under aqueous conditions gave biphenyl in almost quantitative yield. Under the same conditions, substituted boronic acids, boronates, and trialkylboranes were readily coupled with diaryl-, alkenyl-, and alkynyliodonium salts. Finally, the iodanes ArI(OH)OTs underwent cross-coupling with boronic acids, boronates, and trialkylboranes to afford biphenyls and aryl-substituted alkenes.

Highly stereoselective alkylative and arylative cyclization reactions of allenyl-aldehydes and -ketones with organozinc reagents occur efficiently in the presence of catalytic Ni(COD)2 to afford cis-fused homoallylic cyclopentanols.

The palladium(0)-catalysed coupling and cyclisation of allenyl alcohols and allenyl amines with hypervalent iodonium salts afforded cyclised heterocyclic acetals and morpholines under mild conditions.

The regio- and stereoselective toluene-p-sulfonyl-mediated radical cyclization of bis(allenes) with p-TsBr and p-TsSePh was carried out in the presence of a catalytic amount of AIBN to afford the trans-fused five-membered ring containing vinyl sulfones and bromide or selenide functionalities.

[reaction: see text] The arylative cyclization of allenyl-aldehydes with aryl iodides and hexa-n-butyldistannane to form substituted cyclopentanols and cyclohexanols by tandem palladium-catalyzed carbostannylation and allylation was achieved under mild conditions.

The palladium-catalyzed arylation of enol silyl ethers, siloxydienes, silyloxycyclopropane with triarylantimony diacetates was carried out in the presence of PdCl2(CH3CN)2 (5 mol%) in DME–CH3CN at room temperature under mild conditions.

The copper- and manganese-catalyzed homocoupling of aryl-, alkenyl-, and alkynylstannanes to afford biaryls. 1,3-dienes, and 1,3-diynes were achieved in the presence of iodine at 100 °C in good yields.

The palladium- and copper-catalyzed cross-coupling of diaryl- or divinyl tellurium dichlorides with organostannanes has been achieved in the presence of PdCl2 (10 mol%) or CuI (10 mol%) with Cs2CO3 (2 equiv.) in MeCN in good to moderate yields; alternatively, the palladium- and copper-catalyzed carbonylative cross-coupling of organotellurium dichlorides with organostannanes was readily accomplished under atmospheric pressure of CO in good to moderate yields.

The copper iodide-catalyzed cross-coupling of polymer bound aryl iodide with organostannanes in N-methyl-2-pyrrolidone (NMP) was accomplished smoothly in the presence of NaCl.

The MnCl2·4H2O-catalyzed cross-coupling and carbonylative cross-coupling of organo-stannanes with hypervalent iodonium salts afforded biaryls and biaryl ketones, respectively.

The palladium-catalyzed cross-coupling of organolead triacetates with organostannanes has been accomplished in the presence of Pd2(dba)3·CHCl3 (5 mol%) and NaOMe (5 equiv.) in MeOH–MeCN (1:1) under mild conditions.

Copper(I) iodide catalyses the homocoupling of aryl-, alkenyl- and alkynyl-substituted chloro- or fluoro-dimethylsilanes under mild conditions to afford biaryls, dienes and diynes, respectively.

The nucleophilic ring opening of the cyclic carbonates of optically active threo-2,3-dihydroxy esters 1 afforded the α-substituted β-hydroxy esters 2 with highly regio- and stereo-selectivity under mild conditions. The α-sulfanyl or α-iodo β-hydroxy esters 2 thus obtained were transformed to the β-hydroxy esters 3, which are useful chiral synthons for natural product synthesis.

The acetonides, cyclic carbonates, or cyclic sulfites of γ,δ-dihydroxy (E)-α,β-unsaturated esters have been found to undergo facile reductive cleavage with samarium diiodide or magnesium in methanol to provide δ-hydroxy (E)-β,γ-unsaturated esters or δ-hydroxy esters, respectively. Using the δ-hydroxy ester 3b as a chiral synthon, (–)-5-hexadecanolide, the pheromone of the oriental hornet Vespa orientalis was synthesized.

Reaction of cyclic carbonates or sulfites of acyclic alkynyl diols with organocopper reagents proceeded in S N 2′ fashion and afforded α-allenic alcohols of high enantiomeric purity. The stereochemistry of this transformation was shown to be highly anti -diastereoselective.

The cyclic carbonates of acyclic vinyl diols react with nucleophiles in the presence of a palladium complex as a catalyst under neutral conditions to afford alkylated ( E )-allylic alcohols with highly regio-, and diastereoselectivity. This reaction represents an efficient 1,3-chirality transfer method.

Optically active (E,S)-γ-hydroxy-α,β-unsaturated sulfones and (S)-Iµ-hydroxy-(E,E)-α,γ-dienyl sulfones have been prepared in a one-pot dehydration procedure from β,γ-dihydroxy sulfones and δ,Iµ-dihydroxy allyl, sulfones, respectively, via an elimination reaction of the corresponding cyclic sulfites or carbonates formed in situ by treatment with thionyl chloride or carbonyldiimidazole.

