58761-29-8

Upstream product

• 3391-86-4 1-octen-3-ol 
• 141-97-9 ethyl acetoacetate 
• 109-72-8 n-butyllithium 
• 20036-40-2 1-(2-vinyl-cyclopropyl)-ethanone 
• 68883-76-1 (E)-1-chlorooct-2-ene 
• 150942-98-6 t-butyl lithioacetate 
• 106051-45-0 (5E)-undeca-1,5-diene 
• 133967-70-1 (Z)-2-(methylthio)-1,5-undecadiene 
• 628-71-7 1-Heptyne 
• 78-94-4 methyl vinyl ketone 
• 53268-67-0 (E)-1-chloro-hept-1-ene 
• 53434-74-5 (E)-1-bromohept-1-ene 
• 60595-37-1 (E)-1-iodohept-1-ene 
• 144462-99-7 (E)-undec-5-en-2-ol 

Relevant academic research and scientific papers

Ruthenium-Catalyzed Oxidative Cross-Coupling Reaction of Activated Olefins with Vinyl Boronates for the Synthesis of (E, E)-1,3-Dienes

An oxidative cross-coupling reaction between activated olefins and vinyl boronate derivatives has been developed for the highly stereoselective construction of synthetically useful (E,E)-1,3-dienes. The highlight of this reaction is that exclusive stereoselectivity (only E,E-isomer) was achieved from a base-free, ligand-free, and mild catalytic condition with a less expensive [RuCl2(p-cymene)]2 catalyst.

Mechanistic dichotomy in CpRu(CH3CN)3PF6 catalyzed enyne cycloisomerizations

Enynes are easily accessible building blocks as a result of the rich chemistry of alkynes and thus represent attractive substrates for ring formation, A ruthenium catalyst for cycloisomerization effects such reaction of 1,6- and 1,7-enynes typically at room temperature in acetone or DMF under neutral conditions. The reaction is effective for forming five- and six-membered rings of widely divergent structure. The alkyne may bear both election-donating and election-withdrawing substituents. The alkene may be di- or trisubstituted. Introduction of a quaternary center at the propargylic position of an ynoate, however, completely changes the nature of the reaction. In the case of a 1,6-enynoate, a seven-membered ring forms in excellent yield under equally mild conditions. Evidence is presented to indicate a complete change in mechanism. In the former case, the reaction involves the intermediacy of a ruthenacyclopentene. In the latter case, a C-H insertion to form a π-allylruthenium intermediate is proposed and supported by deuterium-labeling studies. A rationale is presented for the structural dependence of the mechanism.

Nickel-catalyzed electrochemical couplings of vinyl halides: Synthetic and stereochemical aspects

Homo- and cross-coupling involving alkenyl halides have been performed efficiently using an electroassisted nickel-complex catalysis. Valuable product such as conjugated dienes, β,γ- or γ,δunsaturated esters, ketones, or nitriles, as well as alkenylated aryl compounds are thus prepared with high yields and high stereoselectivity. Partial isomerization is only observed in a few cases, when the alkenyl halide is involved in a late step of the catalytic cycle. This is the case in the preparation of (Z,Z)-1,3-diene.

Stereoselective alkenylation of activated olefins via nickel-catalyzed electroreductive coupling

The nickel-catalyzed electroreductive conjugate addition of (Z)- or (E)-alkyl halides to electron-deficient olefins in the presence of a sacrificial iron rod as the anode proceeds with complete retention of the stereochemistry of the alkenyl part and affo

SYNTHESIS WITH MANGANIC SALTS; PART III: SYNTHESIS OF 1,4-DIKETONES THROUGH MANGANIC ACETATE-MEDIATED ADDITION OF KETONE TO ISOPENTENYL SULFONES. ACETOXYLATION OF Β,Γ-UNSATURATED KETONES BY MANGANOUS AND CUPRIC ACETATES

Conditions have been found to selectively add ketones to isopentenyl sulfones.The major product, a ketone bearing a methylene group at the γ position, gave upon ozonolysis the corresponding 1,4-diketone.The usefulness of the overall process was illustrated by the efficient syntheses of jasmone and of one half of pyrenophorine.The γ-acetoxy conjugated enones that invariably formed during these additions resulted from the oxidation of an isomeric β,γ-unsaturated ketone by manganous and cupric acetates.Such an acetoxylation has been used to prepare 6β-acetoxy-cholestenone from cholesterol and also to prepare chrysanthemic acid.

DIASTEREOSELECTIVE SYNTHESIS OF (E)-ALKENES AND (E)-1,ω-DIENES STARTING FROM DIASTEREOISOMERIC MIXTURES OF l-BROMO-l-ALKENES : NEW SYNTHESES OF MONOUNSATURATED OR BRIDGED RING-KETAL NATURALLY OCCURRING SUBSTANCES.

The PdCl2(dppf)-catalyzed cross-coupling reaction between diastereoisomeric mixtures of l-bromo-l-alkenes which contain n equiv. of (E)-stereoiomers and n equiv. of Grignard reagents allows to obtain (E)-alkenes or (E)-l,ω-dienes having 95.5-99percent stereoisomeric purity in satisfactory yields.Such compounds are useful precursors to several naturally occurring substances.

A Stereospecific Synthesis of (Z)-δ-Halo-γ,δ-unsaturated Ketones via Haloboration Reaction of Terminal Alkynes

Michael-type reactions of (Z)-β-bromo- and iodoalkenyl-9-borabicyclononanes (5), readily available by haloboration of 1-alkynes, with acyclic α,β-unsaturated ketones (2) in a nonpolar solvent under Lewis acidic conditions are presented.The products, (Z)-δ-halo-γ,δ-unsaturated ketones (6), are obtained in stereochemically pure form (>98 percent).Since the haloalkenylboranes (5) are prepared in situ from haloboranes (4) and 1-alkynes, the present reaction provides a stereospecific, one-pot, and general synthesis of the title compounds (6).When methyl vinyl ketone (MVK) is used as the Michael acceptor, aldol condensation of the intermediate boron enolate with an excess of MVK occurs.However, the aldol (7) is transformed into the parent haloenone (6') without difficulty upon subsequent, in situ treatment with a base.The same product (6') is prepared directly by the reaction with 3-(trimethylsilyl)-3-buten-2-one.Synthetic utility of the present method is demonstrated by selective syntheses of several natural products.Sulcatol (11) is obtained in an overall yield of 63 percent starting from propyne.In a similar manner, trans-geranyl acetone (14) and trans-nerolidol (15) are prepared stereospecifically (>98 percent) in 62 and 72 percent yields, respectively, from 6-methyl-5-hepten-1-yne (12).

Chain extension with tert-butyl lithioacetate

Iodides containing methylene-interrupted triple or double bonds can be chain-extended in 45-73percent yield by reaction with tert-butyl lithioacetate in THF/HMPT at -35 deg C and subsequent acid-catalyzed thermolysis at 100 deg C.Alkyl and allyl bromides or iodides give acids in yields of 60 to 89percent.In some cases, minor amounts of methyl ketones were found.Alkyl chlorides and alkyl methane-, benzene- or p-toluenesulphonates are not suitable.