59128-94-8

Upstream product

• 72967-11-4 (3-methoxycarbonyl-2-propenyl)triphenylphosphonium bromide 
• 112-13-0 n-decanoyl chloride 
• 87131-20-2 (Z)-6-Bromo-tetradec-2-en-4-ynoic acid methyl ester 
• 87131-19-9 (E)-6-Bromo-tetradec-2-en-4-ynoic acid methyl ester 
• 111-83-1 1-bromo-octane 
• 87131-18-8 bromo-4 dodecyne-2 al-1 
• 29343-40-6 (+/-)-4-hydroxydodec-2-ynal diethyl acetal 
• 34656-73-0 4-tetrahydropyran-2-yloxy-dodec-2-yn-1-ol 
• 70095-33-9 (S)-3-hydroxy-1-undecyne 
• 188349-79-3 (S)-1-trimethylsilyl-1-undecyn-3-ol 
• 455331-89-2 (S)-3-(methylsulfonyloxy)-1-undecyne 
• 65866-00-4 (E)-3-methoxycarbonyl-2-propenylidenetriphenylphosphorane 
• 65451-09-4 (R)-methyl 4,5-tetradecadienoate 
• 96633-22-6 trimethylphosphonoacetate anion 

Relevant academic research and scientific papers

CHIRAL EPOXIDES AS PRECURSORS OF CHIRAL ALLENES

We have applied the Sharpless asymmetric epoxidation to allylic alcohols containing a conjugated alkyne.Reaction of dialkyl metallic cuprates with the resulting alkynyl epoxyalcohols gives dihydroxy allenes of high chiral purity.The stereochemistry of the reaction was shown to be exclusively anti when sulfide is present.

Pheromone synthesis. Part 257: Synthesis of methyl (2E,4Z,7Z)-2,4,7-decatrienoate and methyl (E)-2,4,5-tetradecatrienoate, the pheromone components of the male dried bean beetle, Acanthoscelides obtectus (Say)

Tandem Dess-Martin oxidation/Wittig reaction of (2Z,5Z)-2,5-octadien-1-ol yielded methyl (2E,4Z,7Z)-2,4,7-decatrienoate, a newly discovered pheromone component of the male dried bean beetle, while that of (±)-2,3-dodecadien-1-ol gave (±)-methyl (E)-2,4,5-tetradecatrienoate, the racemate of the known and major pheromone component. Methyl (2E,4E,7Z)-2,4,7-decatrienoate was also synthesized, which is the methyl ester of an acid metabolite of a green alga. Reduction of 2,5-octadiyn-1-ol with Zn-Cu/EtOH cleanly gave (2Z,5Z)-2,5-octadien-1-ol.

Enantioselective synthesis of allenylenol silyl ethers via chiral lithium amide mediated reduction of ynenoyl silanes and their Diels-Alder reactions

An enantioselective Meerwein-Ponndorf-Verley-type reduction of ynenoylsilanes by a chiral lithium amide followed by a Brook rearrangement and anti-mode protonation across conjugated 1,3-enynes provides allene derivatives bearing a 2-siloxyvinyl moiety in high enantioselectivity. The E/Z geometry of enol silyl ethers is controlled by the geometry of the starting enyne moiety. Thus, (E)- and (Z)-enol silyl ethers are obtained from (Z)- and (E)-ynenoylsilans, respectively. The 2-siloxyvinylallene products can participate in Diels-Alder reactions with reactive dienophiles such as PTAD, which can be achieved in a one-pot operation from ynenoylsilanes.