The ligand-free Pd(OAc)2-catalysed coupling reaction of aryl-, alkenyl- and alkynyl-iodonium tetraflouroborate and iodanes with terminal alkynes proceeds readily in the presence of NaHCO2 in aqueous medium to afford the substituted alkynes in high yields under mild conditions.

The decarboxylation–hydrogenolysis of prop-2-ynylic cyclic carbonates which have an internal acetylenic bond with ammonium formate in the presence of a catalytic amount of [Pd(acac)2] and Bun3P afforded (Z)-homoallylic alcohols or homoprop-2-ynylic alcohols depending on the reaction conditions, however, hydrogenolysis of terminal prop-2-ynylic cyclic carbonates gave homoallylic alcohols; using (Z)-homoallylic alcohol 2b as a chiral synthon, the male sex pheromone of the pyralid moth Aphomia gularis has been synthesized.

(-)-(5R,6S)-6-Acetoxy-5-hexadecanolide, (-)-1, the natural mosquito oviposition attractant pheromone was synthesized from readily available carbohydrate, (-)-2-deoxy-d-ribose, using radical carbon-carbon bond formation as the key step.

(1989). A CONVENIENT ONE-STEP SYNTHESIS OF AROYL CYANIDES FROM AROMATIC ALDEHYDES. Organic Preparations and Procedures International: Vol. 21, No. 3, pp. 383-385.

1,1-Dichloro-2,3,4,5-tetraphenyl-1-silacyclopenta- 2,4-diene was synthesized through the reaction of with 1,4-dilithiotetraphenylbutadiene in 50% yield. From the reaction of this silole with metal, an air sensitive red-brownish solid was obtained. Treatment of this reaction product with gave 1,1-dimethyl-2,3,4,5-tetraphenyl-1-silacyclopenta- 2,4-diene and 1,1-bis(trimethylsilyl)-2,3,4,5-tetraphenyl-1-silacyclopenta-2,4-diene, respectively. From these results, the formation of reactive 2,3,4,5-tetraphenyl-1-silacyclopenta-2,4-dienyl dianion was confirmed.

A mixture of (Z,Z)-3,13-octadecadien-1-yl acetate(1) and its (E,Z)-isomer(2), the sex pheromone of the cherry tree borer, Synanthedon hector Butler was synthesized. (Z)-11-Octadecen-1-al(3) was prepared from 1,10-decandiol. The Wittig reaction the above aldehyde3 with carboethoxymethylenetriphenylphosphorane, or the Wadsworth-Emmons reaction of the above aldehyde3 with the anion of triethylphosphonoacetate gave ethyl (Z,Z)-2,13-octadecadienoate and its (E,Z)-isomer. Deconjugative protonation of ethyl (Z,Z)-2,13-octadecadienoate and its (E,Z)-isomer with potassium hexamethyldisilazide followed by aqueous ammonium chloride work-up afforded stereoselectiv디y ethyl (E,Z)-3,13-octadecadienoate and its (Z,Z)-isomer, respectively, of which stereoselectivity was adjusted to give the product in the required ratio. Exposure of the above deconjugated ester to excess lithium aluminium hydride resulted in formation of the penultimate (Z,Z)-3,13-octadecadien-1-ol and its (E,Z)-isomer. Acetylation of the desired alcohols afford the final products, (Z,Z)-3,13-octadecadien-1-yl acetate(1) and its (E,Z)-isomer(2).

(1989). A CONVENIENT ONE-STEP SYNTHESIS OF AROYL CYANIDES FROM AROMATIC ALDEHYDES. Organic Preparations and Procedures International: Vol. 21, No. 3, pp. 383-385.

(+)-(5S,6R)-Erythro-6-acetoxy-5-hexadecanolide, an optically active form of them ajor component of an oviposition attractant pheromone of a mosquito Culex pipiens fatigans, was synthesized enantiospecifically from (-)-2-deoxy-D-ribose.

A stereoselective synthesis of 3-phenoxybenzyl ()-cis and trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-1-cyclopropanecarboxylic acid starting from readily available 2-methyl-3-buten-2-ol() is described. Allylic rearrangement of 2-methyl-3-buten-2-ol, in the presence of acetic acid and acetic anhydride gave 3-methyl-2-butenyl acetate(). The [3,3] sigmatropic rearrangement of the allyl acetate(), as the silylketene acetal, produced the -unsaturated acid(). Treatment of 3,3-dimethyl-4-pentenoic acid() with SOCl2 followed by esterification with 3-phenoxybenzyl alcohol yielded 3, 3-dimethyl-4-pentenoic acid ester(). Addition of carbon tetrachloride to the olefin ester() furnished 4,6,6,6-tetrachloro-3,3-dimethylhexanoic acid ester (). Cyclization with potassium t-butoxide and elimination of hydrogen chloride afforded 3-phenoxybenzyl () cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-1-cyclopropanecarboxylic acid.

Stereochemical control of the Wittig reaction of the primary aldehyde, 8-acetoxyoctan-1-al (7) with the nonstabilized alkylide, triphenylphosphonium n-butylide (6), was achieved by controlling the reaction conditions including solvent, temperature and inorganic salts. These conditions can be applied to the direct sythesis of the mixture of (Z)-, and (E)-8-dodecen-1-yl acetate, the sex pheromone of the oriental fruit moth, Grapholitha molesta. The primary aldehyde, 8-acetoxyoctan-1-al (7) was synthesized from 1,8-octanediol which is cheap and readily available.

Synthesis and biological activity test are described for the (Z)-11-hexadecen-1-ol, (Z)-11-hexadecen-1-yl acetate, and (Z)-11-hexadecen-l-al, the sex pheromone of the diamond back moth, Plutella xylostella L.. Lithium acetylide was alkylated with 10-bromodecan-1-ol THP ether to give 11-hexadecyn-l-ol THP ether. 11-Hexadecyn-l-ol THP ether was stereoselectively reduced over Pd/BaSO4to yield (Z)-11-hexadecen-l-ol THP ether, which was in turn deprotected to provide (Z)-11-hexadecen-l-ol. (Z)-11-Hexadecen-l-ol was acetylated and oxidized to afford (Z)-11-hexadecen-1-yl acetate and (Z)-11-hexadecen-l-al, respectively. Biological activity test of the synthetic compounds, (Z)-11-hexadecen-l-ol, (Z)-11-hexadecen-1-yl acetate, and (Z)-11-hexadecen-l-al in the ratio of 0.1 : 5 : 5 was tested in the field using polyethylene capsules as containers. The numbers of moth trapped with pheromone vials were counted.

Synthesis and Biological activity test are described for the (E)-11-tetradecen-1-yl acetate and (Z)-11-tetradecen-1-yl acetate, the sex pheromone of the Asiatic leafroller moth (Archippus breviplicanus Walsingham). 10-Bromodecan-1-ol THP ether was prepared from 10-bromodecan-1-ol. In liquid ammonia with THF and HMPA as cosolvents, sodium acetylide could be alkylated with 10-bromodecan-1-al THP ether to give 11-dodecyn-1-ol THP ether. 11-Dodecyn-1-ol THP ether was then treated with n-Buli in THF to give the lithium acetylide, which was alkylated with bromoethane to afford 11-tetradecyn-1-ol THP ether. 11-Tetradecyn-1-ol THP ether was then reduced over and with Na in liquid to give (Z)-11-tetradecen-1-ol THP ether and (E)-11-tetradecen-1-ol THP ether, respectively. (Z)-and (E)-11-Tetradecen-1-ol THP ether thus obtained were deprotected by refluxing in the presence of PPTS and ethanol. (Z)-and (E)-11-tetradecen-1-ol were acetylated with acetic anhydride to afford the final products, (Z)-11-tetradecen-1-yl acetate (1) and (E)-11-tetradecen-1-yl acetate (2), respectively. The synthetic pheromone thus obtained was attractive to the males of the Asiatic leafroller moth in the field.

(7Z, 11E)-7, 11-Hexadecadien-1-yl acetate(1), the sex pheromone of the female Angoumois grain moth, Sitotroga cerealella, was synthesized via the acetylenic intermediate, (11E)-11-hexadecen-7-yn-ol THP ether(2). The acetylenic compound was prepared from 7-octyn-1-ol THP ether(4) and (3E)-1-bromo-3-octene(3). The (E)-homoallylic bromide 3 was synthesized by the Julia olefin synthesis of 1-cyclopropylpentan-1-ol(6).

Synthesis and biological activity test are described for the (Z)-9-tetradecen-1-yl acetate(1) and (Z)-11-tetradecen-1-yl acetate(1) and (Z)-11-tetradecen-1-yl acetate(2), the sex pheromone of the summer fruit tortrix moth, Adoxophyes orana. 8-Bromoctan-l-ol THP ether was prepared from 8-bromoctan-l-ol. The lithium anion of 1-hexyne was alkylated with 8-bromoctan-l-ol THP ether gave 9-tetradecyn-l-ol THP ether. Catalytic hydrogenation over Pd/BaSO4 followed by deprotection afforded (Z)-9-tetradecen-l-ol. Acetylation gave (Z)-9-tetradecen-1-yl acetate(1). l0-Bromodecan-l-ol THP ether was obtained from l0-bromodecan-l-ol. In liquid ammonia with THF and HMPA as cosolvents, sodium acetylide could be alkylated with 10-bromodecan-l-ol THP ether to give 11-dodecyn-l-ol THP ether. 11-Dodecyn-l-ol THP ether was then treated with n-BuLi in THF to give the lithium acetylide, which was alkylated with bromoethane to afford 11-tetradecyn-l-ol THP ether. Catalytic hydrogenation, deprotection, and acetylative gave (Z)-11-tetradecen-1-yl acetate(2). The synthetic pheromone thus obtained was attractive to the males of the summer fruit tortrix in the field.