Pheromone synthesis. Part 249: Syntheses of methyl (R,E)-2,4,5- tetradecatrienoate and methyl (2E,4Z)-2,4-decadienoate, the pheromone components of the male dried bean beetle, Acanthoscelides obtectus (Say)

The enantiomers of methyl (E)-2,4,5-tetradecatrienoate (1), a component of the male pheromone of Acanthoscelides obtectus, were synthesized from the enantiomers of 1-undecyn-3-ol (6), which were obtained via asymmetric acetylation of (±)-1-trimethylsilyl-1-undecyn-3-ol (4) with vinyl acetate as catalyzed by lipase PS (Amano). The ortho ester Claisen rearrangement of 6 with triethyl orthoacetate was the key-step to generate the chiral allenic system. A new synthesis of (±)-1 was also executed starting from (±)-6. Three different syntheses of methyl (2E,4Z)-2,4-decadienoate (2), another component of the male pheromone of A. obtectus, were achieved by means of either palladium-catalyzed Heck reaction or a Claisen and an Al 2O3 catalyzed thermal rearrangements.

An 1,2-Elimination Approach to the Enantioselective Synthesis of 1,3-Disubstituted Linear Allenes

The construction of 1,3-disubstituted allene skeleton, which is present in many natural allenes, via an i-PrMgBr-mediated elimination of optically active 3-acetoxy-2-iodo-prop-1-ene derviatives is exemplified through the enantioselective total synthesis o

A new route to methyl (R,E)-(-)-tetradeca-2,4,5-trienoate (pheromone of Acanthoscelides obtectus) utilizing a palladium-catalyzed asymmetric allene formation reaction

A formal total synthesis of the sex attractant of male dried bean beetle, methyl (R,E)-(-)-tetradeca-2,4,5-trienoate, was achieved by a new efficient route utilizing the Pd-catalyzed asymmetric allene synthesis reaction. It was found that the atropisomeric biaryl bisphosphine (R)-segphos showed better enantioselectivity than (R)-binap in the Pd-catalyzed reaction for preparing alkyl-substituted axially chiral allenes.

A new method for synthesis of allenes, including an optically active form, from aldehydes and alkenyl aryl sulfoxides by sulfoxide-metal exchange as the key reaction and an application to a total synthesis of male bean weevil sex attractant

The sulfoxide-metal exchange reaction of β-acetoxy sulfoxides or β-mesyloxy sulfoxides, which were derived from alkenyl aryl sulfoxides and aldehydes in two steps, with a Grignard reagent or alkyllithium at low temperature gave allenes in good yields. Optically active allenes were synthesized starting from optically active 2-substituted ethenyl p-tolyl sulfoxides. A synthesis of (-)-methyl (E)-2,4,5-tetradecatrienoate, a male bean weevil sex attractant, was realized by this method.

Amplification of chirality by transition metal coordination: Synthesis of chiral allenes and allene manganese complexes of high enantiomeric purity. Synthesis of methyl (R,E)-(-)-(2,4,5-tetradecatrienoate (pheromone of Acanthoscelides obtectus (say))

The enhancement of the asymmetry of choreal oiliness by coordination with a transition metal can be turned to account for (easy) resolution of the complexes and therefore the oiliness themselves. This is illustrated here on allene aldehyde complexes of (η

LOW-MOLECULAR-MASS BIOREGULATORS. II. SYNTHESIS OF METHYL (+/-)-TETRADECA-2E,4,5-TRIENOATE-THE SEX PHEROMONE OF Acanthoscelides obtectus

A preparative method has been developed for obtaining methyl (+/-)-tetradeca-2E,4,5-trienoate - the racemate of the sex pheromone of the dried-bean beetle.Using methyl 4-chlorotetradec-5-ynoate as an example, a detailed study has been made of the dependence of the regiochemistry of reduction on the activity of a zinc-copper couple, the methods of its activation, and the acidity of the proton donor.

STEREOSELECTIVE PREPARATION OF CONJUGATED DIENOATES AND DIENAMIDES. NEW SYNTHESIS OF PELLITORINE AND PIPERCIDE

(E) and (E,E)-conjugated dienoates and dienamides of high stereoisomeric purities are prepared via thermal SO2 extrusion from cis-2,5-disubstituted-2,5-dihydrothiofene-1,1-dioxides generated by a retro Diels-Alder reaction.Applications of this method to the syntheses of two insecticidal natural dienamides : pellitorine and pipercide and of methyl tetradeca-2E,4,5-trienoate, an insect sex pheromone, are described.